1、Designation: D4964 96 (Reapproved 2012)Standard Test Method forTension and Elongation of Elastic Fabrics (Constant-Rate-of-Extension Type Tensile Testing Machine)1This standard is issued under the fixed designation D4964; the number immediately following the designation indicates the year oforiginal
2、 adoption or, in the case of revision, 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. Scope1.1 This test method covers the measurement of tension andelongation of
3、 wide or narrow elastic fabrics made from naturalor man-made elastomers, either alone or in combination withother textile yarns, when tested with a constant-rate-of-extension (CRE) type tensile testing machine.NOTE 1For determination of similar testing using the constant-rate-of-load (CRL) type tens
4、ile testing machine, refer to Test Method D1775.1.2 The use of this test method requires the selection of, ormutual agreement upon, loop tension(s) and elongation(s) atwhich the test results will be determined.1.3 Laundering procedures require mutual agreement on theselection of temperature and numb
5、er of washing cycles anddrying cycles to be used.1.4 The values stated in SI units or inch-pound units are tobe regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore each systemmust be used independently of the other, without combiningvalues in any
6、way.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its 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.2. Referenc
7、ed Documents2.1 ASTM Standards:2D76 Specification for Tensile Testing Machines for TextilesD123 Terminology Relating to TextilesD1775 Test Method for Tension and Elongation of WideElastic Fabrics3D1776 Practice for Conditioning and Testing TextilesD4850 Terminology Relating to Fabrics and Fabric Tes
8、tMethods3. Terminology3.1 For all terminology related to Subcommittee D13.59 onFabric Test Methods, General, see Terminology D4850.3.2 The following terms are relevant to this standard:constant-rate-of-extension tensile testing machine (CRE),constant-rate-or-load tensile testing machine (CRL), elast
9、icfabric, elongation, extension, extension-recovery cycle, force,loop tension, narrow elastic fabric, tension, tension-recoverychart, tension test, wide elastic fabric.3.3 For definitions of all other textile terms see TerminologyD123.4. Summary of Test Method4.1 Loop Tension at Specified Elongation
10、(s)A condi-tioned loop specimen is mounted in a CRE-type tensile testingmachine. The specimen is then extended at a specified rate toa specified loop tension, and returned at a specified rate to zerotension. The cycle is repeated two more times to give a total ofthree cycles. During the test, extens
11、ion-recovery curves may beplotted by an automatic recorder for all or only the third cycle.The tension at specified percent elongation(s) is calculatedfrom the graph of the third cycle or obtained from theinstrument.4.2 Elongation at Specified Loop TensionA conditionedloop specimen is mounted in a C
12、RE-type tensile testingmachine. The specimen is then loaded at a specified rate to aspecified loop tension, and unloaded at a specified rate to zeroloop tension. The cycle is repeated two more times to give atotal of three cycles. During the test, tension-recovery curvesmay be plotted by an automati
13、c recorder for all or only the thirdcycle. The elongation at a specified loop tension is calculatedfrom the graph of the third cycle or obtained from theinstrument.5. Significance and Use5.1 This test method for testing loop tension and elongationof elastic fabrics is considered satisfactory for acc
14、eptancetesting of commercial shipments of elastic fabrics because thetest method is used in the trade for acceptance testing.1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.59 on Fabric Test Methods,General.Current edi
15、tion approved July 1, 2012. Published August 2012. Originallyapproved in 1989. Last previous edition approved in 2008 as D4964 96(2008)2.DOI: 10.1520/D4964-96R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book
16、of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Uni
17、ted States.5.1.1 In case of a dispute arising from differences inreported test results when using this test method for acceptancetesting of commercial shipments, the parties should conductcomparative tests to determine if there is a statistical biasbetween their laboratories. Competent statistical a
18、ssistance isrecommended for the investigation of bias. As a minimum, thetwo parties should take a group of test specimens that are ashomogeneous as possible and that are from a lot of material ofthe type in question. The test specimens should then berandomly assigned in equal numbers to each laborat
