Standard Test Method for Impact Resistance of Flat, Rigid Plastic Specimens by Means of a Falling Dart (Tup or Falling Mass)

SCOPE
1.1 This test method covers the determination of the relative ranking of materials according to the energy required to crack or break flat, rigid plastic specimens under various specified conditions of impact of a free-falling dart (tup).  
1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.  
1.3  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 and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 8.  
Note 1—This test method and ISO 6603-1-1985 are technically equivalent only when the test conditions and specimen geometry required for Geometry FE and the Bruceton Staircase method of calculation are used.

General Information

Status
Historical
Publication Date
09-Mar-1996
Technical Committee
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM D5628-96(2001)e1 - Standard Test Method for Impact Resistance of Flat, Rigid Plastic Specimens by Means of a Falling Dart (Tup or Falling Mass)
English language
10 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)


NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
e1
Designation: D 5628 – 96 (Reapproved 2001)
Standard Test Method for
Impact Resistance of Flat, Rigid Plastic Specimens by
Means of a Falling Dart (Tup or Falling Mass)
This standard is issued under the fixed designation D5628; 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 (e) indicates an editorial change since the last revision or reapproval.
e NOTE—Editorial changes were made throughout in November 2001.
1. Scope Tup Falling Weight
D3763 Test Method for High-Speed Puncture Properties of
1.1 Thistestmethodcoversthedeterminationoftherelative
Plastics Using Load and Displacement Sensors
ranking of materials according to the energy required to crack
D4066 Classification System for Nylon Injection and
or break flat, rigid plastic specimens under various specified
Extrusion Materials PA
conditions of impact of a free-falling dart (tup).
E177 Practice for Use of the Terms Precision and Bias in
1.2 The values stated in SI units are to be regarded as the
ASTM Test Methods
standard. The values in parentheses are for information only.
E691 Practice for Conducting an Interlaboratory Study to
1.3 This standard does not purport to address all of the
Determine the Precision of a Test Method
safety concerns, if any, associated with its use. It is the
2.2 ISO Standards:
responsibility of the user of this standard to establish appro-
ISO 291 Standard Atmospheres for Conditioning and Test-
priate safety and health practices and determine the applica-
ing
bility of regulatory limitations prior to use. Specific hazard
ISO 6603-1 Plastics-Determination of Multiaxial Impact
statements are given in Section 8.
Behavior of Rigid Plastics—Part 1: Falling Dart Method
NOTE 1—This test method and ISO 6603-1-1985 are technically
equivalent only when the test conditions and specimen geometry required
3. Terminology
for Geometry FE and the Bruceton Staircase method of calculation are
3.1 Definitions:
used.
3.1.1 For definitions of plastic terms used in this test
2. Referenced Documents method, see Terminologies D883 and D1600.
3.2 Definitions of Terms Specific to This Standard:
2.1 ASTM Standards:
3.2.1 failure (of test specimen)—the presence of any crack
D374 Test Methods for Thickness of Solid Electrical Insu-
2 or split, created by the impact of the falling tup, that can be
lation
seen by the naked eye under normal laboratory lighting
D618 Practice for Conditioning Plastics for Testing
2 conditions.
D883 Terminology Relating to Plastics
3.2.2 mean-failure energy (mean-impact resistance)—the
D1600 Terminology for Abbreviated Terms Relating to
2 energy required to produce 50% failures, equal to the product
Plastics
of the constant drop height and the mean-failure mass or the
D1709 Test Method for Impact Resistance of Plastic Film
2 product of the constant mass and mean-failure height.
by the Free Falling Dart Method
3.2.3 mean-failure height (impact-failure height)—the
D1898 Practice for Sampling of Plastics
height at which a standard mass, when dropped on test
D2444 Test Method for Determination of the Impact Re-
specimens, will cause 50% failures.
sistance of Thermoplastic Pipe and Fittings by Means of a
NOTE 2—Cracks usually start at the surface opposite the one that is
struck. Occasionally incipient cracking in glass-reinforced products, for
ThistestmethodisunderthejurisdictionofASTMCommitteeD20onPlastics
and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.
Current edition approved March 10, 1996. Published July 1996. Originally Annual Book of ASTM Standards, Vol 08.04.
published as D5628–94. Last previous edition D5628–95. Annual Book of ASTM Standards, Vol 08.02.
2 7
Annual Book of ASTM Standards, Vol 08.01. Annual Book of ASTM Standards, Vol 14.02.
3 8
Annual Book of ASTM Standards, Vol 10.01. Available from American National Standards Institute, 25 W. 43rd St., 4th
Discontinued; see 1998 Annual Book of ASTM Standards, Vol 08.01. Floor, New York, NY 10036.
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959, United States.
e1
D 5628 – 96 (2001)
example, may be difficult to differentiate from the reinforcing fibers. In
5.3.1 The conical configuration of the 12.7-mm diameter
such cases, a penetrating dye may be used to confirm the onset of crack
tup used in Geometry FB minimizes problems with tup
formation.
penetration and sticking in failed specimens of some ductile
3.2.4 mean-failure mass (impact-failure mass)—themassof
materials.
the dart (tup) that, when dropped on the test specimens from a
5.4 The test conditions of Geometry FC are the same as
standard height, will cause 50% failures.
those of Test Method A of Test Method D1709. They have
3.2.5 tup—a dart with a hemispherical nose. See 7.2 and
been used in specifications for extruded sheeting.Alimitation
Fig. 1.
of this geometry is that considerable material is required.
