1、Designation: D1004 09D1004 13Standard Test Method forTear Resistance (Graves Tear) of Plastic Film and Sheeting1This standard is issued under the fixed designation D1004; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method2 covers the determi
3、nation of the tear resistance of flexible plastic film and sheeting at very low rates ofloading, 51 mm (2 in.)/min. and is designed to measure the force to initiate tearing. The specimen geometry of this test methodproduces a stress concentration in a small area of the specimen. The maximum stress,
4、usually found near the onset of tearing, isrecorded as the tear resistance in newtons (or pounds-force).The method is not applicable for film or sheeting material where brittlefailures occur during testing or where maximum extension is greater than 101.6 mm (4 in.).1.1.1 Although resistance to tear
5、can be expressed in newtons per microns, (pounds-force per mil) of specimen thickness, thisis only advisable where correlation for the particular material being tested has been established. In most cases, comparison betweenfilms of dissimilar thickness is not valid.NOTE 1Film has been arbitrarily de
6、fined as sheeting having nominal thickness not greater than 0.25 mm (0.010 in.).1.2 Constant-Rate-of-Grip Separation TestThis test method employs a constant rate of separation of the grips holding the testspecimen.1.2.1 Specimen extension may be measured in this test method by grip separation.1.3 Th
7、e values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for informationonly.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establis
8、h appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.NOTE 2There is no similar or equivalent ISO known ISO equivalent to this standard.2. Referenced Documents2.1 ASTM Standards:3D618 Practice for Conditioning Plastics for TestingD882 Test Me
9、thod for Tensile Properties of Thin Plastic SheetingD883 Terminology Relating to PlasticsD4000 Classification System for Specifying Plastic MaterialsD5947 Test Methods for Physical Dimensions of Solid Plastics SpecimensD6988 Guide for Determination of Thickness of Plastic Film Test SpecimensE4 Pract
10、ices for Force Verification of Testing MachinesE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method2.2 ASTM Adjuncts:Die Drawings41 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommitt
11、ee D20.19 on Film, Sheeting, and MoldedProducts.Current edition approved May 1, 2009April 1, 2013. Published June 2009April 2013. Originally approved in 1949. Last previous edition approved in 20072009 asD1004 07.D1004 09. DOI: 10.1520/D1004-09.10.1520/D1004-13.2 The following reference may be of in
12、terest in connection with this test method: Graves, F. L., “The Evaluation ofTear Resistance in Elastomers,” India Rubber World, Vol111, No. 3, December 1944, pp. 305308.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annua
13、l Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from ASTM International Headquarters. Order Adjunct No. ADJD1004.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication o
14、f what changes have been made to the previous version. Becauseit 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 versionof the standard as published by ASTM is to be considere
15、d the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 Definitions:Definitions of terms applying to this test method appear in Termino
16、logy D883.4. Summary of Test Method4.1 The force to initiate tearing across a specific geometry of a film or sheeting specimen is measured using aconstant-rate-of-grip separation machine. The force necessary to initiate the tear is calculated from the load-time orload-displacement data.5. Significan
17、ce and Use5.1 Tear resistance of plastic film or sheeting is a complex function of its ultimate resistance to rupture. The specimen geometryand speed of testing in this test method are controlled to produce tearing in a small area of stress concentration at rates far belowthose usually encountered i
18、n service. Experience has shown the test to have its best reliability for materials which do not havebrittle failure or do not elongate greater than two hundred percent during testing.5.2 The data from this test method furnish comparative information for ranking the tearing resistance of plastic spe
19、cimens ofsimilar composition. Actual use performance in tearing of some plastics may not necessarily correlate with data from this testmethod.5.3 The resistance to tear of plastic film and sheeting, while partly dependent upon thickness, has no simple correlation withspecimen thickness. Hence, teari