19、ory fortesting. The average results from the two laboratories should becompared using students t-test for unpaired data and anacceptable probability level chosen by the two parties beforethe testing is begun. If bias is found, either its cause must befound and corrected or the purchaser and the supp
20、lier mustagree to interpret future test results with consideration to theknown bias.5.2 This test method specifies the use of the CRE-typetensile testing machine. Users of this test method are cautionedthat loop tension test data obtained using this method are notcomparable to tension test data obta
21、ined using Test MethodD1775 because of the differences in testing machines. TestMethod D1775 uses a CRL-type tensile testing machine.5.3 The loop tension and extension relationship of an elasticfabric is an important criterion for judging the suitability of thefabric for various end uses, such as: f
22、oundation garments,brassieres, and swimsuits.5.4 Data from loop tension-recovery curves can be com-pared only if the tension testing machine, rate-of-extension,maximum loading (or extension), and specimen specificationsare comparable. Since different machine set-ups will causedifferent results on th
23、e same fabric, machine set-ups mustalways be specified before making a test and be reported withthe test results.5.5 The test for measuring loop tension at specified elonga-tion(s) is used to determine the tension of an elastic fabricwhen subjected to a specified elongation which is less than theelo
24、ngation required to rupture the fabric. The test prescribespoints of measurement on the extending (outgoing) cycle only.5.6 The test for measuring elongation at specified tension(s)is used to determine the elongation of an elastic fabric whensubjected to a specified loop tension which is less than t
25、hetension required to rupture the fabric. The test prescribes pointsof measurement on the loading (outgoing) cycle only.6. Apparatus6.1 Tensile Testing Machine, CRE-Type,4conforming toSpecification D76, equipped with an automatic recordingdevice and cycling controls.6.2 Band Clamps, to hold loop spe
26、cimen during testing. Thediameter of the anvils will be 13.06 0.25 mm (0.5 6 0.01 in.)or 6.56 0.25 mm (0.25 6 0.01 in.). The length of the anvil willnot be less than 76 mm (3.0 in.).6.3 Sewing Machine Single-Needle.7. Sampling7.1 Lot SampleAs a lot sample for acceptance testing,take at random the nu
27、mber of rolls of fabric as directed in anapplicable material specification or other agreement betweenthe purchaser and the supplier. Consider rolls of fabric to be theprimary sampling units.NOTE 2An adequate specification or other agreement between thepurchaser and the supplier requires taking into
28、account the variabilitybetween rolls of fabric, and the variability between specimens from aswatch from a roll of fabric, to provide a sampling plan with a meaningfulproducers risk, consumers risk, acceptable quality level, and limitingquality level.7.2 Laboratory SampleAs a laboratory sample for ac
29、cep-tance testing, take a full width swatch,2m(2yd)long, fromthe end of each roll of fabric in the lot sample, after firstdiscarding a minimum of1m(1yd)offabric from the veryoutside of the roll.7.3 Test SpecimensTake test specimens as follows:7.3.1 Wide Elastic FabricsIf the purchaser and the sup-pl
30、ier agree to test the fabric in only one direction, cut fivespecimens from each swatch in the laboratory sample with thelong dimension of the specimens parallel to the direction oftest. If the purchaser and the supplier agree to test the fabric inboth directions, from each full-width swatch in the l
31、aboratorysample, cut five specimens parallel to the long dimension andfive specimens perpendicular to the long dimension. Speci-mens should be spaced along a diagonal to allow for represen-tation in each specimen of different warp and filling areas, orwale and course areas. Take no specimens nearer
32、than one tenthof the fabric width from the selvage.7.3.2 Narrow Elastic FabricCut five specimens fromeach swatch in the laboratory sample. For narrow knitted orwoven elastic fabrics that are more than 75 mm (3 in.) wide,the purchaser and the supplier may agree to (1) use specimensof the widths speci
33、fied in 8.1.1 for wide elastic fabrics ofcomparable construction, or (2) if wide clamps are available,use full-width specimens.8. Preparation of Test Specimens8.1 Cut specimens as directed below:8.1.1 Wide Elastic FabricCut specimens 350 by 100 mm(14 by 4 in.). Trim, or ravel woven fabrics by taking
34、 yarnsalternately from the two sides, to a width as near 75 6 2mm(3 6 0.05 in.), as possible. If fabrics are ravelled to obtain thespecimen width, specimens should contain the same number ofyarns in the testing direction.8.1.2 Narrow Elastic FabricCut specimens with the350-mm (14-in.) dimension para
