1、Designation: D1424 09 (Reapproved 2013)1Standard Test Method forTearing Strength of Fabrics by Falling-Pendulum(Elmendorf-Type) Apparatus1This standard is issued under the fixed designation D1424; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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 U.S. Department of Defense.1NOTEIn Table A3.1
3、, typographical errors in the Useable Test Ranges were corrected editorially in January 2015.1. Scope1.1 This test method covers the determination of the forcerequired to propagate a single-rip tear starting from a cut in afabric and using a falling-pendulum (Elmendorf-Type) appa-ratus.1.2 This test
4、 method applies to most fabrics includingwoven, layered blankets, napped pile, blanket, and air bagfabrics, provided the fabric does not tear in the directioncrosswise to the direction of the force application during thetest. The fabrics may be untreated, heavily sized, coated,resin-treated, or othe
5、rwise treated. Instructions are provided fortesting specimens with, or without, wetting.1.3 This test method is suitable only for the warp directiontests of warp-knit fabrics. It is not suited for the coursedirection of warp knit fabrics or either direction of most otherknitted fabrics.1.4 The value
6、s stated in either SI units or U.S. customaryunits are to be regarded as standard, but must be usedindependently of each other. The U.S. customary units may beapproximate.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility
7、 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:2D123 Terminology Relating to TextilesD629 Test Methods for Quantitative Analysis of TextilesD1776 Pra
8、ctice for Conditioning and Testing TextilesD2261 Test Method for Tearing Strength of Fabrics by theTongue (Single Rip) Procedure (Constant-Rate-of-Extension Tensile Testing Machine)D2904 Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed Data (With-drawn
9、2008)3D2906 Practice for Statements on Precision and Bias forTextiles (Withdrawn 2008)3D4848 Terminology Related to Force, Deformation andRelated Properties of TextilesD4850 Terminology Relating to Fabrics and Fabric TestMethodsD5587 Test Method for Tearing Strength of Fabrics byTrapezoid Procedure3
10、. Terminology3.1 For all terminology relating to D13.59, Fabric TestMethods, General, refer to Terminology D4850.3.2 For all terminology relating to Force, Deformation andRelated Properties in Textiles, refer to Terminology D4848.3.2.1 The following terms are relevant to this standard:cross-machine
11、direction, CD, length of tear, machine direction,MD, tearing energy, tearing force, tear resistance, tearingstrength, fabric.3.3 For all other terminology related to textiles, refer toTerminology D123.4. Summary of Test Method4.1 A slit is centrally precut in a test specimen held betweentwo clamps a
12、nd the specimen is torn through a fixed distance.The resistance to tearing is in part factored into the scalereading of the instrument and is computed from this readingand the pendulum capacity.1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibil
13、ity of Subcommittee D13.60 on Fabric Test Methods,Specific.Current edition approved July 1, 2013. Published September 2013. Originallyapproved in 1956. Last previous edition approved in 2009 as D1424 09. DOI:10.1520/D1424-09R13E01.2For referenced ASTM standards, visit the ASTM website, www.astm.org,
14、 orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor
15、Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Significance and Use5.1 This test method for the determination of tearingstrength by the falling pendulum type apparatus is used in thetrade for the acceptance testing of commercial shipments offabrics, but caution is advised sin
16、ce technicians may fail to getgood agreement between results on certain fabrics. Compara-tive tests as directed in 5.1.1 may be needed.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 purchaser
17、and the sup-plier should conduct comparative tests to determine if there isa statistical bias between their laboratories. Statistical assis-tance is recommended for the investigation of bias. As aminimum, the two parties should take a group of test speci-mens that are as homogeneous as possible and
18、that are from alot of fabric of the type in question. The test specimens shouldthen be randomly assigned in equal numbers to each laboratoryfor testing. The average results from the two laboratoriesshould be compared using appropriate statistical analysis andan acceptable probability level chosen by
19、 the two parties beforethe testing began. If a bias is found, either its cause must befound and corrected or the purchaser and the supplier mustagree to interpret future test results with consideration to theknown bias.5.2 Microprocessor systems for automatic collection of datacan provide economical
20、 and reliable results when properlycalibrated. See Test Methods D2261 and D5587.6. Apparatus6.1 Falling-Pendulum (Elmendorf-Type) Tester4The testerincludes: a stationary clamp, a clamp carried on a pendulumthat is free to swing on a bearing, means for leveling asapplicable, means for holding the pen
21、dulum in a raisedposition, means for instantly releasing the pendulum, andmeans for measuring the force to tear the test specimen.6.1.1 A knife can be mounted on a stationary post for initialslitting of the specimens centered between the clamps andadjusted in height to give a tearing distance of 43.
