1、Designation: D 2261 07aStandard 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 D 2261; the number immediately following the designation indicates the year oforigina
2、l adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defe
3、nse.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
4、 determining 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
5、 tester 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. The fabrics may beuntreated, heavily sized, coated, resin-treated, or otherwisetreated. Instructions are prov
6、ided for testing specimens with orwithout 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 tearing strengt
7、h 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, if any, as
8、sociated 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 Machines for Text
9、ilesD 123 Terminology Relating to TextilesD 629 Test Methods for Quantitative Analysis of TextilesD 1776 Practice for Conditioning and Testing TextilesD 2904 Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed DataD 2906 Practice for Statements on Precisio
10、n and Bias forTextilesD 4848 Terminology of Force, Deformation and RelatedProperties of TextilesD 4850 Terminology Relating to Fabric3. Terminology3.1 For all terminology relating to D13.60, Fabric TestMethods, Specific, refer to Terminology D 4850.3.2 For all terminology related to Force, Deformati
11、on andRelated Properties of Textiles, refer to Terminology D 4848.3.2.1 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, in fabric.3.3 For all other terminol
12、ogy related to textiles, refer toTerminology D 123.4. 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 tongue is gripped in the lower jaw of
13、a tensile testingmachine. The separation of the jaws is continuously increasedto apply a force to propagate the tear. At the same time, theforce developed is recorded. The force to continue the tear iscalculated from autographic chart recorders or microprocessordata collection systems.1This test met
14、hod is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.60 on Fabric Test Methods,Specific.Current edition approved Dec. 1, 2007. Published January 2008. Originallyapproved in 1964. Discontinued November 1995 and reinstated as D 226195. Las
15、tprevious edition approved in 2007 as D 226107.2For 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.1Copyright AST
16、M International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Copyright by ASTM Intl (all rights reserved); Fri May 9 03:03:14 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.5. Significance and U
17、se5.1 This test method is considered 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 inre
18、ported test results when using 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 investigatio
19、n of bias.As a minimum, the 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 twola
20、boratories should be compared 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 result
21、s with consid-eration to the 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
22、 comparative performance of 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
23、apeak or peaks. The highest 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 tearing
24、force, however, is indicated 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
25、toprevent them from slipping in the clamps or being damaged asa result of being gripped in the clamps.5.5 The CRE-type is the preferred tensile testing machine.This test method allows the use of the CRT-type tensilemachine when agreed upon between the purchaser and thesupplier. There may be no overa
26、ll correlation, however, be-tween the results obtained with the CRT-type machine and theCRE-type machine. Consequently, these two tensile testerscannot be used interchangeably unless the degree of quantita-tive correlation has been established between the purchaser andthe supplier. In any event, the
27、 CRE-type machine shall prevail.6. Apparatus6.1 Tensile Testing Machine3, of the CRE-type conformingto the requirements of Specification D76 with autographicrecorder, or automatic microprocessor data gathering system.6.2 Clamps, having all jaw surfaces parallel, flat, andcapable of preventing slippi
28、ng 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 application of theforce.6.2.1 The use of hydraulic pneumatic clamping systemswith a minimum of 50 by 75-mm (2 by 3-in.) serrated or rubberjaw faces having a cla
29、mping force at the grip faces of 13 to 14kN (2900 to 3111 lbf) is recommended. 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 rubber-faced jaws, thejaw faces may be covered w
30、ith 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 sample for acceptance testing,randomly select t
31、he 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, take the number of fabric rollsspecified in Tab
32、le 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 sampling plan with a meaningfulproducers risk, co
33、nsumers 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. For rolls of fabric, take a sample that will
34、3Apparatus is commercially available.FIG. 1 Template for Marking and Cutting Tongue Tear Specimens,All Tolerances 60.5 %D 2261 07a2Copyright by ASTM Intl (all rights reserved); Fri May 9 03:03:14 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions au
35、thorized.exclude 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, for each testcondition described in 9
36、.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 (3 by 8 in.). Use the cutting die or templatedescribed in 6.3 and shown in Fig. 1. Take
37、 the specimens to beused for the measurement of machine direction with the longerdimension parallel to the cross-machine direction. Take thespecimens to be used for the measurement of the cross-machine direction with the longer dimension parallel to themachine direction. Make a preliminary cut 75 mm
38、 (3 in.) longat the center of the 75-mm (3-in.) width as shown in Fig. 1.When specimens are to be tested wet, take the specimens fromareas adjacent to the dry test specimens. Label to maintainspecimen identity.7.3.2.1 In cutting the specimens, take care to align the yarnsrunning in the long directio
39、n 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.7.3.2.2 Take specimens representing a broad distributionacross the width and length, preferably along the dia
40、gonal 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 specimenswhen handling.8. Preparation of Test Apparatus and Calibration8.1 Set the distance between the clamp
41、s 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.8.3 Set the testing speed to 50 6 2 mm/min (2 6 0.1in./min). When agreed upon between the purchaser and thesup
42、plier, 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 microprocessor automatic data gatheringsystems, set the appropriate parameters as specified in themanufacturers i
43、nstructions 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 standard atmosphere forpreconditioning textiles as specified in Practice D 1776, unlessotherwise specified in
44、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 in Practice D 1776 or, if applicable,in the specified atmosphere in which the testing is to beperformed, unl
45、ess otherwise specified in a material specifica-tion or contract order.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 Meth
46、odD 629.9.2.2 Submerge the specimens in a container 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
47、immersion. For mostfabrics this time period will be 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
48、 standard atmo-sphere for testing textiles, which is 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 theoriginally adjac
49、ent 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.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 2 min after removal of thespecimen from the water. If more than 2 min elapse betweentaking the wet specimen from the water bath and starting thetensile testing machine, discard the specimen and take another.10.3 Start the machine and record the tearing force on therecordi
