1、Designation: D2261 11Standard Test Method forTearing Strength of Fabrics by the Tongue (Single Rip)Procedure (Constant-Rate-of-Extension Tensile TestingMachine)1This standard is issued under the fixed designation D2261; the number immediately following the designation indicates the year oforiginal a
2、doption 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.This standard has been approved for use by agencies of the Department of Defense.
3、1. Scope1.1 This test method covers the measurement of the tearingstrength of textile fabrics by the tongue (single rip) procedureusing a recording constant-rate-of-extension-type (CRE) ten-sile testing machine.1.1.1 The CRE-type tensile testing machine has become thepreferred test apparatus for det
4、ermining tongue tearingstrength. It is recognized that some constant-rate-of-traverse-type (CRT) tensile testing machines continue to be used. As aconsequence, these test instruments may be used when agreedupon between the purchaser and the supplier. The conditionsfor use of the CRT-type tensile tes
5、ter are included in AppendixX1.1.2 This test method applies to most fabrics includingwoven fabrics, air bag fabrics, blankets, napped fabrics, knitfabrics, layered fabrics, pile fabrics and non-wovens. Thefabrics may be untreated, heavily sized, coated, resin-treated,or otherwise treated. Instructio
6、ns are provided for testingspecimens with or without wetting.1.3 Tear strength, as measured in this test method, requiresthat the tear be initiated before testing. The reported valueobtained is not directly related to the force required to initiateor start a tear.1.4 Two calculations for tongue tear
7、ing strength are pro-vided: the single-peak force and the average of five highestpeak forces.1.5 The values stated in either SI units or inch-pound unitsare to be regarded as the standard. The inch-pound units maybe approximate.1.6 This standard does not purport to address all of thesafety concerns,
8、 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. Referenced Documents2.1 ASTM Standards:2D76 Specification for Tensile Testing Machin
9、es for TextilesD123 Terminology Relating to TextilesD629 Test Methods for Quantitative Analysis of TextilesD1776 Practice for Conditioning and Testing TextilesD2904 Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed DataD2906 Practice for Statements on Pr
10、ecision and Bias forTextiles3D4848 Terminology Related to Force, Deformation andRelated Properties of TextilesD4850 Terminology Relating to Fabrics and Fabric TestMethods3. Terminology3.1 For all terminology relating to D13.60, Fabric TestMethods, Specific, refer to Terminology D4850.3.2 For all ter
11、minology related to Force, Deformation andRelated Properties of Textiles, refer to Terminology D4848.3.2.1 The following terms are relevant to this standard:cross-machine direction, CD, fabric, machine direction, MD,peak force, in tear testing of fabrics, tearing force, in fabric,tearing strength, i
12、n fabric.3.3 For all other terminology related to textiles, refer toTerminology D123.4. Summary of Test Method4.1 A rectangular specimen, cut in the center of a short edgeto form a two-tongued (trouser shaped) specimen, in which onetongue of the specimen is gripped in the upper jaw and theother tong
13、ue is gripped in the lower jaw of a tensile testingmachine. The separation of the jaws is continuously increasedto apply a force to propagate the tear. At the same time, the1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D
14、13.60 on Fabric Test Methods,Specific.Current edition approved July 1, 2011. Published August 2011. Originallyapproved in 1964. Discontinued November 1995 and reinstated as D226195. Lastprevious edition approved in 2007 as D226107a1. DOI: 10.1520/D2261-11.2For referenced ASTM standards, visit the AS
15、TM 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.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright
16、 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.force developed is recorded. The force to continue the tear iscalculated from autographic chart recorders or microprocessordata collection systems.5. Significance and Use5.1 This test method is c
17、onsidered satisfactory for accep-tance testing of commercial shipments since current estimatesof between-laboratory precision are acceptable, and the testmethod is used extensively in the trade for acceptance testing.5.1.1 In case of a dispute arising from differences inreported test results when us
18、ing this test method for acceptancetesting of commercial shipments, the purchaser and the sup-plier should conduct comparative tests to determine if there isa statistical bias between their laboratories. Competent statis-tical assistance is recommended for the investigation of bias.As a minimum, the