20、ng forces measured in newtons (or pounds-force) cannot be normalized over a wide range ofspecimen thickness without producing misleading data as to the actual tearing resistance of the material. Data from this test methodare comparable only from specimens, which vary by no more than 610 % from the n
21、ominal or average thickness of all specimenstested. Therefore, the tearing resistance is expressed in maximum newtons (or pounds-force) of force to tear the specimen.5.4 The tear resistance of plastic film may be a specification that requires the use of this test method, but with some proceduralmodi
22、fications that take precedence when adhering to the specification. Therefore, it is advisable to refer to that materialspecification before using this test method. Table 1 of Classification System D4000 lists the ASTM materials standards thatcurrently exist.6. Apparatus6.1 Testing MachineA testing m
23、achine of the constant rate-of crosshead-movement type and comprising essentially thefollowing:6.1.1 Fixed MemberA fixed or essentially stationary member carrying one grip.6.1.2 Movable MemberA movable member carrying a second grip.6.1.3 GripsPreferably, a set of self-aligning grips for holding the
24、test specimen between the fixed member and the movablemember of the testing machine. The grips should minimize both slippage and uneven stress distribution.6.1.3.1 Fixed grips are rigidly attached to the fixed and movable members of the testing machine. Fixed grips may be used ifextreme care is take
25、n to ensure that the test specimen is inserted and clamped so that the long axis of the test specimen coincideswith the direction of pull through the center line of the grip assembly.6.1.3.2 Self-aligning grips are attached to the fixed and movable member of the testing machine in such a manner that
26、 they willmove freely into alignment as soon as any load is applied so that the long axis of the test specimen will coincide with the directionof the applied pull through the center line of the grip assembly.NOTE 3The specimens should be aligned as perfectly as possible with the direction of pull so
27、 that no rotary motion that may induce slippage willoccur in the grips; there is a limit to the amount of misalignment self-aligning grips will accommodate.NOTE 4Grips lined with thin rubber have been used successfully. Grips may be of the self-tightening type. In cases where specimens frequently fa
28、ilat the edge of the grips, the radius of curvature of the edges of the grips may be increased slightly at the point where they come in contact with thespecimen.6.1.4 Drive MechanismA drive mechanism capable of separating the movable member (grip) from the stationary member(grip) at a controlled vel
29、ocity of 51 mm (2 in.) 6 5 %/min.6.1.5 Load IndicatorA suitable load-indicating mechanism capable of showing the total tensile load carried by the testspecimen held by the grips. The testing machine shall be essentially free from inertial lag at the specified rate of testing and shallindicate the lo
30、ad with an accuracy of 61 %. The accuracy of the testing machine shall be verified in accordance with PracticesE4.6.1.6 Crosshead Extension IndicatorA suitable extension-indicating mechanism capable of showing the amount of change inthe separation of the grips (crosshead movement).6.2 ThicknessMeasu
31、re the specimen thickness in accordance with Test Methods D5947 or Guide D6988 as appropriate.6.3 Die4A die having the dimensions shown in Fig. 1 shall be used to cut all specimens. The 90 angle shall be honed sharpwith no radius or have a minimum practical radius. The cutting edge of the die shall
32、have a 5 negative rake, and shall be keptD1004 132sharp and free from nicks to avoid leaving ragged edges on the specimen. Wetting the surface of the sample and the cutting edgesof the die with water may facilitate cutting. The sample shall rest on the smooth, slightly yielding surface that will not
33、 damagethe die blade. Lightweight cardboard or a piece of leather belting is suitable. Care should be taken that the cut edges of thespecimen are perpendicular to its other surfaces and that the edges have a minimum of concavity.7. Test Specimens7.1 The test specimens shall be cut out with a die con
34、forming to the dimensions shown in Fig. 1 and shall not vary by morethan 0.5 % from these dimensions. The cutting edges of the die shall be kept sharp and free of all nicks to avoid leaving raggededges on the specimens.NOTE 5Caution should be used to ensure all samples are the same dimension if mult
