1、Designation: D2261 11D2261 13Standard 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 ofor
2、iginal 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.This standard has been approved for use by agencies of the Department of
3、Defense.1. Scope1.1 This test method covers the measurement of the tearing strength of textile fabrics by the tongue (single rip) procedure usinga recording constant-rate-of-extension-type (CRE) tensile testing machine.1.1.1 The CRE-type tensile testing machine has become the preferred test apparatu
4、s for determining tongue tearing strength. Itis recognized that some constant-rate-of-traverse-type (CRT) tensile testing machines continue to be used.As a consequence, thesetest instruments may be used when agreed upon between the purchaser and the supplier. The conditions for use of the CRT-typete
5、nsile tester are included in Appendix X1.1.2 This test method applies to most fabrics including woven fabrics, air bag fabrics, blankets, napped fabrics, knit fabrics,layered fabrics, pile fabrics and non-wovens. The fabrics may be untreated, heavily sized, coated, resin-treated, or otherwisetreated
6、. Instructions are provided for testing specimens with or without wetting.1.3 Tear strength, as measured in this test method, requires that the tear be initiated before testing. The reported value obtainedis not directly related to the force required to initiate or start a tear.1.4 Two calculations
7、for tongue tearing strength are provided: the single-peak force and the average of five highest peak forces.1.5 The values stated in either SI units or inch-pound units are to be regarded as the standard. The inch-pound units may beapproximate.1.6 This standard does not purport to address all of the
8、 safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D76 Specification for Tensile
9、Testing Machines for TextilesD123 Terminology Relating to TextilesD629 Test Methods for Quantitative Analysis of TextilesD1776 Practice for Conditioning and Testing TextilesD2904 Practice for InterlaboratoryTesting of aTextileTest Method that Produces Normally Distributed Data (Withdrawn 2008)3D2906
10、 Practice for Statements on Precision and Bias for Textiles (Withdrawn 2008)3D4848 Terminology Related to Force, Deformation and Related Properties of TextilesD4850 Terminology Relating to Fabrics and Fabric Test Methods3. Terminology3.1 For all terminology relating to D13.60, Fabric Test Methods, S
11、pecific, refer to Terminology D4850.3.2 For all terminology related to Force, Deformation and Related Properties of Textiles, refer to Terminology D4848.1 This test method is under the jurisdiction ofASTM Committee D13 on Textiles and is the direct responsibility of Subcommittee D13.60 on Fabric Tes
12、t Methods, Specific.Current edition approved July 1, 2011Jan. 1, 2013. Published August 2011February 2013. Originally approved in 1964. Discontinued November 1995 and reinstated asD226195. Last previous edition approved in 20072011 as D226107a11.1. DOI: 10.1520/D2261-11.10.1520/D2261-13.2 For refere
13、ncedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on
14、www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of 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 cons
15、ult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.1 The following terms are relev
16、ant 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 terminology related to textiles, refer to Terminology D123.4. Summary of Test Method4.1 A rectangular speci
17、men, cut in the center of a short edge to form a two-tongued (trouser shaped) specimen, in which onetongue of the specimen is gripped in the upper jaw and the other tongue is gripped in the lower jaw of a tensile testing machine.The separation of the jaws is continuously increased to apply a force t
18、o propagate the tear. At the same time, the force developedis recorded.The force to continue the tear is calculated from autographic chart recorders or microprocessor data collection systems.5. Significance and Use5.1 This test method is considered satisfactory for acceptance testing of commercial s
19、hipments since current estimates ofbetween-laboratory precision are acceptable, and the test method is used extensively in the trade for acceptance testing.5.1.1 In case of a dispute arising from differences in reported test results when using this test method for acceptance testing ofcommercial shi
20、pments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical biasbetween their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the twoparties should take a group of test specimens that are as
21、 homogeneous as possible and that are from a lot of fabric of the type inquestion. Test specimens then should be randomly assigned in equal numbers to each laboratory for testing. The average resultsfrom the two laboratories should be compared using the appropriate statistical analysis and an accept
