ASTM D6110-18

Standard Test Method for Determining the Charpy Impact Resistance of Notched Specimens of Plastics

SIGNIFICANCE AND USE
5.1 Before proceeding with this test method, refer to the material specification for the material being tested. Any test specimen preparation, conditioning, dimensions and testing parameters required by the materials specification shall take precedence over those required by this test method. Table 1 of Classification D4000 lists the ASTM materials standards that currently exist. If there is no material specification, then the requirements of this test method apply.  
5.2 The pendulum impact test indicates the energy to break standard test specimens of specified size under stipulated conditions of specimen mounting, notching (stress concentration), and pendulum velocity at impact.  
5.3 For this test method, the energy lost by the pendulum during the breakage of the specimen is the sum of the energies required to initiate fracture of the specimen; to propagate the fracture across the specimen; to throw the free ends of the broken specimen (toss energy); to bend the specimen; to produce vibration in the pendulum arm; to produce vibration or horizontal movement of the machine frame or base; to overcome friction in the pendulum bearing and in the indicating mechanism, and to overcome windage (pendulum air drag); to indent or deform, plastically, the specimen at the line of impact; and to overcome the friction caused by the rubbing of the striking nose over the face of the bent specimen.
Note 5: The toss energy, or the energy used to throw the free ends of the broken specimen, is suspected to represent a very large fraction of the total energy absorbed when testing relatively dense and brittle materials. No procedure has been established for estimating the toss energy for the Charpy method.  
5.4 For tough, ductile, fiber-filled, or cloth-laminated materials, the fracture propagation energy is usually large compared to the fracture initiation energy. When testing these materials, energy losses due to fracture propagation, vibration, friction between the striking no...
SCOPE
1.1 This test method is used to determine the resistance of plastics to breakage by flexural shock as indicated by the energy extracted from standardized (see Note 1) pendulum-type hammers, mounted in standardized machines, in breaking standard specimens with one pendulum swing. This test method requires specimens to be made with a milled notch (see Note 2). The notch produces a stress concentration which promotes a brittle, rather than a ductile, fracture. The results of this test method are reported in terms of energy absorbed per unit of specimen width (see Note 3).  
Note 1: The machines with pendulum-type hammers have been standardized in that they must comply with certain requirements including a fixed height of hammer fall, which results in a substantially fixed velocity of the hammer at the moment of impact. Hammers of different initial energies (produced by varying their effective weights), however, are recommended for use with specimens of different impact resistance. Moreover, manufacturers of the equipment are permitted to use different lengths and constructions of pendulums with possible differences in pendulum rigidities resulting (see Section 5). Be aware that other differences in machine design do exist.
Note 2: The specimens are standardized in that they have a fixed length and fixed depth, however, the width of the specimens is permitted to vary between limits. One design of milled notch is allowed. The notch in the specimen serves to concentrate the stress, minimize plastic deformation, and direct the fracture to the part of the specimen behind the notch. Scatter in energy-to-break is thus reduced. Because of differences in the elastic and viscoelastic properties of plastics, however, response to a given notch varies among materials.
Note 3: Caution must be exercised in interpreting the results of this test method. The following testing parameters have been shown to affect test results significant...

General Information

• Status: Published
• Publication Date: 31-Mar-2018
• ICS: 83.140.01 - Rubber and plastics products in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.10 - Mechanical Properties

Relations

• Refers: ASTM D883-24 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2024
• Refers: ASTM D883-23 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2023
• Refers: ASTM D883-20 - Standard Terminology Relating to Plastics
• Effective Date: 01-Jan-2020
• Refers: ASTM D4066-13(2019) - Standard Classification System for Nylon Injection and Extrusion Materials (PA)
• Effective Date: 01-Nov-2019
• Refers: ASTM D883-19c - Standard Terminology Relating to Plastics
• Effective Date: 01-Aug-2019
• Refers: ASTM D883-19a - Standard Terminology Relating to Plastics
• Effective Date: 15-Apr-2019
• Refers: ASTM D883-19 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2019
• Refers: ASTM D883-18a - Standard Terminology Relating to Plastics
• Effective Date: 01-Dec-2018
• Refers: ASTM D883-18 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2018
• Refers: ASTM D883-17 - Standard Terminology Relating to Plastics
• Effective Date: 15-Aug-2017
• Refers: ASTM D4066-13 - Standard Classification System for Nylon Injection and Extrusion Materials (PA)
• Effective Date: 01-Jul-2013
• Refers: ASTM E691-13 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-May-2013
• Refers: ASTM D883-12e1 - Standard Terminology Relating to Plastics
• Effective Date: 15-Nov-2012
• Refers: ASTM D4000-12 - Standard Classification System for Specifying Plastic Materials
• Effective Date: 01-May-2012
• Refers: ASTM E691-11 - Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• Effective Date: 01-Nov-2011

Overview

ASTM D6110-18 is the internationally recognized standard test method for determining the Charpy impact resistance of notched specimens of plastics. Developed by ASTM International, this method assesses the resistance of plastic materials to breakage when subjected to flexural shock, as indicated by the energy absorbed during a single pendulum impact. By using standardized test specimens with a milled notch, this procedure promotes brittle fracture and provides essential data for quality control, material specification, and comparative material performance evaluation.

Key Topics

• Scope and Purpose

  • Determines impact resistance of plastics using notched specimens and a pendulum-type hammer.
  • Emphasizes the significance of material specifications, specimen preparation, conditioning, and testing parameters.

• Test Methodology

  • A notched specimen is placed as a horizontal simple beam and broken by a single swing of the pendulum, striking precisely opposite the notch.
  • The energy absorbed is calculated and reported per unit width of the specimen, enabling material comparison.

• Roles of the Notch and Specimen Preparation

  • A milled notch concentrates stress, promoting a brittle fracture and reducing variability in results.
  • Different materials and fabrication methods can affect how energy is absorbed and how the specimen fractures (brittle vs. ductile behavior).

• Factors Affecting Test Results

  • Critical aspects include specimen width, notching quality, material conditioning, and machine parameters.
  • The width of the specimen directly influences whether the fracture is brittle (low-energy) or ductile (high-energy).
  • Proper machine calibration and adherence to conditioning standards are vital for accuracy.

Applications

• Plastics Material Qualification

  • Used to certify material properties for specification sheets, purchase agreements, and engineering design.

• Quality Control

  • Identifies batch variances and ensures material consistency during manufacturing processes.

• Research and Development

  • Supports comparative studies between different plastics, formulations, or reinforcements.
  • Essential for understanding performance under impact and for troubleshooting failure modes.

• Comparison and Selection

  • Enables manufacturers and engineers to select appropriate plastic materials based on impact resistance requirements.
  • Results are useful for designing products subjected to sudden forces or potential shocks, such as automotive components, consumer electronics, and construction materials.

Related Standards

• ASTM D618 - Practice for Conditioning Plastics for Testing.
• ASTM D883 - Terminology Relating to Plastics.
• ASTM D4000 - Classification System for Specifying Plastic Materials.
• ASTM D5947 - Test Methods for Physical Dimensions of Solid Plastics Specimens.
• ASTM D4066 - Classification System for Nylon Injection and Extrusion Materials.
• ASTM E691 - Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method.

Practical Value

The ASTM D6110-18 standard provides a rigorous and repeatable method to determine the impact resistance of plastics, a crucial metric for product performance and safety in industries ranging from automotive to electronics. Its standardized approach aids in regulatory compliance, material certification, and the development of durable, high-performance polymer products. By aligning with this standard, organizations can ensure reliable material selection, fulfill quality requirements, and maintain global competitiveness in plastics engineering.

