1、Designation: D 7192 08aStandard Test Method forHigh Speed Puncture Properties of Plastic Films Using Loadand Displacement Sensors1This standard is issued under the fixed designation D 7192; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of punctureproperties of plastic films, over a range of
3、test velocities.1.1.1 Test Method D 1004 has defined film as having athickness not greater than 0.25 mm (0.010 in.). Plastic mate-rials having a thickness above this limit are not to be excludedfrom use unless shown to be rigid (see 3.2.1). Test MethodD 3763 is the recommended method for instrumente
4、d puncturetesting of rigid plastics.1.2 Test data obtained by this test method is relevant andappropriate for use in engineering design.1.3 The values stated in SI units are to be regarded asstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its
5、 use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1This test method does not closely conform to ISO 7765-2.The only similarity between the two tests is that the
6、y are both instru-mented impact tests. The differences in striker, fixture, specimen geom-etries and in test velocity can produce significantly different test results.2. Referenced Documents2.1 ASTM Standards:2D 618 Practice for Conditioning Plastics for TestingD 883 Terminology Relating to Plastics
7、D 1004 Test Method for Tear Resistance (Graves Tear) ofPlastic Film and SheetingD 1600 Terminology for Abbreviated Terms Relating toPlasticsD 3763 Test Method for High Speed Puncture Properties ofPlastics Using Load and Displacement SensorsD 4000 Classification System for Specifying Plastic Mate-ria
8、lsD 6988 Guide for Determination of Thickness of PlasticFilm Test Specimens3. Terminology3.1 DefinitionsFor definitions see Terminology D 883 andfor abbreviations, see Terminology D 1600.3.2 Definitions of Terms Specific to This Standard:3.2.1 rigid, adjany plastic specimen that, when placed onthe s
9、upport component of the open clamp assembly, does notdeflect into the center of the unsupported region (under its ownweight) by more than 0.05 mm from the horizontal plane of thesupport component.3.2.1.1 DiscussionThis definition is provided as a guide-line to allow testing of soft, pliable plastic
10、materials that arethicker than 0.25 mm.4. Significance and Use4.1 This test method is designed to provide load versusdeformation response of plastic films under essentially multi-axial deformation conditions at impact velocities. This testmethod further provides a measure of the rate sensitivity of
11、theplastic films to impact.4.2 Multi-axial impact response, while partly dependent onthickness, does not necessarily have a linear correlation withspecimen thickness. Therefore, results should be comparedonly for specimens of essentially the same thickness, unlessspecific responses versus thickness
12、formulae have been estab-lished for the plastic films being tested.4.3 For many plastic films, there may be a specification thatrequires the use of this test method, but with some proceduralmodifications that take precedence when adhering to thespecification. Therefore, it is advisable to refer to t
13、hat material1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.Current edition approved Nov. 1, 2008. Published November 2008. Originallyapproved in 2005. Last previous edition approved in 2008
14、 as D 7192 - 08.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the
15、 end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.specification before using this test method. Table 1 of Classi-fication System D 4000 lists theASTM materials standards thatcurrently exist.4.4 The values obtained
16、by this test method are highlydependent on the method and conditions of film fabrication aswell as the type and grade of resin. Results can vary signifi-cantly, depending upon sample quality, uniformity of filmgage, die marks, contaminants, and so forth.5. Apparatus5.1 The testing machine shall cons
17、ist of two assemblies, onefixed and the other driven by a suitable method to achieve therequired impact velocity (that is, hydraulic, pneumatic, me-chanical, or gravity):5.1.1 Specimen Clamp AssemblyThis device shall bepermitted to be variable with respect to the holding of thespecimen material, dep
