ASTM D5420-10

Standard Test Method for Impact Resistance of Flat, Rigid Plastic Specimen by Means of a Striker Impacted by a Falling Weight (Gardner Impact)

SIGNIFICANCE AND USE
Plastics are viscoelastic it is and therefore possible that they are sensitive to changes in velocity of weights falling on their surfaces. However, the velocity of a free-falling object is a function of the square root of the drop height. A change of a factor of two in the drop height will cause a change of only 1.4 in velocity. Hagan, et al (2) found that the mean-failure energy of sheeting was constant at drop heights between 0.30 and 1.4 m. Different materials respond differently to changes in the velocity of impact.
The test conditions used in Geometry GA are the same as those used in Geometry FA of Test Method D5628 (see Table 1).
The test conditions of Geometry GB are equivalent to the geometry used for the Gardner Variable Height Impact Test (3).
The test conditions of Geometry GC cause a punch-shear type of failure because the support-plate hole is close to the diameter of the striker.
The test conditions of Geometry GD are the same as those in Test Method D3763.
The test conditions of Geometry GE are the same as those in Test Method D4226, impactor head configuration H.25.
Because of the nature of impact testing, the selection of a test method and striker must be somewhat arbitrary. Consider the end use environment and requirements when choosing from the available striker geometries. However, the selection of any one of the striker geometries is permitted, after such consideration.
Note 2—Material processing can have a significant affect on the development of a plastic's physical properties. Consult relevant material standards for processing guidelines
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 striker impacted by a falling weight.
1.2 The values stated in SI units are to be regarded as the standard. The values given 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.
Note 1—There is no similar or equivalent ISO standard.

General Information

• Status: Historical
• Publication Date: 30-Jun-2010
• ICS: 83.140.10 - Films and sheets
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.10 - Mechanical Properties

Relations

• Replaces: ASTM D5420-04 - Standard Test Method for Impact Resistance of Flat, Rigid Plastic Specimen by Means of a Striker Impacted by a Falling Weight (Gardner Impact)
• Effective Date: 01-Jul-2010
• Referred By: ASTM F790-23 - Standard Guide for Testing Materials for Aerospace Plastic Transparent Enclosures
• Effective Date: 01-Jul-2010
• Referred By: ASTM D4101-17e1 - Standard Classification System and Basis for Specification for Polypropylene Injection and Extrusion Materials
• Effective Date: 01-Jul-2010
• Referred By: ASTM D8161-17(2022) - Standard Test Method for Impact Resistance of Thermoplastic Pavement Marking Materials over a Highway Substrate by Means of a Striker Impacted by a Falling Weight
• Effective Date: 01-Jul-2010
• Referred By: ASTM C1629/C1629M-23 - Standard Classification for Abuse-Resistant Nondecorated Interior Gypsum Panel Products and Fiber-Reinforced Cement Panels
• Effective Date: 01-Jul-2010
• Referred By: ASTM D4000-23 - Standard Classification System for Specifying Plastic Materials
• Effective Date: 01-Jul-2010
• Referred By: ASTM D7745-19 - Standard Practice for Testing Pultruded Composites
• Effective Date: 01-Jul-2010

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
Designation: D5420 − 10
StandardTest Method for
Impact Resistance of Flat, Rigid Plastic Specimen by Means
1
of a Striker Impacted by a Falling Weight (Gardner Impact)
This standard is issued under the fixed designation D5420; 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* D5947Test Methods for Physical Dimensions of Solid
Plastics Specimens
1.1 Thistestmethodcoversthedeterminationoftherelative
E171Practice for Conditioning and Testing Flexible Barrier
ranking of materials according to the energy required to crack
Packaging
or break flat, rigid plastic specimens under various specified
E691Practice for Conducting an Interlaboratory Study to
conditions of impact of a striker impacted by a falling weight.
Determine the Precision of a Test Method
1.2 The values stated in SI units are to be regarded as the
standard. The values given in parentheses are for information
3. Terminology
only.
3.1 Definitions—For definitions of plastics terms used in
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the this test method, see Terminologies D883 and D1600.
responsibility of the user of this standard to establish appro-
3.2 Definitions of Terms Specific to This Standard:
priate safety and health practices and determine the applica-
3.2.1 failure (of test specimen)—the presence of any crack
bility of regulatory limitations prior to use.
or split created by the impact of the falling weight that can be
NOTE 1—There is no similar or equivalent ISO standard.
seen by the naked eye under normal laboratory lighting
conditions.
2. Referenced Documents
3.2.1.1 Discussion—Failure shall include the following:
2
2.1 ASTM Standards:
(1) complete shattering of the plaque; (2) any crack radiating
D618Practice for Conditioning Plastics for Testing
out toward the edges of the plaque on either surface of the
D883Terminology Relating to Plastics
plaque; (3) any radial crack within or just outside the impact
D1600TerminologyforAbbreviatedTermsRelatingtoPlas-
area of the striker; (4) any hole in the plaque, whether due to
tics
brittle or ductile puncture, where unobstructed light or water
D2794Test Method for Resistance of Organic Coatings to
could pass through; (5) any brittle splitting of the bottom
the Effects of Rapid Deformation (Impact)
surface of the plaque; and (6) any glassy-type chip dislodged
D3763Test Method for High Speed Puncture Properties of
from or loosened from the plaque.
Plastics Using Load and Displacement Sensors
3.2.1.2 Discussion—Since the interpretation of failure may
D4066Classification System for Nylon Injection and Extru-
be slightly different between material types, refer to the
sion Materials (PA)
appropriate material specification for guidance.
D4226Test Methods for Impact Resistance of Rigid Poly-
(Vinyl Chloride) (PVC) Building Products
3.2.1.3 Discussion—Cracks usually start at the surface op-
D5628Test Method for Impact Resistance of Flat, Rigid
posite the one that is struck. For example, in some cases
Plastic Specimens by Means of a Falling Dart (Tup or
incipient cracking in glass-reinforced polymers is difficult to
Falling Mass)
differentiate from the reinforcing fibers. In such cases, apply a
penetratingdyesuchasgentianviolettothestressedsurfaceto
determine the onset of crack formation.
1
ThistestmethodisunderthejurisdictionofASTMCommitteeD20onPlastics
3.2.2 mean-failure energy (mean impact resistance)—the
and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.
CurrenteditionapprovedJuly1,2010.PublishedJuly2010.Originallyapproved
energy required to produce 50% failures, equal to the product
in 1993. Last previous edition approved in 2004 as D5420-04. DOI: 10.1520/
of the constant mass and mean failure height.
D5420-10.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3.2.3 mean-failure height (impact-failure height)—the
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
height at which a standard mass, when dropped on test
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. specimens, will cause 50% failures.
*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
1