22、able probability level chosenby the two parties before testing is begun. If a bias is found, either its cause must be found and corrected, or the purchaser andthe supplier must agree to interpret future test results with consideration to the known bias.5.2 The force registered in a tear test is irre
23、gular, and as a consequence, empirical methods have had to be developed to obtainusable values related to tear strength. In spite of the empirical nature of the reported values, the values are considered to reflectcomparative performance of similar fabrics tested and measured in the same way. No kno
24、wn procedure is available that can beused with all fabrics to determine the minimum tearing strength.5.3 Depending on the nature of the specimen, the data recording devices will show the tearing force in the form of a peak orpeaks. The highest peaks appear to reflect the strength of the yarn compone
25、nts, fiber bonds, or fiber interlocks, individually or incombination, needed to stop a tear in a fabric of the same construction. The valleys recorded between the peaks have no specificsignificance. The minimum tearing force, however, is indicated to be above the lowest valleys.5.4 Most textile fabr
26、ics can be tested by this test method. Some modification of clamping techniques may be necessary for agiven fabric due to its structure. Strong fabrics or fabrics made from glass fibers usually require special adaptation to prevent themfrom slipping in the clamps or being damaged as a result of bein
27、g gripped in the clamps.5.5 The CRE-type tensile testing machine has become the preferred test apparatus for determining tongue tearing strength. Itis recognized that some constant-rate-of-traverse-type (CRT) tensile testing machines continue to be used. Consequently, these testinstruments may be us
28、ed when agreed upon between the purchaser and the supplier. The conditions for use of the CRT-type testerare included in Appendix X1.6. Apparatus6.1 Tensile Testing Machine4, of the CRE-type conforming to the requirements of Specification D76 with autographic recorder,or automatic microprocessor dat
29、a gathering system.6.2 Clamps, having all gripping surfaces parallel, flat, and capable of preventing slipping of the specimen during a test, andmeasuring at least 25 by 75 mm (1 by 3 in.) with the longer dimension perpendicular to the direction of application of the force.6.2.1 The use of hydraulic
30、 or pneumatic clamping systems with a minimum of 25 by 75-mm (1 by 3-in.) rubber grippingsurfaces or serrated having an appropriate clamping force at the grip faces depending on the type of fabric under test. The pressureshould be sufficient to prevent slippage of the specimen in the gripping surfac
31、e during the test, while ensuring the specimen is notdamaged at the grip edge. Manual clamping is permitted providing no slippage of the specimen is observed.6.2.2 For some materials, to prevent slippage when using jaw faces other than serrated, such as rubber-faced jaws, the jaw facesmay be covered
32、 with a No. 80 to 120 medium-grit emery cloth. Secure the emery cloth to the jaw faces with pressure-sensitivetape.6.3 Cutting Die or Template, having essentially the shape and dimensions shown in Fig. 1.4 Apparatus is commercially available.D2261 1327. Sampling and Test Specimens7.1 Lot SampleAs a
33、lot sample for acceptance testing, randomly select the number of rolls or pieces of fabric directed in anapplicable material specification or other agreement between the purchaser and the supplier. Consider the rolls or pieces of fabricto be the primary sampling units. In the absence of such an agre
34、ement, take the number of fabric rolls specified in Table 1.NOTE 1An adequate specification or other agreement between the purchaser and the supplier requires taking into account the variability between rollsor pieces of fabric and between specimens from a swatch from a roll or piece of fabric to pr
35、ovide a sampling plan with a meaningful producers risk,consumers risk, acceptable quality level, and limiting quality level.7.2 Laboratory SampleFor acceptance testing, take a swatch extending the width of the fabric and approximately 1 m (1 yd)along the machine direction from each roll or piece in
36、the lot sample. For rolls of fabric, take a sample that will exclude fabricfrom the outer wrap of the roll or the inner wrap around the core of the roll of fabric.7.3 Test SpecimensFrom each laboratory sampling unit, take five specimens from the machine direction and five specimensfrom the cross-mac
37、hine direction, for each test condition described in 9.1 and 9.2, as applicable to a material specification orcontract order.7.3.1 Direction of TestConsider the short direction as the direction of test.7.3.2 Cutting Test SpecimensCut rectangular specimens 75 by 200 mm 6 1 mm (3 by 8 in. 6 0.05 mm).