18、ending upon specimen characteristics.The unsupported region of the specimen clamp assembly shallhave a diameter of 76 6 3.0 mm. The edges of the unsupportedregion shall be rounded to a radius of 0.8 6 0.4 mm. Theholding technique employed on the specimen must not inter-fere with the radius edge of t
19、he clamp assembly. Specimensshould be held taut but not stretched so as to cause damage tothe specimen prior to test.NOTE 2The following techniques have been successfully employedfor different types of plastic films: Parallel rigid plates clamped together with sufficient force (mechani-cally, pneuma
20、tically or hydraulically) to prevent slippage of the specimenin the clamp during impact. Rubber-like gaskets or o-rings affixed to the rigid plates to providecushioning or gripping of the specimen when clamping force is applied. Removable assemblies, consisting of two concentric rings (one slightlyl
21、arger than the other, similar to an embroidery hoop) that, when assembledand clamped between two rigid plates, succeed in pulling the specimentaut over the specified unsupported region prior to testing.All of the abovetechniques must employ the specified unsupported region and edge radiusas noted in
22、 5.1.1.5.1.2 Plunger Assembly, consisting of a 12.70 6 0.13-mmdiameter rod with a hemispherical end of the same diameterpositioned perpendicular to, and centered on, the clamp hole.Plunger assembly shall be of sufficient length so as to allow forcomplete puncture of the test specimen. Plunger assemb
23、lymaterial shall be stainless steel, steel or aluminum. Surfacefinish of the plunger assembly shall be 16 in. 0.4 m.5.1.3 Other GeometriesThe dimensions given in 5.1.1and 5.1.2 shall be the standard geometry. If other plunger orhole sizes are used they shall be highlighted in the report.Correlations
24、 have not been established between differentplunger geometries, materials, and finishes.5.1.4 Load Sensing SystemA load cell of sufficiently highnatural resonance frequency, as described in A1.1, used to-gether with a calibrating network for adjusting load sensitivity.5.1.5 Plunger Displacement Meas
25、urement SystemAmeans of monitoring the displacement of the moving assemblyduring the loading and complete penetration of the specimen.This can be accomplished through the use of a suitabletransducer or potentiometer attached directly to the system.Photographic or optical systems can also be utilized
26、 formeasuring displacement.5.1.5.1 Alternatively, displacement shall be permitted to becalculated as a function of velocity and total available energyat initial impact, along with increments of load versus time,using a microprocessor.5.1.5.2 Some machines use an accelerometer, whose outputis used to
27、 calculate both load and displacement.5.1.6 Display and Recording InstrumentationUse anysuitable means to display and record the data developed fromthe load and displacement-sensing systems, provided its re-sponse characteristics are capable of presenting the datasensed, with minimal distortion. The
28、 recording apparatus shallrecord load and displacement simultaneously. For furtherinformation, see A1.2.5.1.6.1 The most rudimentary apparatus is a cathode-rayoscilloscope with a camera. This approach also requires aplanimeter or other suitable device, capable of measuring thearea under the recorded
29、 load-versus-displacement trace of theevent with an accuracy of 65%.5.1.6.2 More sophisticated systems are commercially avail-able. Most of them include computerized data reduction andautomatic printouts of results.5.2 Measuring Instrument, accurate to 0.0025 mm in thefilm thickness range defined in
30、 1.1.1 (see Guide D 6988).6. Test Specimen6.1 Specimens must be large enough to be adequatelygripped in the clamp. In general, the minimum lateral dimen-sion should be at least 13 mm greater than the diameter of thehole in the clamp or any clamping gaskets or o-rings incorpo-rated into the clamping
31、mechanism (see 5.1.1 and 9.9).6.2 Specimens shall be cut from plastic films produced byany suitable process.6.3 The specimens shall be free of pinholes, wrinkles, foldsor other obvious imperfection, unless such imperfectionsconstitute variables under study.7. Conditioning7.1 ConditioningCondition th
32、e test specimens at 23 62C (73.4 6 3.6F) and 50 6 10 % relative humidity for notless than 40 h prior to test in accordance with Procedure A ofPractice D 618 unless otherwise specified by agreement or therelevant ASTM material specification. In cases of disagree-ment, the tolerances shall be 61C (61.