35、iple specimens are cut at one time by stacking (layering) film.7.2 Machine direction specimens are cut perpendicular to the machine direction and transverse direction specimens are cutperpendicular to the transverse direction.7.3 At least ten specimens shall be tested for each sample, in the case of
36、 isotropic materials.7.4 Test a minimum of ten specimens each in the machine direction and in the transverse direction for each anisotropic testsample.7.5 Data from specimens which break at some obvious flaw or which break in or at the edges of the grips shall be discardedand additional specimens te
37、sted, unless such failures constitute a variable whose effect is being studied.7.6 Data from specimens which deviate markedly from the mean value of all tests shall be rejected if the deviation of thedoubtful value is more than five times the standard deviation from the mean value obtained by exclud
38、ing the doubtful results.NOTE 6For certain materials whose properties vary considerably throughout the film or sheeting, as many as 50 specimens cut from random portionsof the sheet must be tested if reliable tear resistance data are desired.8. Conditioning8.1 ConditioningCondition the test specimen
39、s at 23 6 2C (73.4 6 3.6F) and 50 6 5 % 10 % relative humidity for not lessthan 40 h prior to test in accordance with Procedure A of Practice D618, for those tests where conditioning is required. In casesof disagreement, the tolerances shall be 61C (61.8F) and 62 %65 % relative humidity.8.2 Test Con
40、ditionsConduct tests in the standard laboratory atmosphere of 23 6 2C (73.4 6 3.6F) and 50 6 5 % 10 %relative humidity, unless otherwise specified in the applicable ASTM material specification. In cases of disagreements, thetolerances shall be 61C (61.8F) and 62 %65 % relative humidity.9. Procedure9
41、.1 An initial jaw separation of 25.4 mm (1 in.) shall be used. The rate of travel of the power activated grip shall be 51-mm(2-in.)/min.NOTE 7In this test method, resistance to tear is calculated from the maximum load recorded. In testing most plastics, this maximum load is generatedat the onset of
42、tearing across the 13-mm (0.5-in.) testing width of the specimen.Tolerance 0.5Table of Metric Equivalentsin. mm4.0 101.600.750 19.051.061 26.951.000 25.401.118 28.402.0 50.800.002 0.0510.500 12.70FIG. 1 Die for Tear Test SpecimenD1004 1339.2 Measure the thickness of the specimen at several points in
43、 the notched area to the accuracy limits of the measuring devicesspecified in 6.2. Record the average thickness in microns (mil).9.3 Place the specimen in the grips of the testing machine so that the long axis of the enlarged ends of the specimen is in linewith the center line of the grip assembly.9
44、.4 After complete rupture of the specimen, the maximum tearing load in newtons (pounds-force), and the maximum extensionin mm (in.) shall be recorded.10. Calculation10.1 Calculate the mean maximum resistance to tearing, and the maximum extension for all specimens tested in each principaldirection of
45、 orientation. Record maximum tear resistance expressed in newtons (pounds-force) to three significant figures andmaximum extension expressed in mm (in.) to two significant figures.NOTE 8Resistance to tear may be expressed in newtons per microns, (pounds-force per mil) of specimen thickness where cor
46、relation for the particularmaterial being tested has been established. However, it should be realized that comparison between films of dissimilar thickness may not be valid.10.2 Calculate standard deviation.11. Report11.1 Report the following information:11.1.1 Complete identification of the materia
47、l tested, including type, source, manufacturers code number, form, principaldimensions, previous history, and orientation of sample with respect to anisotropy, if any.11.1.2 Average thickness of each test specimen and average thickness of all test specimens.11.1.3 Type of testing machine used.11.1.4
48、 Number of specimens tested in each principal direction.11.1.5 Average value of tear resistance calculated in newtons (pounds-force) and the maximum extension in mm (in.).11.1.6 Standard deviation from the averaged values obtained for specimens tested in each principal direction.12. Precision and Bi
49、as512.1 Table 1 and Table 2 are based on a round robin conducted between 1986 and 1990 in accordance with Practice E691,involving seven materials tested by seven laboratories. For each material, all the samples were prepared at one source, andrandomized sections of film were sent to each of the laboratories which prepared the test specimens and tested them. Each “testresult” was the average of ten determinations. Each laboratory obtained two test results for each material.12.2 Concept of r and RWarningThe following explanations of r and R (