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D5420 − 10
in velocity. Hagan, et al (2) found that the mean-failure energy
of sheeting was constant at drop heights between 0.30 and 1.4
m. Different materials respond diff
...

This document is not anASTM standard and is intended only to provide the user of anASTM 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:D5420–04 Designation: D5420 – 10
Standard Test Method for
Impact Resistance of Flat, Rigid Plastic Specimen by Means
1
of a Striker Impacted by a Falling Weight (Gardner Impact)
This standard is issued under the fixed designation D5420; 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*
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 striker impacted by a falling weight.
1.2 ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninbracketsparenthesesareforinformation
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.
NOTE 1—There is no similar or equivalent ISO standard.
2. Referenced Documents
2
2.1 ASTM Standards:
D618 Practice for Conditioning Plastics for Testing
D883 Terminology Relating to Plastics
D1600 Terminology for Abbreviated Terms Relating to Plastics
D2794 Test Method for Resistance of Organic Coatings to the Effects of Rapid Deformation (Impact)
D3763 Test Method for High Speed Puncture Properties of Plastics Using Load and Displacement Sensors
D4066 Classification System for Nylon Injection and Extrusion Materials (PA)
D4226 Test Methods for Impact Resistance of Rigid Poly(Vinyl Chloride) (PVC) Building Products
D5628 Test Method for Impact Resistance of Flat, Rigid Plastic Specimens by Means of a Falling Dart (Tup or Falling Mass)
D5947 Test Methods for Physical Dimensions of Solid Plastics Specimens
E171 Specification for Atmospheres for Conditioning and Testing Flexible Barrier Materials
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions—For definitions of plastics terms used in this test method, see Terminologies D883 and D1600.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 failure (of test specimen)—the presence of any crack or split created by the impact of the falling weight that can be seen
by the naked eye under normal laboratory lighting conditions.
3.2.1.1 Discussion—Failure shall include the following: ( 1) complete shattering of the plaque; (2) any crack radiating out
toward the edges of the plaque on either surface of the plaque; (3) any radial crack within or just outside the impact area of the
striker;(4) anyholeintheplaque,whetherduetobrittleorductilepuncture,whereunobstructedlightorwatercouldpassthrough;
(5) any brittle splitting of the bottom surface of the plaque; and (6) any glassy-type chip dislodged from or loosened from the
plaque.
3.2.1.2 Discussion—Since the interpretation of failure may be slightly different between material types, refer to the appropriate
material specification for guidance.
3.2.1.3 Discussion—Cracks usually start at the surface opposite the one that is struck. For example, in some cases incipient
cracking in glass-reinforced polymers is difficult to differentiate from the reinforcing fibers. In such cases, apply a penetrating dye
such as gentian violet to the stressed surface to determine the onset of crack formation.
1
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 Feb.July 1, 2004.2010. Published March 2004.July 2010. Originally approved in 1993. Last previous edition approved in 19982004 as
D5420-98.D5420-04. DOI: 10.1520/D5420-104.
2
ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,[e-mail] Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*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.
1

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D5420 – 10
3.2.2 mean-failure energy (mean impact resistance)—the energy required to produce 50% failures, equal to the product
...