19、 two parties should take a group of testspecimens that are as homogeneous as possible and that arefrom a lot of fabric of the type in question. Test specimens thenshould be randomly assigned in equal numbers to eachlaboratory for testing. The average results from the twolaboratories should be compar
20、ed using the appropriate statis-tical analysis and an acceptable probability level chosen by thetwo parties before testing is begun. If a bias is found, either itscause must be found and corrected, or the purchaser and thesupplier must agree to interpret future test results with consid-eration to th
21、e known bias.5.2 The force registered in a tear test is irregular, and as aconsequence, empirical methods have had to be developed toobtain usable values related to tear strength. In spite of theempirical nature of the reported values, the values are consid-ered to reflect comparative performance of
22、 similar fabricstested and measured in the same way. No known procedure isavailable that can be used with all fabrics to determine theminimum tearing strength.5.3 Depending on the nature of the specimen, the datarecording devices will show the tearing force in the form of apeak or peaks. The highest
23、 peaks appear to reflect the strengthof the yarn components, fiber bonds, or fiber interlocks,individually or in combination, needed to stop a tear in a fabricof the same construction. The valleys recorded between thepeaks have no specific significance. The minimum tearingforce, however, is indicate
24、d to be above the lowest valleys.5.4 Most textile fabrics can be tested by this test method.Some modification of clamping techniques may be necessaryfor a given fabric due to its structure. Strong fabrics or fabricsmade from glass fibers usually require special adaptation toprevent them from slippin
25、g in the clamps or being damaged asa result of being gripped in the clamps.5.5 The CRE-type tensile testing machine has become thepreferred test apparatus for determining tongue tearingstrength. It is recognized that some constant-rate-of-traverse-type (CRT) tensile testing machines continue to be u
26、sed.Consequently, these test instruments may be used when agreedupon between the purchaser and the supplier. The conditionsfor use of the CRT-type tester are included in Appendix X1.6. Apparatus6.1 Tensile Testing Machine4, of the CRE-type conformingto the requirements of Specification D76 with auto
27、graphicrecorder, or automatic microprocessor data gathering system.6.2 Clamps, having all gripping surfaces parallel, flat, andcapable of preventing slipping of the specimen during a test,and measuring at least 25 by 75 mm (1 by 3 in.) with the longerdimension perpendicular to the direction of appli
28、cation of theforce.6.2.1 The use of hydraulic or pneumatic clamping systemswith a minimum of 25 by 75-mm (1 by 3-in.) rubber grippingsurfaces or serrated having an appropriate clamping force at thegrip faces depending on the type of fabric under test. Thepressure should be sufficient to prevent slip
29、page of the speci-men in the gripping surface during the test, while ensuring thespecimen is not damaged at the grip edge. Manual clamping ispermitted providing no slippage of the specimen is observed.6.2.2 For some materials, to prevent slippage when usingjaw faces other than serrated, such as rubb
30、er-faced jaws, thejaw faces may be covered with a No. 80 to 120 medium-gritemery cloth. Secure the emery cloth to the jaw faces withpressure-sensitive tape.6.3 Cutting Die or Template, having essentially the shapeand dimensions shown in Fig. 1.7. Sampling and Test Specimens7.1 Lot SampleAs a lot sam
31、ple for acceptance testing,randomly select the number of rolls or pieces of fabric directedin an applicable material specification or other agreementbetween the purchaser and the supplier. Consider the rolls orpieces of fabric to be the primary sampling units. In theabsence of such an agreement, tak
32、e the number of fabric rollsspecified in Table 1.NOTE 1An adequate specification or other agreement between thepurchaser and the supplier requires taking into account the variabilitybetween rolls or pieces of fabric and between specimens from a swatchfrom a roll or piece of fabric to provide a sampl
33、ing plan with a meaningfulproducers risk, consumers risk, acceptable quality level, and limitingquality level.7.2 Laboratory SampleFor acceptance testing, take aswatch extending the width of the fabric and approximately 1m (1 yd) along the machine direction from each roll or piece inthe lot sample.