22、0 6 0.15 mm(1.69 6 0.005 in.); that is, the distance between the end of theslit made by the knife and the upper edge of the specimen is43.0 6 0.15 mm (1.69 6 0.005 in.) when the lower edge of the63.0-mm (2.5 6 0.005 in.) wide specimen rests against thebottom of the clamp.6.1.2 With the pendulum in i
23、ts initial position ready for atest, the two clamps are separated by a distance of 2.5 6 0.25mm (0.1 6 0.01 in.) and are aligned such that the clampedspecimen lies in a plane parallel to the axis of the pendulum,the plane making an angle of 0.480 rad (27.5 6 0.5) with theperpendicular line joining t
24、he axis and the horizontal lineformed by the top edges of the clamping jaws. The distancebetween the axis and the top edges of the clamping jaws is1036 0.1 mm (4.055 6 0.004 in.). The clamping surface ineach jaw is at least 25 mm (1.0 in.) wide and 15.9 6 0.1 mm(0.625 6 0.004 in.) deep.6.1.3 The tes
25、ter may have a pointer mounted on the sameaxis as the pendulum to register the tearing force, or it may besubstituted by means of calculating and displaying the requiredresults without the use of a pointer, such as digital display andcomputer driven systems. Preferably the clamps may be airactuated,
26、 but manual clamping is permitted.6.1.4 The test instrument should be equipped to provideinterchangeable full scale force ranges. Typical full scaleranges are shown in Table A3.1.6.2 Calibration Weight(s) for graduation of 50 % of the fullscale force range, or other means as described by the manu-fa
27、cturer of the test apparatus.6.3 Cutting Die having essentially the shape and dimensionsshown in Fig. 1(a) or (b). Either die provides the basicrectangular test specimen 100 6 2mm(46 0.05 in.) long by63 6 0.15 mm (2.5 6 0.005 in.) wide, along with additionalfabric at the top edge of the specimen to
28、help ensure the bottomportion of specimen will be torn during the test. The criticaldimension of the test specimen is the distance 43.0 6 0.15 mm(1.696 0.005 in.) which is to be torn during the test.NOTE 1The improved die model shown in Fig. 1(a) has two newfeatures not found in the original model,
29、Fig. 1(b), namely a cutout for thebottom of the specimen to aid in centering it in the clamps, and (optional)provision for cutting the 20.0 mm (0.75 in.) slit prior to inserting thespecimen in the tester. These dies can be made to order by most diemanufacturers.6.4 Air Pressure Regulator, capable of
30、 controlling gage airpressure between 410 kPa and 620 kPa (60 psi and 90 psi),when applicable, for air clamps.6.5 Setting Gage for Cutting Blade that will provide a cutslit that leaves a 43 6 0.15 mm (1.69 6 0.005 in.) specimentearing distance for a 63 6 0.15 mm (2.5 6 0.005 in.) widespecimen, or eq
31、uivalent.6.6 Jaw Spacing Gage 2.5 6 0.25 mm (0.1 6 0.01 in.)width, or equivalent.6.7 Oil, light weight, non-gumming clock type.6.8 Silicone Grease, when applicable, for air clamp lubri-cation.6.9 Vacuum Cleaner, when applicable, for cleaning dust andfiber from sensor, or equivalent.7. Sampling and T
32、est Specimens7.1 Lot SampleAs a lot sample for acceptance testing,randomly select the number of rolls or pieces of fabric directedin an applicable material specification or other agreement4Apparatus is commercially available. FIG. 1 Die Diagram for Cutting Notched SpecimensD1424 09 (2013)12between t
33、he 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 rollsor pieces specified in Table 1.NOTE 2An adequate specification or other agreement between thepurchaser and supplier requires takin
34、g into account the variability betweenrolls or pieces of fabric and between specimens from a swatch from a rollor piece of fabric to provide a sampling plan with a meaningful producersrisk, consumers risk, acceptable quality level, and limiting quality level.7.2 Laboratory SampleFor acceptance testi
35、ng, 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 willexclude fabric from the outer wrap of the roll or the inner wraparound the core of the roll of fabric.7.3 T