Keywords: ASTM D6110-18, Charpy impact resistance, plastics testing, notched specimens, flexural shock, quality control, polymer performance, standards compliance.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D6110 − 18
Standard Test Method for
Determining the Charpy Impact Resistance of Notched
Specimens of Plastics
This standard is issued under the fixed designation D6110; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.1 This test method is used to determine the resistance of
plastics to breakage by flexural shock as indicated by the
NOTE 4—This standard resembles ISO179 in title only. The content is
significantly different.
energy extracted from standardized (see Note 1) pendulum-
type hammers, mounted in standardized machines, in breaking
1.3 This international standard was developed in accor-
standard specimens with one pendulum swing. This test
dance with internationally recognized principles on standard-
methodrequiresspecimenstobemadewithamillednotch(see
ization established in the Decision on Principles for the
Note 2). The notch produces a stress concentration which
Development of International Standards, Guides and Recom-
promotes a brittle, rather than a ductile, fracture.The results of
mendations issued by the World Trade Organization Technical
this test method are reported in terms of energy absorbed per
Barriers to Trade (TBT) Committee.
unit of specimen width (see Note 3).
2. Referenced Documents
NOTE 1—The machines with pendulum-type hammers have been
standardizedinthattheymustcomplywithcertainrequirementsincluding 2.1 ASTM Standards:
a fixed height of hammer fall, which results in a substantially fixed
D618Practice for Conditioning Plastics for Testing
velocity of the hammer at the moment of impact. Hammers of different
D647Practice for Design of Molds for Test Specimens of
initialenergies(producedbyvaryingtheireffectiveweights),however,are
Plastic Molding Materials (Withdrawn 1994)
recommended for use with specimens of different impact resistance.
D883Terminology Relating to Plastics
Moreover, manufacturers of the equipment are permitted to use different
lengths and constructions of pendulums with possible differences in
D4000Classification System for Specifying Plastic Materi-
pendulum rigidities resulting (see Section 5). Be aware that other
als
differences in machine design do exist.
D4066Classification System for Nylon Injection and Extru-
NOTE 2—The specimens are standardized in that they have a fixed
sion Materials (PA)
length and fixed depth, however, the width of the specimens is permitted
to vary between limits. One design of milled notch is allowed. The notch D5947Test Methods for Physical Dimensions of Solid
in the specimen serves to concentrate the stress, minimize plastic
Plastics Specimens
deformation, and direct the fracture to the part of the specimen behind the
E691Practice for Conducting an Interlaboratory Study to
notch. Scatter in energy-to-break is thus reduced. Because of differences
Determine the Precision of a Test Method
in the elastic and viscoelastic properties of plastics, however, response to
a given notch varies among materials.
3. Terminology
NOTE 3—Caution must be exercised in interpreting the results of this
test method. The following testing parameters have been shown to affect
3.1 Definitions—For definitions related to plastics, see Ter-
test results significantly: method of specimen fabrication, including but
minology D883.
not limited to processing technology, molding conditions, mold design,
andthermaltreatment;methodofnotching;speedofnotchingtool;design
of notching apparatus; quality of the notch; time between notching and 4. Summary of Test Method
test; test specimen thickness; test specimen width under notch; and
4.1 Anotched specimen is supported as a horizontal simple
environmental conditioning.
beamandisbrokenbyasingleswingofthependulumwiththe
1.2 This standard does not purport to address all of the
impactlinemidwaybetweenthesupportsanddirectlyopposite
safety concerns, if any, associated with its use. It is the
the notch.
responsibility of the user of this standard to establish appro-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
This test method is under the jurisdiction ofASTM Committee D20 on Plastics contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved April 1, 2018. Published April 2018. Originally the ASTM website.
approved in 1997. Last previous edition approved in 2017 as D6110-17. DOI: The last approved version of this historical standard is referenced on
10.1520/D6110-18. www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6110 − 18
5. Significance and Use drawing down or necking and by a relatively low energy
absorption) or a ductile, high-energy break (as evidenced by
5.1 Before proceeding with this test method, refer to the
considerabledrawingorneckingdownintheregionbehindthe
material specification for the material being tested. Any test
notch and by a relatively high energy absorption) will occur, it
specimen preparation, conditioning, dimensions and testing
is necessary that the width be stated in the specification
parameters required by the materials specification shall take
covering that material and that the width be stated along with
precedence over those required by this test method. Table 1 of
the impact value.
Classification D4000 lists the ASTM materials standards that
currently exist. If there is no material specification, then the
5.7 This test method requires that the specimen break
requirements of this test method apply.
completely. Results obtained when testing materials with a
pendulum that does not have sufficient energy to complete the
5.2 The pendulum impact test indicates the energy to break
breaking of the extreme fibers and toss the broken pieces shall
standard test specimens of specified size under stipulated
be considered a departure from standard and shall not be
conditions of specimen mounting, notching (stress
reported as a standard result. Impact values cannot be directly
concentration), and pendulum velocity at impact.
compared for any two materials that experience different types
5.3 For this test method, the energy lost by the pendulum
of failure.
during the breakage of the specimen is the sum of the energies
5.8 The value of this impact test method lies mainly in the
required to initiate fracture of the specimen; to propagate the
areas of quality control and materials specification. If two
fracture across the specimen; to throw the free ends of the
groups of specimens of supposedly the same material show
broken specimen (toss energy); to bend the specimen; to
significantly different energy absorptions, critical widths, or
producevibrationinthependulumarm;toproducevibrationor
critical temperatures, it is permitted to assume that they were
horizontal movement of the machine frame or base; to over-
made of different materials or were exposed to different
come friction in the pendulum bearing and in the indicating
processing or conditioning environments. The fact that a
mechanism, and to overcome windage (pendulum air drag); to
material shows twice the energy absorption of another under
indent or deform, plastically, the specimen at the line of
these conditions of test does not indicate that this same
impact; and to overcome the friction caused by the rubbing of
relationship will exist under another set of test conditions.
the striking nose over the face of the bent specimen.
NOTE 5—The toss energy, or the energy used to throw the free ends of
the broken specimen, is suspected to represent a very large fraction of the
6. Apparatus
total energy absorbed when testing relatively dense and brittle materials.
6.1 Pendulum Impact Machine—The machine shall consist
No procedure has been established for estimating the toss energy for the
Charpy method.
of a massive base on which are mounted a pair of supports for
holding the specimen and to which is connected, through a
5.4 For tough, ductile, fiber-filled, or cloth-laminated
rigid frame and bearings, one of a number of pendulum-type
materials, the fracture propagation energy is usually large
hammers having an initial energy suitable for use with the
compared to the fracture initiation energy. When testing these
particular specimen to be tested (or one basic pendulum
materials, energy losses due to fracture propagation, vibration,
designed to accept add-on weights), plus a pendulum holding
friction between the striking nose and the specimen has the
and releasing mechanism and a mechanism for indicating the
potential to become quite significant, even when the specimen
breaking energy of the specimen. The specimen anvil,
is accurately machined and positioned, and the machine is in