33、8F) and 65%relative humidity.7.2 Test ConditionsFor standard testing, conduct the testsat 23 6 2C (73.4 6 3.6F) and 50 6 10 % relative humidityunless otherwise specified by agreement or the relevant ASTMmaterial specification. In cases of disagreement, the tolerancesshall be 61C (61.8F) and 65 % rel
34、ative humidity.7.2.1 By changing the conditioning and test temperature ina controlled manner for a given test velocity, the temperature atwhich transition from ductile to brittle failure occurs can bedetermined for most plastic films. If film properties at non-standard conditions are studied, the co
35、nditions used shall benoted in the report.8. Speed of Testing8.1 For recommended testing speeds, see 9.4.D 7192 08a29. Procedure9.1 Test a minimum of five specimens at each specifiedspeed.9.2 Measure and record the thickness of each specimen tothe nearest 0.0025 mm at the center of the specimen.9.3
36、Clamp the specimen between the plates of the specimenholder, taking care to center the specimen for uniform gripping.9.4 Set the test speed to the desired value. The testing speed(movable-member velocity at the instant before contact withthe specimen) shall be as follows:9.4.1 For single-speed tests
37、, use a velocity of 200 m/min.9.4.1.1 Other speeds are permissible, provided they areclearly stated in the report.9.4.2 To measure the dependence of puncture properties onimpact velocity, use a broad range of test speeds. Somesuggested speeds are 2.5, 25, 125, 200, and 250 m/min.9.5 Set the availabl
38、e energy so that the velocity slowdown isno more than 20 % from the beginning of the test to the pointof peak load. If the velocity should decrease by more than20 %, discard the results and make additional tests on newspecimens with more available energy.NOTE 3It is observed that when the available
39、energy is at least threetimes the absorbed energy at the peak load velocity slow-down is less than20 %.9.6 Make the necessary adjustments to data collectionapparatus as required by the manufacturers instructions orconsult literature such as STP 9363for further informationregarding setting up data ac
40、quisition systems.9.7 Conduct the test, following the manufacturers instruc-tions, for the specific equipment used.9.8 Remove the specimen and inspect the gripped portionfor striations or other evidence of slippage. If there is evidenceof slippage, modify the clamping conditions or increase thespeci
41、men size and repeat test procedures.9.9 Check plunger assembly for any film debris or residuebefore performing subsequent tests.10. Calculation10.1 Using the load-versus-displacement trace and appro-priate scaling factors, calculate the following:10.1.1 Peak load, in Newtons.10.1.2 Deflection, in mi
42、llimetres, to the point where peakload first occurred.10.1.3 From the area within the trace, calculate:10.1.3.1 Energy, in Joules, to the point where peak load firstoccurred.10.1.3.2 Total energy absorbed. The point for determiningthis has not been standardized. Therefore, the point used foreach tes
43、t must be stated in the report.10.1.4 Load, deflection, energy, or combination thereof, atany other specific point of interest (see Appendix X1).10.2 For each series of tests, calculate the arithmetic meanfor each of the above, to three significant figures.10.3 Calculate the estimated standard devia
44、tions as follows:S 5 S(X22 nX2n 2 1D1/2 (1)where:S = estimated standard deviation,X = value of a single determination,n = number of determinations, andX= arithmetic mean of the set of determinations.11. Report11.1 Report the following information:11.1.1 Complete identification of the material tested
45、, includ-ing type, source, manufacturers code number, form andprevious history,11.1.2 Specimen size and thickness,11.1.3 Method of preparing test specimens (extrusion mold-ing, blow molding, and so forth),11.1.4 Geometry of clamp and plunger, if different from5.1.1 and 5.1.2,11.1.5 Source and types
46、of equipment,11.1.6 Speed of testing (see 9.4),11.1.7 The point on the curve at which total energy wascalculated (see 10.1.3.2),11.1.8 Average value and standard deviation for each of theproperties listed in 10.1,11.1.9 Whether or not any slippage of the specimens wasdetected (see Note 3),11.1.10 If
47、 the effect of testing speeds was studied (see9.4.2),11.1.11 Type of plunger material used for the test, and11.1.12 Test specimen conditioning, if different from 7.1.NOTE 4When slippage or cutting of the test specimen occurs at ornear the edge of the support clamp, the result shall be considered inv
48、aliddue to the error in calculated energy absorption caused by the slipping orcutting of the specimen during the impact test. Alternate clampingtechniques, adhering to the requirements of 5.1.1, must be used to preventany slippage or cutting of the test specimen.12. Precision and Bias12.1 Precision
49、and Bias for this test method are currentlyunder investigation.13. Keywords13.1 falling weight; impact testing; plastic thin film; punc-ture properties3Instrumented Impact Testing of Plastics and Composite Materials, ASTM STP936, ASTM, 1986.D 7192 08a3ANNEX(Mandatory Information)A1. MINIMUM INSTRUMENTATION REQUIREMENTSA1.1 Force MeasurementAny transducer that meets theperformance requirements for dynamic force measurementshall be permitted to be used. This includes, but is not limitedto, strain gage force transducers, piezo-electric force transduc-