5.5 The test conditions of Geometry FD are the same as for
4. Summary of Test Method
Test Method D3763.
4.1 Afree-falling dart (tup) is allowed to strike a supported 5.6 The test conditions of Geometry FE are the same as for
ISO6603-1.
specimen directly. Either a dart having a fixed mass may be
dropped from various heights, or a dart having an adjustable 5.7 Because of the nature of impact testing, the selection of
mass may be dropped from a fixed height. (See Fig. 2). a test method and tup must be somewhat arbitrary. While any
4.2 The procedure determines the energy (mass 3height) one of the tup geometries may be selected, knowledge of the
that will cause 50% of the specimens tested to fail (mean final or intended end-use application should be considered.
failure energy).
5.8 Clamping of the test specimen will improve the preci-
4.3 The technique used to determine mean failure energy is sion of the data. Therefore, clamping is recommended. How-
commonly called the Bruceton Staircase Method or the Up-
ever, with rigid specimens, valid determinations can be made
and-DownMethod (1). Testingisconcentratednearthemean, withoutclamping.Unclampedspecimenstendtoexhibitsome-
reducing the number of specimens required to obtain a reason-
what greater impact resistance.
ably precise estimate of the impact resistance.
5.9 Before proceeding with this test method, reference
4.4 Eachtestmethodpermitstheuseofdifferenttupandtest
shouldbemadetothespecificationofthematerialbeingtested.
specimen geometries to obtain different modes of failure,
Any test specimens preparation, conditioning, dimensions, or
permit easier sampling, or test limited amounts of material.
testing parameters or combination thereof covered in the
There is no known means for correlating the results of tests
relevant ASTM materials specification shall take precedence
made by different impact methods or procedures.
over those mentioned in this test method. If there are no
relevantASTM material specifications, then the default condi-
5. Significance and Use
tions apply.
5.1 Plastics are viscoelastic and therefore may be sensitive
6. Interferences
to changes in velocity of the mass falling on their surfaces.
However, the velocity of a free-falling object is a function of
6.1 Falling-mass-impact-test results are dependent on the
the square root of the drop height.Achange of a factor of two
geometry of both the falling mass and the support. Thus,
in the drop height will cause a change of only 1.4 in velocity.
impact tests should be used only to obtain relative rankings of
Hagan et al (2) found that the mean-failure energy of sheeting
materials. Impact values cannot be considered absolute unless
was constant at drop heights between 0.30 and 1.4 m. This
the geometry of the test equipment and specimen conform to
suggests that a constant mass-variable height method will give
theend-userequirement.Dataobtainedbydifferentprocedures
the same results as the constant height-variable mass tech-
withinthistestmethod,orwithdifferentgeometries,cannot,in
nique. On the other hand, different materials respond differ-
general, be compared directly with each other. However, the
entlytochangesinthevelocityofimpact.Equivalenceofthese
relative ranking of materials may be expected to be the same
methods should not be taken for granted.While both constant-
betweentwotestmethodsifthemodeoffailureandtheimpact
mass and constant-height techniques are permitted by these
velocities are the same.
methods, the constant-height method should be used for those
6.1.1 Falling-mass-impact types of tests are not suitable for
materials that are found to be rate-sensitive in the range of
predicting the relative ranking of materials at impact velocities
velocities encountered in falling-weight types of impact tests.
differing greatly from those imposed by these test methods.
5.2 The test geometry FA causes a moderate level of stress
6.2 As cracks usually start at the surface opposite the one
concentration and can be used for most plastics.
that is struck, the results can be greatly influenced by the
5.3 Geometry FB causes a greater stress concentration and
quality of the surface of test specimens. Therefore, the com-
results in failure of tough or thick specimens that do not fail
position of this surface layer, its smoothness or texture, levels
with Geometry FA (3). This approach may produce a punch
ofandtypeoftexture,andthedegreeoforientationintroduced
shear failure on thick sheet. If that type of failure is undesir-
during the formation of the specimen (such as may occur
able, Geometry FC may be used. Geometry FB is suitable for
during injection molding) are very important variables. Flaws
research and development because of the smaller test area
in this surface will also affect results.
required.
6.3 Impact properties of plastic materials can be very
sensitive to temperature. This test can be carried out at any
reasonable temperature and humidity, thus representing actual
use environments. However, this test method is intended
The boldface numbers in parentheses refer to a list of references at the end of
the text. primarily for rating materials under specific impact conditions.
e1
D 5628 – 96 (2001)
Dimensions of Conical Dart (Not to scale.)—Fig. 1(b)
NOTE 1—Unless specified, the tolerance on all dimensions shall be 62%.
Position Dimension, mm Dimension, in.