pendulum, and frame shall be sufficiently rigid to maintain
goodconditionwithadequatecapacity(seeNote6).Significant
correctalignmentofthestrikingedgeandspecimen,bothatthe
energy losses due to bending and indentation when testing soft
moment of impact and during the propagation of the fracture,
materials have also been observed.
and to minimize energy losses due to vibration. The base shall
NOTE 6—Although the frame and the base of the machine must be
be sufficiently massive so that the impact will not cause it to
sufficiently rigid and massive to handle the energies of tough specimens
move. The machine shall be designed, constructed, and main-
without motion or excessive vibration, the pendulum arm cannot be made
tained so that energy losses due to pendulum air drag
very massive because the greater part of its mass must be concentrated
(windage), friction in the pendulum bearings, and friction and
nearitscenterofpercussionatitsstrikingnose.Locatingthestrikingnose
preciselyatthecenterofpercussionreducesthevibrationofthependulum
inertia in the indicating mechanism are held to a minimum.
arm when used with brittle specimens. Some losses due to pendulum arm
6.1.1 Pendulum—The simple pendulum shall consist of a
vibration(theamountvaryingwiththedesignofthependulum)willoccur
single or multi-membered arm with a bearing on one end and
with tough specimens even when the striking nose is properly positioned.
a head, containing the striking nose, on the other. Although a
5.5 In a well-designed machine of sufficient rigidity and
large proportion of the mass of the simple pendulum is
mass, the losses due to vibration and friction in the pendulum
concentrated in the head, the arm must be sufficiently rigid to
bearing and in the indicating mechanism will be very small.
maintain the proper clearances and geometric relationships
Vibrational losses are observed when wide specimens of tough
between the machine parts and the specimen and to minimize
materials are tested in machines of insufficient mass, or in
vibrational energy losses, which are always included in the
machines that are not securely fastened to a heavy base.
measured impact value. A machine with a simple pendulum
5.6 Sincethistestmethodpermitsavariationinthewidthof design is illustrated in Fig. 1. Instruments with a compound-
thespecimensandsincethewidthdictates,formanymaterials, pendulum design also have been found to be acceptable for
whetherabrittle,low-energybreak(asevidencedbylittleorno use. A compound-pendulum design is illustrated in Fig. 2.
D6110 − 18
FIG. 1 Simple Beam (Charpy-Type) Impact Machine
FIG. 2 Example of Compound–Pendulum–Type Machine
6.1.1.1 The machine shall be provided with a basic pendu-
where:
lum capable of delivering an energy of 2.7 6 0.14 J (2.0 6
L = distance from the axis of support to the center of
0.10 ft-lbf). This pendulum shall be used for specimens that
percussion, m,
extract less than 85% of this energy when breaking a speci-
g = localgravitationalacceleration(knowntoanaccuracyof
men. Heavier pendulums or additional weights designed to
one part in one thousand), m/s
attach to the basic pendulum shall be provided for specimens
π = 3.1416 (4π = 39.48), and
that require more energy to break.Aseries of pendulums such
p = period, in s, of a single complete swing (to and fro)
that each has twice the energy of the next lighter one has been
determined from at least 20 consecutive and uninter-
found convenient.
rupted swings. The angle of swing shall be less than 5°
6.1.1.2 The effective length of the pendulum shall be
each side of center.
between 0.325 and 0.406 m (12.8 and 16.0 in.) so that the
6.1.3 Pendulum Holding and Releasing Mechanism—The
requiredelevationofthestrikingnoseisobtainedbyraisingthe
mechanismshallbedesigned,constructed,andoperatedsothat
pendulumtoananglebetween60and30°abovethehorizontal.
it will release the pendulum without imparting acceleration or
6.1.2 Striking Edge—The striking edge (nose) of the pen-
vibration to the pendulum. The position of the pendulum
dulum shall be made of hardened steel, tapered to have an
holdingandreleasingmechanismshallbesuchthatthevertical
included angle of 45 6 2° and shall be rounded to a radius of
height of fall of the striking nose shall be 610 6 2 mm (24.0
3.17 6 0.12 mm (0.125 6 0.005 in.). The pendulum shall be
6 0.1 in.). This will produce a velocity of the striking nose at
aligned in such a way that when it is in its free hanging
the moment of impact of approximately 3.46 m (11.4 ft)/s as
position, the center of percussion of the pendulum shall lie
determined by the following equation:
within 62.54mm(0.10in.)ofthemiddleofthelineofcontact
madebythestrikingnoseuponthefaceofastandardspecimen
v 5 =2gh (2)
of square cross section. The distance from the axis of support
where:
to the center of percussion is determined experimentally from
the period of motion of small amplitude oscillations of the
v = velocity of the striking nose at the moment of impact,
g = local gravitational acceleration, and
pendulum by means of the following equation:
h = vertical height of fall of the striking nose.
2 2
L 5 g/4π p (1)
~ !
D6110 − 18
for friction and windage. Instructions for making these correc-
tions are found in Annex A1 and Annex A2. Many digital
indicating systems automatically correct for windage and
friction. Consult the equipment manufacturer for information
on how this is performed.
6.1.6 Appendix X2 describes a calibration procedure for
establishing the accuracy of the equipment. A check of the
calibration of an impact machine is difficult to make under
dynamic conditions. The basic parameters normally are
checked under static conditions. If the machine passes the
static tests, then it is assumed to be accurate. Appendix X2,
however, also describes a dynamic test for checking certain
features of the machine and specimen. Some machine designs
require a change to the recommended method of obtaining the
requiredcalibrationmeasurements.Contactthemachinemanu-
facturer to determine if additional instructions for adjusting a
particular machine are available. Other methods of performing
the required checks are acceptable provided that they are
proven to result in an equivalent accuracy.
6.2 Specimen Notching Machine—Notching shall be done
on a milling machine, engine lathe, or other suitable machine
tool. A carbide-tipped or industrial diamond-tipped notching
cutterisrecommended.Bothcutterspeedandfeedrateshallbe
controllable. Provision for cooling the specimen is recom-
mended. Water and compressed air are suitable coolants for
many plastics.
6.2.1 The profile of the cutting tooth or teeth shall be such
FIG. 3 Relationship of Anvil, Specimen, and Striking Edge to
Each Other for Charpy Test Method as to produce a notch in the test specimen of the contour and
depthspecifiedinFig.4andinthemannerspecifiedinSection
8.
This assumes no windage or friction.
6.2.2 A single-tooth cutter shall be used for notching the
6.1.4 Specimen Supports—The test specimen shall be sup-
specimen, unless it is demonstrated that notches of an equiva-
ported against two rigid anvils in such a position that its center
lentqualityareproducedwithamulti-toothcutter.Single-tooth
ofgravityandthecenterofthenotchshalllieontangenttothe
cutters are preferred because of the ease of grinding the cutter
arcoftravelofthecenterofpercussionofthependulumdrawn
tothespecimencontourandbecauseofthesmoothercutonthe
at the position of impact. The edges of the anvils shall be
specimen. The cutting edge shall be ground and honed care-
roundedtoaradiusof3.17 60.12mm(0.125 60.005in.)and
fully to ensure sharpness and freedom from nicks and burrs.
the anvils’ lines of contact (span) with the specimen shall be
Tools with no rake and a work relief angle of 15 to 20° have
101.6 6 0.5 mm (4.0 6 0.02 in.) apart (see Fig. 3). Some
been found satisfactory.
machine manufacturers supply a jig for positioning the speci-
men on the supports. 6.3 Micrometers—Apparatus for measurement of the width
of the specimen shall comply with the requirements of Test
NOTE 7—Some machines currently in use employ a 108.0-mm span.
4 Methods D5947. Apparatus for the measurement of the depth
Data obtained under these conditions are valid.
of plastic material remaining in the specimen under the notch
6.1.5 Indicator—Means shall be provided for determining
shall comply with requirements of Test Methods D5947,
the energy expended by the pendulum in breaking the speci-
provided however that the one anvil or presser foot shall be a
men. This is accomplished using either a pointer and dial
tapered blade conforming to the dimensions given in Fig. 5.
mechanism or an electronic system consisting of a digital