36、est SpecimensFrom each laboratory sampling unit,take five specimens from the machine direction and fivespecimens from the cross-machine direction, for each testcondition described in 9.1 and 9.2, as applicable to a materialspecification or contract order.7.3.1 Direction of TestConsider the long dire
37、ction of thespecimen as the direction of test.7.3.2 Cutting Test SpecimensTake the specimens to beused for the measurement of machine direction with the longerdimension parallel to the machine direction. Take the speci-mens to be used for the measurement of the cross-machine withthe longer dimension
38、 parallel to the cross-machine direction.Use the cutting die described in 6.3 and shown in Fig. 1(a) or(b), as applicable. When specimens are to be tested wet, cutfrom areas adjacent to the dry test specimens. Label tomaintain specimen identity.7.3.2.1 In cutting the woven fabric specimens, take car
39、e toalign the yarns running in the short direction parallel with thedie such that when the slit is cut, the subsequent tear will takeplace between these yarns and not across them. This precautionis most important when testing bowed fabrics.7.3.2.2 Cut specimens representing a broad distributionacros
40、s the width and length, and preferably along the diagonalof the laboratory sample, and no nearer the edge than one-tenthits width. Ensure specimens are free of folds, creases, orwrinkles.Avoid getting oil, water, grease, etc. on the specimenswhen handling.NOTE 3The reading obtained is directly propo
41、rtional to the length ofthe material torn, therefore, it is essential that the specimen be prepared tothe exact size specified.8. Preparation of Apparatus and Calibration8.1 Select test instrument force range, such that the tearoccurs between 20 and 80 % or 20 and 60 % of the full-scalerange as appl
42、icable. Ensure the clamps are spaced as directedin A1.4.NOTE 4For standard test apparatus, the useable portion of the fullscale force range is 20 to 80 %. For the high capacity test instrument, theuseable portion of the full scale force range is 20 to 60 %.8.2 When equipped with a registering sensor
43、, examine thescale and the complementary sensor, as applicable. Using careand without touching the sensor, vacuum away any loose fibersand dust.8.3 Examine the knife edge for sharpness, wear, and centralalignment as directed in A1.5 A1.7.8.4 For air clamps, set the air gage pressure to the clamps to
44、about 550 kPa (80 psi).8.4.1 Maximum gage pressure should be no more than 620kPa (90 psi) and minimum gage pressure no less than 410 kPa(60 psi).8.5 When using microprocessor automatic data gatheringsystems, set the appropriate parameters as defined in themanufacturers instructions.8.6 Verify the ca
45、libration of the selected pendulum full scaleforce range using the procedure described in Annex A2, unlessotherwise specified.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 atmospher
46、e forpreconditioning textiles as directed in Practice D1776, unlessotherwise directed 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 directed in Practice D1776 or
47、, if applicable,in the specified atmosphere in which the testing is to beperformed, unless otherwise directed in a material specificationor 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
48、 will not affect the normalphysical property of the fabric as directed in Test MethodD629.9.2.2 Submerge the specimens in a container of distilled ordeionized water at ambient temperature until thoroughlysoaked (see 8.2.1.1).9.2.2.1 The time of immersion must be sufficient to wet outthe specimens, a
49、s indicated by no significant change in tearingforce followed by longer periods of 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 ofa nonionic wetting agent to the water bath.10. Procedure10.1 Test the conditioned specimens in the standard atmo-sphere for testing textiles, which is 21 6 1C (70 6 2F) and65 6 2 % relative humidity, unless otherwise directed in amaterial specification or contract order.10.2 Posit