34、For rolls of fabric, take a sample that willexclude fabric from the outer wrap of the roll or the inner wraparound the core of the roll of fabric.7.3 Test SpecimensFrom each laboratory sampling unit,take five specimens from the machine direction and fivespecimens from the cross-machine direction, fo
35、r each testcondition described in 9.1 and 9.2, as applicable to a materialspecification or contract order.7.3.1 Direction of TestConsider the short direction as thedirection of test.7.3.2 Cutting Test SpecimensCut rectangular specimens75 by 200 mm 6 1mm(3by8in.6 0.05 mm). Use the cuttingdie or templ
36、ate described in 6.3 and shown in Fig. 1. Take thespecimens to be used for the measurement of machine direction4Apparatus is commercially available.D2261 112with the longer dimension parallel to the cross-machine direc-tion. Take the specimens to be used for the measurement of thecross-machine direc
37、tion with the longer dimension parallel tothe machine direction. Make a preliminary cut 75 mm 6 1mm(3 in. 6 0.05 in.) long at the center of the 75-mm (3-in.) widthas shown in Fig. 1. When specimens are to be tested wet, takethe specimens from areas adjacent to the dry test specimens.Label to maintai
38、n specimen identity.7.3.2.1 In cutting the specimens, take care to align the yarnsrunning in the long direction parallel with the die such thatwhen the slit is cut, the subsequent tear will take place betweenthese yarns and not across them. This precaution is mostimportant when testing bowed fabrics
39、.7.3.2.2 Take specimens representing a broad distributionacross the width and length, preferably along the diagonal ofthe laboratory sample, and no nearer the edge than one tenth itswidth. Ensure specimens are free of folds, creases, or wrinkles.Avoid getting oil, water, grease, and so forth, on the
40、 specimenswhen handling.8. Preparation of Test Apparatus and Calibration8.1 Set the distance between the clamps at the start of thetest at 75 6 1 mm (3.0 6 0.05 in.).8.2 Select the full-scale force range of the testing machinesuch that the maximum force occurs between 10 and 90 % offull-scale force.
41、8.3 Set the testing speed to 50 6 2 mm/min (2 6 0.1in./min). When agreed upon between the purchaser and thesupplier, the testing speed may be set to 300 6 10 mm/min (126 0.5 in./min).8.4 Verify calibration of the tensile testing machine asdirected in the manufacturers instructions.8.5 When using mic
42、roprocessor automatic data gatheringsystems, set the appropriate parameters as specified in themanufacturers instructions and Specification D76.9. Conditioning9.1 Condition 1, Standard Testing Conditioning:9.1.1 Precondition the specimens by bringing them to ap-proximate moisture equilibrium in the
43、standard atmosphere forpreconditioning textiles as specified in Practice D1776, unlessotherwise specified in a material specification or contract order.9.1.2 After preconditioning, bring the test specimens tomoisture equilibrium for testing in the standard atmosphere fortesting textiles as specified
44、 in Practice D1776 or, if applicable,in the specified atmosphere in which the testing is to beperformed, unless otherwise specified in a material specifica-tion or contract order. In addition to conditioning it is importantfor fabrics with stretch characteristics to relax for a period of24 h prior t
45、o sample preparation.9.2 Condition 2, Wet Specimen Testing Conditioning:9.2.1 When desizing treatments are specified prior to wettesting, use desizing treatments that will not affect the normalphysical property of the fabric as specified in Test MethodD629.9.2.2 Submerge the specimens in a container
46、 of distilled ordeionized water at ambient temperature until thoroughlysoaked (see 9.2.2.1).9.2.2.1 The time of immersion must be sufficient to wet outthe specimens as indicated by no significant change in tearingforce followed by longer periods of immersion. For mostfabrics this time period will be
47、 about 1 h. For fabrics notreadily wet out with water, such as those treated with water-repellent or water-resistant materials, add a 0.1 % solution of anonionic wetting agent to the water bath.10. Procedure10.1 Test the conditioned specimens in the standard atmo-sphere for testing textiles, which i
48、s 21 6 1C (70 6 2F) and65 6 2 % relative humidity, unless otherwise specified in amaterial specification or contract order.10.2 Secure the specimen in the clamp jaws with the slitedge of each tongue centered in such a manner that theNOTEAll dimensions in mm.FIG. 1 Template for Marking and Cutting To
49、ngue Tear SpecimensTABLE 1 Number of Rolls or Pieces of Fabric in the Lot SampleNumber of Rolls or Piecesin Lot, InclusiveNumber of Rolls or Pieces in Lot Sample1to3 all4to24 425 to 50 5over 50 10 % to a maximum of 10 rolls or piecesD2261 113originally adjacent cut edges of the tongues form a straight linejoining the centers of the clamps and the two tongues presentopposite faces of the fabric to the operator. See Fig. 2.10.2.1 For wet testing, remove a specimen from the water,and immediately mount it on the testing machine in the normalsetup. Perform the test within