Theopposinganvilorpresserfootshallbeflatandconforming
indicator and sensor (typically an encoder or resolver). In
to Test Methods D5947.
either case, the indicated breaking energy is determined by
detecting the height of rise of the pendulum beyond the point
7. Test Specimen
of impact in terms of energy removed from that specific
7.1 The test specimen shall conform to the dimensions and
pendulum. The indicated remaining energy must be corrected
geometry of Fig. 4, except as modified in accordance with 7.2
for pendulum bearing friction, pointer friction, pointer inertia,
– 7.5. To ensure the correct contour and conditions of the
and pendulum windage. Some equipment manufacturers pro-
specified notch, all specimens shall be notched in accordance
vide graphs or tables to aid in the calculation of the correction
with Section 8.
7.2 Molded specimens shall have a width between 3.00 and
Supporting data have been filed atASTM International Headquarters and may
be obtained by requesting Research Report RR:D20-1033. 12.7 mm (0.118 and 0.500 in.). Use the specimen width as
D6110 − 18
mm in.
A 10.16 ± 0.05 0.400 ± 0.002
B 63.5 max 2.50 max
61.0 min 2.40 min
C 127.0 max 5.00 max
124.5 min 4.90 min
D 0.25R ± 0.05 0.010R ± 0.002
E 12.70 ± 0.15 0.500 ± 0.006
FIG. 4 Dimensions of Simple Beam, Charpy Type, Impact Test Specimen
thatcooperatinglaboratoriesagreeonstandardmoldsconform-
ing to Practice D647, and upon a standard molding procedure
for the material under investigation.
7.2.2 A critical investigation of the mechanics of impact
testing has shown that tests made upon specimens under 6.35
mm (0.250 in.) in width absorb more energy due to crushing,
bending, and twisting than do wider specimens. Specimens
6.35 mm (0.250 in.) or over in width are therefore recom-
mended. The responsibility for determining the minimum
specimen width shall be the investigator’s, with due reference
to the specification for that material.
7.2.3 The impact resistance of a plastic material will be
differentifthenotchisperpendicularto,ratherthanparallelto,
the direction of molding.
7.3 For sheet materials, the specimens shall be cut from the
sheet in both the lengthwise and crosswise directions unless
otherwise specified. The width of the specimen shall be the
thicknessofthesheetifthesheetthicknessisbetween3.00and
12.7mm(0.118and0.500in.).Sheetmaterialthickerthan12.7
FIG. 5 Notch Depth Measurement on Test Specimens
mm(0.500in.)shallbemachineddownto12.7mm(0.500in.).
It is acceptable to test specimens with a 12.7-mm (0.500-in.)
squarecrosssectioneitheredgewiseorflatwiseascutfromthe
specified in the material specification or as agreed upon
sheet. When specimens are tested flatwise, the notch shall be
between the supplier and the customer.
made on the machined surface if the specimen is machined on
7.2.1 The type of mold and molding machine used and the
one face only. When the specimen is cut from a thick sheet,
flow behavior in the mold cavity will influence the strength
notation shall be made of the portion of the thickness of the
obtained. It is possible that results from a specimen taken from
sheet from which the specimen was cut, for example, center,
one end of a molded bar will give different results than a
specimen taken from the other end. It is therefore important top, or bottom surface.
D6110 − 18
7.3.1 The impact resistance of a plastic material will be specimen are verified. There is evidence that the contour of
differentifthenotchisperpendicularto,ratherthanparallelto, notches cut in materials of widely differing physical properties
the grain of an anisotropic bar cut from a sheet. Specimens cut bythesamecutterwilldiffer.Itissometimesnecessarytoalter
from sheets that are suspected of being anisotropic shall be the cutter dimensions in order to produce the required notch
prepared and tested both lengthwise and crosswise to the contour for certain materials.
direction of the anisotropy. 8.1.2 A notching operation notches one or more specimens
plus the “dummy bars”. Examine the notch produced on the
7.4 The practice of cementing, bolting, clamping, or other-
specimenbyeachcutterafterevery500notchingoperationsor
wise combining specimens of substandard width to form a
less frequently if experience shows this to be acceptable. The
composite test specimen is not recommended since test results
specimen used to verify the notch shall be the same material
will be seriously affected by interface effects or effects of
that is being prepared for testing. Inspect and verify the notch
solvents and cements on energy absorption of composite test
in the specimen. If the angle or radius of the notch does not
specimens, or both. If Charpy test data on such thin materials
meet the requirements of 8.1, the cutter shall be replaced. One
are required, however, and if possible sources of error are
procedure for inspecting and verifying the notch is provided in
recognized and acceptable, the following technique of prepar-
Appendix X1.
ingcompositesoughttobeutilized.Thetestspecimensshallbe
a composite of individual thin specimens totaling 6.35 to 12.7 NOTE 9—The contour of the notch made using multi-tooth cutters is
checkedbymeasuringthecontourofthenotchonastripofsoftmetalthat
mm (0.125 to 0.500 in.) in width. Individual members of the
is inserted between two specimens during the notching process.
composite shall be aligned accurately with each other and
NOTE 10—When the same material is being tested on a repetitive basis,
clamped, bolted, or cemented together. Care must be taken to
and it is demonstrated that the notch in the specimen takes the contour of
select a solvent or adhesive that will not affect the impact
the tip of the cutter and that the notch meets the contour requirements
when checked in accordance with Appendix X1, then it is acceptable to
resistanceofthematerialundertest.Ifsolventsorsolvent–con-
check the contour of the tip of the cutter instead of the notch in the
tainingadhesivesareemployed,aconditioningprocedureshall
specimen.
be established to ensure complete removal of the solvent prior
8.2 Notch Depth—The depth of the plastic material remain-
to test. The composite specimens shall be machined to proper
ing in the specimen under the notch shall be 10.16 6 0.05 mm
dimensions and then notched. In all such cases, the use of
(0.400 6 0.002 in.). This dimension shall be measured with
compositespecimensshallbenotedinthereportoftestresults.
apparatus in accordance with 6.3. The tapered blade will be
7.5 Each specimen shall be free of twist and shall be
fittedtothenotch.Thespecimenwillbeapproximatelyvertical
bounded by mutually perpendicular pairs of plane, paralleled
between the anvils. Position the edge of the non-cavity (wider
surfaces and free from scratches, pits, and sink marks. The
edge) surface centered on the micrometer’s flat circular anvil.
specimens shall be checked for conformity with these require-
8.3 Cutter Speed and Feed Rate—Select the cutter speed
ments by visual observation against straight edges, squares or
and feed speed based on the material being tested. The quality
flat plates, and by measuring with micrometer calipers. Any
ofthenotchwillbeadverselyaffectedbythermaldeformations
specimen showing observable or measurable departure from
and stresses induced during the cutting operation if proper
one or more of these requirements shall be rejected or
conditions are not selected. The notching parameters used
machined to the proper size and shape before testing. A
shall not alter the physical state of the material, such as by
specimen that has a slight twist to its notched face of 0.05 mm
raising the temperature of a thermoplastic above its glass
(0.002 in.) at the point of contact with the pendulum striking
transition temperature.
edgewillbelikelytohaveacharacteristicfracturesurfacewith
8.3.1 In general, high cutter speeds, slow feed rates, and
considerable greater fracture area than for a normal break. In
lackofcoolantinducemorethermaldamagethanaslowcutter
this case, the energy to break and toss the broken section will
speed,fastfeedspeed,andtheuseofacoolant.Toohighafeed
be considerably larger (20 to 30%) than for a normal break.
speed/cutter speed ratio, however, has been shown to cause
impacting and cracking of the specimen. The range of cutter
8. Notching Test Specimens
speed/feed ratios possible to produce acceptable notches has
NOTE 8—When testing a material for the first time, it is necessary to
study the effect of all variations in the notching conditions, including been shown to be extended by the use of a suitable coolant.
cutter dimensions, notch depth, cutter speed, and feed rate. To establish
8.3.1.1 Forsomethermoplastics,suitablenotcheshavebeen