38、Use the cutting dieor template described in 6.3 and shown in Fig. 1. Take the specimens to be used for the measurement of machine direction withthe longer dimension parallel to the cross-machine direction. Take the specimens to be used for the measurement of thecross-machine direction with the longe
39、r dimension parallel to the machine direction. Make a preliminary cut 75 mm 6 1 mm (3in. 6 0.05 in.) long at the center of the 75-mm (3-in.) width as shown in Fig. 1. When specimens are to be tested wet, take thespecimens from areas adjacent to the dry test specimens. Label to maintain specimen iden
40、tity.7.3.2.1 In cutting the specimens, take care to align the yarns running in the long direction parallel with the die such that whenthe slit is cut, the subsequent tear will take place between these yarns and not across them. This precaution is most important whentesting bowed fabrics.7.3.2.2 Take
41、 specimens representing a broad distribution across the width and length, preferably along the diagonal of thelaboratory sample, and no nearer the edge than one tenth its width. Ensure specimens are free of folds, creases, or wrinkles.Avoidgetting oil, water, grease, and so forth, on the specimens w
42、hen handling.8. Preparation of Test Apparatus and Calibration8.1 Set the distance between the clamps at the start of the test at 75 6 1 mm (3.0 6 0.05 in.).8.2 Select the full-scale force range of the testing machine such that the maximum force occurs between 10 and 90 % offull-scale force.NOTE 1All
43、 dimensions in mm.FIG. 1 Template for Marking and Cutting Tongue Tear SpecimensTABLE 1 Number of Rolls or Pieces of Fabric in the Lot SampleNumber of Rolls or Piecesin Lot, Inclusive Number of Rolls or Pieces in Lot Sample1 to 3 all4 to 24 425 to 50 5over 50 10 % to a maximum of 10 rolls or piecesD2
44、261 1338.3 Set the testing speed to 50 6 2 mm/min (2 6 0.1 in./min). When agreed upon between the purchaser and the supplier, thetesting speed may be set to 300 6 10 mm/min (12 6 0.5 in./min).8.4 Verify calibration of the tensile testing machine as directed in the manufacturers instructions.8.5 When
45、 using microprocessor automatic data gathering systems, 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 approximate moisture equilibri
46、um in the standard atmosphere forpreconditioning textiles as specified in Practice D1776, unless otherwise specified in a material specification or contract order.9.1.2 After preconditioning, bring the test specimens to moisture equilibrium for testing in the standard atmosphere for testingtextiles
47、as specified in Practice D1776 or, if applicable, in the specified atmosphere in which the testing is to be performed, unlessotherwise specified in a material specification or contract order. In addition to conditioning it is important for fabrics with stretchcharacteristics to relax for a period of
48、 24 h prior to sample preparation.9.2 Condition 2, Wet Specimen Testing Conditioning:9.2.1 When desizing treatments are specified prior to wet testing, use desizing treatments that will not affect the normal physicalproperty of the fabric as specified in Test Method D629.9.2.2 Submerge the specimens
49、 in a container of distilled or deionized water at ambient temperature until thoroughly soaked (see9.2.2.1).9.2.2.1 The time of immersion must be sufficient to wet out the specimens as indicated by no significant change in tearing forcefollowed by longer periods of immersion. For most fabrics this time period will be about 1 h. For fabrics not readily wet out withwater, such as those treated with water-repellent or water-resistant materials, add a 0.1 % solution of a nonionic wetting agent tothe water bath.10. Procedure10.1 Test the conditioned specimens in the stan