35、llel to the length of the fabric.8.2 Preparation of Loop Specimens Draw two gage markson the specimen which are (1) 250 6 2mm(106 0.05 in.)apart, (2) approximately the same distance from the specimenends, (3) parallel to one another, and (4) perpendicular to thelong direction of the test specimen. F
36、orm a loop by folding thespecimen; then aligning and sewing a seam along the two gagemarks. Use a single-needle stitch, sewing two rows of stitchingand making certain that the beginning and ending stitches donot come loose.4For additional information on obtaining apparatus, equipment, or supplies th
37、atmay be suitable for use in this standard, please visit the ASTM ManufacturersEquipment Directory at www.astm.org.D4964 96 (2012)29. Preparation and Verification of Apparatus9.1 Equip and set-up the CRE-type tensile testing machineaccording to the manufacturers instructions and using thefollowing i
38、nformation:9.1.1 Loop distance around clamps: 250 6 2mm(1060.05 in.).9.1.2 Loading crosshead speed: 500 6 15 mm/min (20 60.5 in./min).9.1.3 Unloading crosshead speed: 500 6 15 mm/min (20 60.5 in./min).9.1.4 Cycling controls: 100 N (20 lbf) force maximum, oras agreed upon. Force must be less than tha
39、t which will causethe fabric to rupture. For low elongation fabrics (below100 %), parties should agree to a slower crosshead speed forloading and unloading, such as 300 6 15 mm/min, or 12.0 60.5 in./min.NOTE 3The slower speed is recommended because the recordingdevices may not be able to keep up wit
40、h the machine at elongations below100 %.9.2 Verification of Position of Clamps:9.2.1 Use one of the procedures described in 9.2.2 through10.2.4 to verify or set the position of the clamps.9.2.2 Use the gage supplied by tensile testing machinemanufacturer.9.2.3 Make and use a paper gage as directed b
41、elow.9.2.3.1 Cut a strip of flexible paper that measures 275 6 2mm by 106 2 mm, or 11.0 6 0.05 in. by 0.5 6 0.05 in.9.2.3.2 From one end of paper strip, measure a distance of250 6 2 mm, or 10.0 6 0.05 in., and draw a line perpendicularto the long axis.9.2.3.3 Place a strip of double-faced tape acros
42、s the strip,and on the short end, coincident with the line.9.2.3.4 Curl the untaped end of the strip to form a loop,aligning the end with the 250 mm, or 10 in., line. Press downon the strip, fastening it to the double-faced tape.9.2.3.5 Place the paper loop around the testing machineclamps with the
43、taped joint between the clamps. See Fig. 1.9.2.3.6 Adjust the clamp spacing until the loop is just snugon the clamp.9.2.3.7 Remove the loop.9.2.3.8 If the anvil diameter is 13 mm (0.5 in.), set the initialanvil spacing so that the distance from the top of the upperanvil to the bottom of the lower an
44、vil is 118 mm or 4.7 in.9.2.3.9 If the anvil diameter is 6.5 mm (0.25 in.) set theinitial anvil setting so that the distance from the top of theupper anvil to the bottom of the lower anvil is 121 mm or 4.9in.NOTE 4The anvil spacing in 9.2.3.8 and 9.2.3.9 will provide a loopcircumference of 250 mm or
45、 10 in.10. Conditioning10.1 Before making any tests for loop tension or stretch,bring the samples to moisture equilibrium for testing in thestandard atmosphere for testing textiles, which is 21 6 1C(70 6 2 F) and 65 6 2 % relative humidity.Allow the samplesto relax, free of loop tension, for a minim
46、um of 16 h. Afterexposure for this time, it may be assumed that moistureequilibrium has been reached. See Practice D1776 for standardconditions for testing textile materials.11. Procedure11.1 Test all specimens in standard atmosphere for testingtextiles, which is 21 6 1C(706 2 F) and 65 6 2 % relati
47、vehumidity.11.2 Mount the specimen with the seam between theclamps.11.3 Cycle the specimen three times and record at least theloading and extension of the third cycle on the chart.11.4 Test the remaining specimens.12. Calculation12.1 Manual Calculation for Loop Tension at SpecifiedElongations:12.1.1
48、 Calculate the extension value for 30 %, 50 %, 70 %elongation using Eq 1L 5 E 3 C! / 200 (1)where:L = extension, mm (in.)E = % elongation, andC = loop circumference, mm (in.)12.1.2 Using the extension values calculated in 12.1.1,determine the loop tension values corresponding to 30 %,50 %, and 70 %
49、elongations, or for the agreed upon percentelongation(s).12.2 Manual Calculation for Elongation at Specified LoopTension:12.2.1 Calculate the percent elongation at the specifiedmaximum loop tension (100 N (20 lbf), or other agreed uponloop tension.12.3 Calculate the average tension (or elongation) for eachspecified elongation (or loop tension), or both, if requested.12.4 Calculate the standard deviation, or the coefficient ofvariation, or both, for each property if requested.13. Report13.1 State that the specimens were tested as directed in TestMethod D4964
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