that the notching parameters are suitable, it is advisable to notch several
produced using cutter speeds from 54 to 150 m/min and a feed
specimens of the material and inspect both the tool entrance and tool exit
rateof89to160mm/minwithoutawatercoolant.Satisfactory
side of each notched specimen, in accordance with Appendix X1.Adjust
notches also have been produced using the same cutter speeds
the notching machine as required. The specimens used to determine
notching conditions shall not be used to make determinations of impact at feed speeds of from 36 to 160 mm/min with water coolant.
resistance.
8.3.1.2 Embedded thermocouples have been used to deter-
mine the temperature rise in the material near the apex of the
8.1 Notch Dimensions—The included angle of the notch
notch during machining. Thermal stresses induced during the
shall be 45 6 1° with a radius of curvature at the apex of 0.25
notchingoperationhavebeenobservedintransparentmaterials
6 0.05 mm (0.010 6 0.002 in.). The plane bisecting the notch
byviewingthespecimenatlowmagnificationbetweencrossed
angle shall be perpendicular to the face of the test specimen
within 2°.
8.1.1 Thenotchisacriticalfactorofthistest.Itisextremely
Supporting data have been filed atASTM International Headquarters and may
important, therefore, that dimensions of the notch in the be obtained by requesting Research Report RR:D20-1066.
D6110 − 18
polars in monochromatic light. The specimens used to deter- therearenoconditioningrequirementsdetailedinthematerials
minetemperatureriseshallnotbeusedtomakedeterminations specification, follow the conditioning requirements in Section
of impact resistance. 9.
8.3.2 The feed rate and the cutter speed shall remain
10.2 Machine Preparation:
constant throughout the notching operation.
10.2.1 Estimate the breaking energy for the sample and
select a pendulum of suitable energy. Select the lightest
8.4 It is acceptable to notch specimens individually or in a
standard pendulum that is expected to break all specimens in
group.Ineithercase,however,anunnotchedbackupordummy
the group with an energy loss of not more than 85% of its
bar shall be placed behind the last specimen in the sample
capacity (see 6.1). If the breaking energy cannot be estimated,
holder to prevent distortion and chipping by the cutter as it
select the correct pendulum by performing trial runs. Use
exits from the last test specimen.
caution to avoid damaging the pendulum by selecting a
8.5 All specimens having one dimension less than 12.7 mm
pendulum that is too light for a particular sample.
(0.500 in.) shall have the notch cut on the shorter side.
NOTE 11—Ideally, an impact test would be conducted at a constant test
Compression molded specimens shall be notched on the side
velocity. In a pendulum-type test, however, the velocity decreases as the
paralleltothedirectionofapplicationofmoldingpressure.The
fracture progresses. For specimens that have an impact energy approach-
ing the capacity of the pendulum, there is insufficient energy to complete
impact resistance of a plastic material will be different if the
thebreakandtoss.Byavoidingthehigher15%scaleenergyreadings,the
notch is perpendicular to rather than parallel to the direction of
velocityofthependulumwillnotbereducedbelow1.33m/s.Ontheother
molding, as with or across the grain of an anisotropic bar cut
hand,theuseofapendulumthatistooheavywouldreducethesensitivity
from a plate.
of the reading.
10.2.2 After installing the selected pendulum on the
9. Conditioning
machine, check the machine for conformity with the require-
ments of Section 6 before starting the tests.
9.1 Check the materials specification for the material that is
10.2.3 When using a machine equipped with a pointer and
being tested. If there are no conditioning requirements stated
dial mechanism or an electronic indicator that does not
by the materials specification, the test specimens shall be
automatically correct for windage and friction, determine the
conditioned for not less than 40 h after notching and prior to
windage and friction correction factors for the machine before
testinginaccordancewithProcedureAofPracticeD618unless
testing specimens. Windage and friction correction factors
documented (between supplier and customer) that shorter
shall be determined on a daily basis and shall be calculated
conditioning time is sufficient for a given material to rea
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D6110 − 17 D6110 − 18
Standard Test Method for
Determining the Charpy Impact Resistance of Notched
Specimens of Plastics
This standard is issued under the fixed designation D6110; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This test method is used to determine the resistance of plastics to breakage by flexural shock as indicated by the energy
extracted from standardized (see Note 1) pendulum-type hammers, mounted in standardized machines, in breaking standard
specimens with one pendulum swing. This test method requires specimens to be made with a milled notch (see Note 2). The notch
produces a stress concentration which promotes a brittle, rather than a ductile, fracture. The results of this test method are reported
in terms of energy absorbed per unit of specimen width (see Note 3).
NOTE 1—The machines with pendulum-type hammers have been standardized in that they must comply with certain requirements including a fixed
height of hammer fall, which results in a substantially fixed velocity of the hammer at the moment of impact. Hammers of different initial energies
(produced by varying their effective weights), however, are recommended for use with specimens of different impact resistance. Moreover, manufacturers
of the equipment are permitted to use different lengths and constructions of pendulums with possible differences in pendulum rigidities resulting (see
Section 5). Be aware that other differences in machine design do exist.
NOTE 2—The specimens are standardized in that they have a fixed length and fixed depth, however, the width of the specimens is permitted to vary
between limits. One design of milled notch is allowed. The notch in the specimen serves to concentrate the stress, minimize plastic deformation, and direct
the fracture to the part of the specimen behind the notch. Scatter in energy-to-break is thus reduced. Because of differences in the elastic and viscoelastic
properties of plastics, however, response to a given notch varies among materials.
NOTE 3—Caution must be exercised in interpreting the results of this test method. The following testing parameters have been shown to affect test
results significantly: method of specimen fabrication, including but not limited to processing technology, molding conditions, mold design, and thermal
treatment; method of notching; speed of notching tool; design of notching apparatus; quality of the notch; time between notching and test; test specimen
thickness; test specimen width under notch; and environmental conditioning.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
NOTE 4—This standard resembles ISO 179 in title only. The content is significantly different.
1.3 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D618 Practice for Conditioning Plastics for Testing
D647 Practice for Design of Molds for Test Specimens of Plastic Molding Materials (Withdrawn 1994)
D883 Terminology Relating to Plastics
D4000 Classification System for Specifying Plastic Materials
D4066 Classification System for Nylon Injection and Extrusion Materials (PA)
D5947 Test Methods for Physical Dimensions of Solid Plastics Specimens
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions—For definitions related to plastics, see Terminology D883.
This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.
Current edition approved Dec. 1, 2017April 1, 2018. Published January 2018April 2018. Originally approved in 1997. Last previous edition approved in 20102017 as
D6110 - 10.D6110 - 17. DOI: 10.1520/D6110-17.10.1520/D6110-18.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6110 − 18
4. Summary of Test Method
4.1 A notched specimen is supported as a horizontal simple beam and is broken by a single swing of the pendulum with the
impact line midway between the supports and directly opposite the notch.
5. Significance and Use
5.1 Before proceeding with this test method, refer to the material specification for the material being tested. Any test specimen
preparation, conditioning, dimensions and testing parameters required by the materials specification shall take precedence over
those required by this test method. Table 1 of Classification D4000 lists the ASTM materials standards that currently exist. If there
is no material specification, then the requirements of this test method apply.