A 27.2 1.07
B 15 0.59
C 12.2 0.48
D 6.4 0.25
E 25.4 1
F 12.7 0.5
R 6.35 6 0.05 0.250 6 0.002
(nose radius)
r (radius) 0.8 0.03
A
S (diameter) 6.4 0.25
u 25 6 1° 25 6 1°
A
Larger diameter shafts may be used.
FIG. 1 Tup Geometries for Geometries FA (1a), FB (1b), FC (1c), FD (1d), and FE (1e)
e1
D 5628 – 96 (2001)
FIG. 2 One Type of Falling Mass Impact Tester
7. Apparatus 7.1.2 Tup Support, capable of supporting a 13.5-kg (30-lb)
mass, with a release mechanism and a centering device to
7.1 Testing Machine—The apparatus shall be constructed
ensure uniform, reproducible drops.
essentiallyasisshowninFig.2.Thegeometryofthespecimen
NOTE 3—Reproducible drops may be ensured through the use of a tube
clamp and tup shall conform to the dimensions given in 7.1.1
or cage within which the tup falls. In this event, care should be exercised
and 7.2.
so that any friction that develops will not reduce the velocity of the tup
7.1.1 Specimen Clamp—For flat specimens, a two-piece
appreciably.
annular specimen clamp similar to that shown in Fig. 3 is
7.1.3 Positioning Device—Means shall be provided for
recommended.ForGeometriesFAandFD,theinsidediameter
positioning the tup so that the distance from the impinging
shouldbe76.0 63.0mm(3.00 60.12in.).ForGeometryFB,
surface of the tup head to the test specimen is as specified.
theinsidediametershouldbe38.1 60.80mm(1.5 60.03in.).
7.2 Tup:
For Geometry FC, the inside diameter should be 127.0 6 2.5
7.2.1 The tup used in Geometry FA shall have a 15.86 6
mm (5.00 6 0.10 in.). For Geometry FE an annular specimen
0.10-mm (0.625 6 0.004-in.) diameter hemispherical head of
clamp similar to that shown in Fig. 4 is required. The inside
tool steel hardened to 54 HRC or harder.Asteel shaft about 13
diametershouldbe40 62mm(1.57 60.08in.)(seeTable1).
mm (0.5 in.) in diameter shall be attached to the center of the
For Geometries FA, FB, FC, and FD, the inside edge of the
flat surface of the head with its longitudinal axis at 90° to that
upper or supporting surface of the lower clamp should be
surface. The length of the shaft shall be great enough to
rounded slightly; a radius of 0.8 mm (0.03 in.) has been found
accommodate the maximum mass required (see Fig. 1(a) and
tobesatisfactory.ForGeometryFEthisradiusshouldbe1mm
Table 1).
(0.04 in.).
7.2.2 The tup used in Geometry FB shall be made of tool
7.1.1.1 Contoured specimens shall be firmly held in a jig so
steel hardened to 54 HRC or harder. The head shall have a
that the point of impact will be the same for each specimen. diameter of 12.76 0.1 mm (0.500 6 0.003 in.) with a conical
e1
D 5628 – 96 (2001)
FIG. 3 Support Plate/Specimen/Clamp Configuration for Geometries FA, FB, FC, and FD
FIG. 4 Test-Specimen Support for Geometry FE
TABLE 1 Tup and Support Ring Dimensions
axisat90°tothatsurface.Thelengthoftheshaftshallbegreat
Dimensions, mm (in.) enough to accommodate the maximum mass (see Fig. 1(c) and
Geometry
Table 1).
Tup Diameter Inside Diameter Support Ring
FA 15.86 6 0.10 76.0 6 3.0 7.2.4 The tup used in Geometry FD shall have a 12.70 6
(0.625 6 0.004) (3.00 6 0.12)
0.25-mm (0.500 6 0.010-in.) diameter hemispherical head of
FB 12.7 6 0.1 38.1 6 0.8
tool steel hardened to 54 HRC or harder.Asteel shaft about 8
(0.500 6 0.003) (1.5 6 0.03)
FC 38.1 6 0.4 127.0 6 2.5
mm (0.31 in.) in diameter shall be attached to the center of the
(1.5 6 0.010) (5.00 6 0.10)
flat surface of the head with its longitudinal axis at 90° to the
FD 12.70 6 0.25 76.0 6 3.0
surface. The length of the shaft shall be great enough to
(0.500 6 0.010) (3.00 6 0.12)
FE 20.0 6 0.2 40.0 6 2.0
accommodate the maximum mass required (see Fig. 1(d) and
(0.787 6 0.008) (1.57 6 0.08)
Table 1).
7.2.5 The tup used in Geometry FE shall have a 20.0 6
0.2-mm (0.787 6 0.008-in.) diameter hemispherical head of
tool steel hardened to 54 HRC or harder.Asteel shaft about 13
(50°includedangle)configurationsuchthattheconicalsurface
mm (0.5 in.) in diameter shall be attached to the center of the
is tangent to the hemispherical nose. A 6.4-mm (0.25-in.)
flat surface of the head with its longitudinal axis at 90° to the
diameter shaft is satisfactory (see Fig. 1(b) and Table 1).
surface. The length
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.