5.2 The pendulum impact test indicates the energy to break standard test specimens of specified size under stipulated conditions
of specimen mounting, notching (stress concentration), and pendulum velocity at impact.
5.3 For this test method, the energy lost by the pendulum during the breakage of the specimen is the sum of the energies required
to initiate fracture of the specimen; to propagate the fracture across the specimen; to throw the free ends of the broken specimen
(toss energy); to bend the specimen; to produce vibration in the pendulum arm; to produce vibration or horizontal movement of
the machine frame or base; to overcome friction in the pendulum bearing and in the indicating mechanism, and to overcome
windage (pendulum air drag); to indent or deform, plastically, the specimen at the line of impact; and to overcome the friction
caused by the rubbing of the striking nose over the face of the bent specimen.
NOTE 5—The toss energy, or the energy used to throw the free ends of the broken specimen, is suspected to represent a very large fraction of the total
energy absorbed when testing relatively dense and brittle materials. No procedure has been established for estimating the toss energy for the Charpy
method.
5.4 For tough, ductile, fiber-filled, or cloth-laminated materials, the fracture propagation energy is usually large compared to the
fracture initiation energy. When testing these materials, energy losses due to fracture propagation, vibration, friction between the
striking nose and the specimen has the potential to become quite significant, even when the specimen is accurately machined and
positioned, and the machine is in good condition with adequate capacity (see Note 6). Significant energy losses due to bending and
indentation when testing soft materials have also been observed.
NOTE 6—Although the frame and the base of the machine must be sufficiently rigid and massive to handle the energies of tough specimens without
motion or excessive vibration, the pendulum arm cannot be made very massive because the greater part of its mass must be concentrated near its center
of percussion at its striking nose. Locating the striking nose precisely at the center of percussion reduces the vibration of the pendulum arm when used
with brittle specimens. Some losses due to pendulum arm vibration (the amount varying with the design of the pendulum) will occur with tough specimens
even when the striking nose is properly positioned.
5.5 In a well-designed machine of sufficient rigidity and mass, the losses due to vibration and friction in the pendulum bearing
and in the indicating mechanism will be very small. Vibrational losses are observed when wide specimens of tough materials are
tested in machines of insufficient mass, or in machines that are not securely fastened to a heavy base.
5.6 Since this test method permits a variation in the width of the specimens and since the width dictates, for many materials,
whether a brittle, low-energy break (as evidenced by little or no drawing down or necking and by a relatively low energy
absorption) or a ductile, high-energy break (as evidenced by considerable drawing or necking down in the region behind the notch
and by a relatively high energy absorption) will occur, it is necessary that the width be stated in the specification covering that
material and that the width be stated along with the impact value.
5.7 This test method requires that the specimen break completely. Results obtained when testing materials with a pendulum that
does not have sufficient energy to complete the breaking of the extreme fibers and toss the broken pieces shall be considered a
departure from standard and shall not be reported as a standard result. Impact values cannot be directly compared for any two
materials that experience different types of failure.
5.8 The value of this impact test method lies mainly in the areas of quality control and materials specification. If two groups
of specimens of supposedly the same material show significantly different energy absorptions, critical widths, or critical
temperatures, it is permitted to assume that they were made of different materials or were exposed to different processing or
conditioning environments. The fact that a material shows twice the energy absorption of another under these conditions of test
does not indicate that this same relationship will exist under another set of test conditions.
6. Apparatus
6.1 Pendulum Impact Machine—The machine shall consist of a massive base on which are mounted a pair of supports for
holding the specimen and to which is connected, through a rigid frame and bearings, one of a number of pendulum-type hammers
having an initial energy suitable for use with the particular specimen to be tested (or one basic pendulum designed to accept add-on
weights), plus a pendulum holding and releasing mechanism and a mechanism for indicating the breaking energy of the specimen.
The specimen anvil, pendulum, and frame shall be sufficiently rigid to maintain correct alignment of the striking edge and
specimen, both at the moment of impact and during the propagation of the fracture, and to minimize energy losses due to vibration.
The base shall be sufficiently massive so that the impact will not cause it to move. The machine shall be designed, constructed,
D6110 − 18
and maintained so that energy losses due to pendulum air drag (windage), friction in the pendulum bearings, and friction and inertia
in the indicating mechanism are held to a minimum.
6.1.1 Pendulum—The simple pendulum shall consist of a single or multi-membered arm with a bearing on one end and a head,
containing the striking nose, on the other. Although a large proportion of the mass of the simple pendulum is concentrated in the
head, the arm must be sufficiently rigid to maintain the proper clearances and geometric relationships between the machine parts
and the specimen and to minimize vibrational energy losses, which are always included in the measured impact value. A machine
with a simple pendulum design is illustrated in Fig. 1. Instruments with a compound-pendulum design also have been found to
be acceptable for use. A compound-pendulum design is illustrated in Fig. 2.
6.1.1.1 The machine shall be provided with a basic pendulum capable of delivering an energy of 2.7 6 0.14 J (2.0 6 0.10 ft-lbf).
This pendulum shall be used for specimens that extract less than 85 % of this energy when breaking a specimen. Heavier
pendulums or additional weights designed to attach to the basic pendulum shall be provided for specimens that require more energy
to break. A series of pendulums such that each has twice the energy of the next lighter one has been found convenient.
6.1.1.2 The effective length of the pendulum shall be between 0.325 and 0.406 m (12.8 and 16.0 in.) so that the required
elevation of the striking nose is obtained by raising the pendulum to an angle between 60 and 30° above the horizontal.
6.1.2 Striking Edge—The striking edge (nose) of the pendulum shall be made of hardened steel, tapered to have an included
angle of 45 6 2° and shall be rounded to a radius of 3.17 6 0.12 mm (0.125 6 0.005 in.). The pendulum shall be aligned in such
a way that when it is in its free hanging position, the center of percussion of the pendulum shall lie within 62.54 mm (0.10 in.)
of the middle of the line of contact made by the striking nose upon the face of a standard specimen of square cross section. The
distance from the axis of support to the center of percussion is determined experimentally from the period of motion of small
amplitude oscillations of the pendulum by means of the following equation:
2 2
L 5 ~g/4π ! p (1)
where:
L = distance from the axis of support to the center of percussion, m,
g = local gravitational acceleration (known to an accuracy of one part in one thousand), m/s
π = 3.1416 (4π = 39.48), and
FIG. 1 Simple Beam (Charpy-Type) Impact Machine
D6110 − 18
FIG. 2 Example of Compound–Pendulum–Type Machine
p = period, in s, of a single complete swing (to and fro) determined from at least 20 consecutive and uninterrupted swings. The
angle of swing shall be less than 5° each side of center.
6.1.3 Pendulum Holding and Releasing Mechanism—The mechanism shall be designed, constructed, and operated so that it will
release the pendulum without imparting acceleration or vibration to the pendulum. The position of the pendulum holding and
releasing mechanism shall be such that the vertical height of fall of the striking nose shall be 610 6 2 mm (24.0 6 0.1 in.). This
will produce a velocity of the striking nose at the moment of impact of approximately 3.46 m (11.4 ft)/s as determined by the
following equation:
v 5=2gh (2)
where:
v = velocity of the striking nose at the moment of impact,
g = local gravitational acceleration, and
h = vertical height of fall of the striking nose.
This assumes no windage or friction.
6.1.4 Specimen Supports—The test specimen shall be supported against two rigid anvils in such a position that its center of
gravity and the center of the notch shall lie on tangent to the arc of travel of the center of percussion of the pendulum drawn at
the position of impact. The edges of the anvils shall be rounded to a radius of 3.17 6 0.12 mm (0.125 6 0.005 in.) and the anvils’
lines of contact (span) with the specimen shall be 101.6 6 0.5 mm (4.0 6 0.02 in.) apart (see Fig. 3). Some machine manufacturers
supply a jig for positioning the specimen on the supports.
NOTE 7—Some machines currently in use employ a 108.0-mm span. Data obtained under these conditions are valid.
Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D20-1033.
D6110 − 18
FIG. 3 Relationship of Anvil, Specimen, and Striking Edge to Each Other for Charpy Test Method
6.1.5 Indicator—Means shall be provided for determining the energy expended by the pendulum in breaking the specimen. This
is accomplished using either a pointer and dial mechanism or an electronic system consisting of a digital indicator and sensor
(typically an encoder or resolver). In either case, the indicated breaking energy is determined by detecting the height of rise of the
pendulum beyond the point of impact in terms of energy removed from that specific pendulum. The indicated remaining energy
must be corrected for pendulum bearing friction, pointer friction, pointer inertia, and pendulum windage. Some equipment
manufacturers provide graphs or tables to aid in the calculation of the correction for friction and windage. Instructions for making
these corrections are found in Annex A1 and Annex A2. Many digital indicating systems automatically correct for windage and
friction. Consult the equipment manufacturer for information on how this is performed.
6.1.6 Appendix X2 describes a calibration procedure for establishing the accuracy of the equipment. A check of the calibration
of an impact machine is difficult to make under dynamic conditions. The basic parameters normally are checked under static
conditions. If the machine passes the static tests, then it is assumed to be accurate. Appendix X2, however, also describes a dynamic
test for checking certain features of the machine and specimen. For some machine designs, it might be necessary to change Some
machine designs require a change to the recommended method of obtaining the required calibration measurements. Contact the
machine manufacturer to determine if additional instructions for adjusting a particular machine are available. Other methods of
performing the required checks are acceptable provided that they are proven to result in an equivalent accuracy.
6.2 Specimen Notching Machine—Notching shall be done on a milling machine, engine lathe, or other suitable machine tool.
A carbide-tipped or industrial diamond-tipped notching cutter is recommended. Both cutter speed and feed rate shall be
controllable. Provision for cooling the specimen is recommended. Water and compressed air are suitable coolants for many
plastics.
6.2.1 The profile of the cutting tooth or teeth shall be such as to produce a notch in the test specimen of the contour and depth
specified in Fig. 4 and in the manner specified in Section 8.
6.2.2 A single-tooth cutter shall be used for notching the specimen, unless it is demonstrated that notches of an equivalent
quality are produced with a multi-tooth cutter. Single-tooth cutters are preferred because of the ease of grinding the cutter to the
specimen contour and because of the smoother cut on the specimen. The cutting edge shall be ground and honed carefully to ensure
sharpness and freedom from nicks and burrs. Tools with no rake and a work relief angle of 15 to 20° have been found satisfactory.
6.3 Micrometers—Apparatus for measurement of the width of the specimen shall comply with the requirements of Test Methods
D5947. Apparatus for the measurement of the depth of plastic material remaining in the specimen under the notch shall comply
with requirements of Test Methods D5947, provided however that the one anvil or presser foot shall be a tapered blade conforming
to the dimensions given in Fig. 5. The opposing anvil or presser foot shall be flat and conforming to Test Methods D5947.
D6110 − 18
mm in.
A 10.16 ± 0.05 0.400 ± 0.002
B 63.5 max 2.50 max
61.0 min 2.40 min
C 127.0 max 5.00 max
124.5 min 4.90 min
D 0.25R ± 0.05 0.010R ± 0.002
E 12.70 ± 0.15 0.500 ± 0.006
FIG. 4 Dimensions of Simple Beam, Charpy Type, Impact Test Specimen
FIG. 5 Notch Depth Measurement on Test Specimens
7. Test Specimen
7.1 The test specimen shall conform to the dimensions and geometry of Fig. 4, except as modified in accordance with 7.2 – 7.5.
To ensure the correct contour and conditions of the specified notch, all specimens shall be notched in accordance with Section 8.
7.2 Molded specimens shall have a width between 3.00 and 12.7 mm (0.118 and 0.500 in.). Use the specimen width as specified
in the material specification or as agreed upon between the supplier and the customer.
7.2.1 The type of mold and molding machine used and the flow behavior in the mold cavity will influence the strength obtained.
It is possible that results from a specimen taken from one end of a molded bar will give different results than a specimen taken
D6110 − 18
from the other end. It is therefore important that cooperating laboratories agree on standard molds conforming to Practice D647,
and upon a standard molding procedure for the material under investigation.
7.2.2 A critical investigation of the mechanics of impact testing has shown that tests made upon specimens under 6.35 mm
(0.250 in.) in width absorb more energy due to crushing, bending, and twisting than do wider specimens. Specimens 6.35 mm
(0.250 in.) or over in width are therefore recommended. The responsibility for determining the minimum specimen width shall be
the investigator’s, with due reference to the specification for that material.
7.2.3 The impact resistance of a plastic material will be different if the notch is perpendicular to, rather than parallel to, the
direction of molding.
7.3 For sheet materials, the specimens shall be cut from the sheet in both the lengthwise and crosswise directions unless
otherwise specified. The width of the specimen shall be the thickness of the sheet if the sheet thickness is between 3.00 and 12.7
mm (0.118 and 0.500 in.). Sheet material thicker than 12.7 mm (0.500 in.) shall be machined down to 12.7 mm (0.500 in.). It is
acceptable to test specimens with a 12.7-mm (0.500-in.) square cross section either edgewise or flatwise as cut from the sheet.
When specimens are tested flatwise, the notch shall be made on the machined surface if the specimen is machined on one face only.
When the specimen is cut from a thick sheet, notation shall be made of the portion of the thickness of the sheet from which the
specimen was cut, for example, center, top, or bottom surface.
7.3.1 The impact resistance of a plastic material will be different if the notch is perpendicular to, rather than parallel to, the grain
of an anisotropic bar cut from a sheet. Specimens cut from sheets that are suspected of being anisotropic shall be prepared and
tested both lengthwise and crosswise to the direction of the anisotropy.
7.4 The practice of cementing, bolting, clamping, or otherwise combining specimens of substandard width to form a composite
test specimen is not recommended since test results will be seriously affected by interface effects or effects of solvents and cements
on energy absorption of composite test specimens, or both. If Charpy test data on such thin materials are required, however, and
if possible sources of error are recognized and acceptable, the following technique of preparing composites ought to be utilized.
The test specimens shall be a composite of individual thin specimens totaling 6.35 to 12.7 mm (0.125 to 0.500 in.) in width.
Individual members of the composite shall be aligned accurately with each other and clamped, bolted, or cemented together. Care
must be taken to select a solvent or adhesive that will not affect the impact resistance of the material under test. If solvents or
solvent–containing adhesives are employed, a conditioning procedure shall be established to ensure complete removal of the
solvent prior to test. The composite specimens shall be machined to proper dimensions and then notched. In all such cases, the
use of composite specimens shall be noted in the report of test results.
7.5 Each specimen shall be free of twist and shall be bounded by mutually perpendicular pairs of plane, paralleled surfaces and
free from scratches, pits, and sink marks. The specimens shall be checked for conformity with these requirements by visual
observation against straight edges, squares or flat plates, and by measuring with micrometer calipers. Any specimen showing
observable or measurable departure from one or more of these requirements shall be rejected or machined to the proper size and
shape before testing. A specimen that has a slight twist to its notched face of 0.05 mm (0.002 in.) at the point of contact with the
pendulum striking edge will be likely to have a characteristic fracture surface with considerable greater fracture area than for a
normal break. In this case, the energy to break and toss the broken section will be considerably larger (20 to 30 %) than for a normal
break.
8. Notching Test Specimens
NOTE 8—When testing a material for the first time, it is necessary to study the effect of all variations in the notching conditions, including cutter
dimensions, notch depth, cutter speed, and feed rate. To establish that the notching parameters are suitable, it is advisable to notch several specimens of
the material and inspect both the tool entrance and tool exit side of each notched specimen, in accordance with Appendix X1. Adjust the notching machine
as required. The specimens used to determine notching conditions shall not be used to make determinations of impact resistance.
8.1 Notch Dimensions—The included angle of the notch shall be 45 6 1° with a radius of curvature at the apex of 0.25 6 0.05
mm (0.010 6 0.002 in.). The plane bisecting the notch angle shall be perpendicular to the face of the test specimen within 2°.
8.1.1 The notch is a critical factor of this test. It is extremely important, therefore, that dimensions of the notch in the specimen
are verified. There is evidence that the contour of notches cut in materials of widely differing physical properties by the same cutter
will differ. It is sometimes necessary to alter the cutter dimensions in order to produce the required notch contour for certain
materials.
8.1.2 A notching operation notches one or more specimens plus the “dummy bars”. The specimenExamine the notch produced
on the specimen by each cutter will be examined after every 500 notching operations or less frequently if experience shows this
to be acceptable. The specimen used to verify the notch shall be the same material that is being prepared for testing. Inspect and
verify the notch in the specimen. If the angle or radius of the notch does not meet the requirements of 8.1, the cutter shall be
replaced. One procedure for inspecting and verifying the notch is provided in Appendix X1.
NOTE 9—The contour of the notch made using multi-tooth cutters is checked by measuring the contour of the notch on a strip of soft metal that is
inserted between two specimens during the notching process.
NOTE 10—When the same material is being tested on a repetitive basis, and it is demonstrated that the notch in the specimen takes the contour of the
tip of the cutter and that the notch meets the contour requirements when checked in accordance with Appendix X1, then it is acceptable to check the
contour of the tip of the cutter instead of the notch in the specimen.
D6110 − 18
8.2 Notch Depth—The depth of the plastic material remaining in the specimen under the notch shall be 10.16 6 0.05 mm (0.400
6 0.002 in.). This dimension shall be measured with apparatus in accordance with 6.3. The tapered blade will be fitted to the notch.
The specimen will be approximately vertical between the anvils. Position the edge of the non-cavity (wider edge) surface centered
on the micrometer’s flat circular anvil.
8.3 Cutter Speed and Feed Rate—Select the cutter speed and feed speed based on the material being tested. The quality of the
notch will be adversely affected by thermal deformations and stresses induced during the cutting operation if proper conditions are
not selected. The notching parameters used shall not alter the physical state of the material, such as by raising the temperature
of a thermoplastic above its glass transition temperature.
8.3.1 In general, high cutter speeds, slow feed rates, and lack of coolant induce more thermal damage than a slow cutter speed,
fast feed speed, and the use of a coolant. Too high a feed speed/cutter speed ratio, however, has been shown to cause impacting
and cracking of the specimen. The range of cutter speed/feed ratios possible to produce acceptable notches has been shown to be
extended by the use of a suitable coolant.
8.3.1.1 For some thermoplastics, suitable notches have been produced using cutter speeds from 54 to 150 m/min and a feed rate
of 89 to 160 mm/min without a water coolant. Satisfactory notches also have been produced using the same cutter speeds at feed
speeds of from 36 to 160 mm/min with water coolant.
8.3.1.2 Embedded thermocouples have been used to determine the temperature rise in the material near the apex of the notch
during machining. Thermal stresses induced during the notching operation have been observed in transparent materials by viewing
the specimen at low magnification between crossed polars in monochromatic light. The specimens used to determine temperature
rise shall not be used to make determinations of impact resistance.
8.3.2 The feed rate and the cutter speed shall remain constant throughout the notching operation.
8.4 It is acceptable to notch specimens individually or in a group. In either case, however, an unnotched backup or dummy bar
shall be placed behind the last specimen in the sample holder to prevent distortion and chipping by the cutter as it exits from the
last test specimen.
8.5 All specimens having one dimension less than 12.7 mm (0.500 in.) shall have the notch cut on the shorter side. Compression
molded specimens shall be notched on the side parallel to the direction of application of molding pressure. The impact resistance
of a plastic material will be different if the notch is perpendicular to rather than parallel to the direction of molding, as with or
across the grain of an anisotropic bar cut from a plate.
9. Conditioning
9.1 Check the materials specification for the material that is being tested. If there are no conditioning requirements stated by
the materials specification, the test specimens shall be conditioned at 23 6 2°C (73 6 3.6°F) and 50 6 10 % relative humidity
for not less than 40 h after notching and prior to testing in accordance with Procedure A of Practice D618 unless documented
(between supplier and customer) that shorter conditioning time is sufficient for a given material to reach equilibrium of impact
resistance.
9.2 For hygroscopic materials, such as nylons, the material specifications (for example, Classification System D4066) call for
testing dry-as-molded specimens. Such requirements take precedence over the above routine preconditioning to 50 % relative
humidity. These specimens shall be sealed in water vapor-impermeable containers as soon as molded. When notching these
specimens, minimize the exposure time during notching and return the specimens to a dry container after notching to allow for
full cooling of the specimens prior to testing.
9.3 Test Conditions—Conduct tests in the standard laboratory atmosphere of 23 6 2°C (73 6 3.6°F) and 50 6 10 % relative
humidity, unless otherwise specified. In cases of disagreement, the tolerances shall be 61°C and 65 % relative humidity.
10. Procedure
10.1 Specimen Preparation:
10.1.1 Prepare the test specimens in accordance with the procedures in Section 7. At least five and preferably ten or more
individual determinations of impact resistance shall be made to determine the average impact resistance for a particular sample.
The specimens shall be of nominal width only.
10.1.2 Notch the specimens in accordance with the procedure in Section 8.
10.1.3 Condition the specimens in accordance with the materials specification for the material that is being tested. If there are
no conditioning requirements detailed in the materials specification, follow the conditioning requirements in Section 9.
10.2 Machine Preparation:
10.2.1 Estimate the breaking energy for the sample and select a pendulum of suitable energy. Select the lightest standard
pendulum that is expected to break all specimens in the group with an energy loss of not more than 85 % of its capacity (see 6.1).
Supporting data have been filed at ASTM International Headquarters and may
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