1、Designation: D2209 00 (Reapproved 2015)Standard Test Method forTensile Strength of Leather1This standard is issued under the fixed designation D2209; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numb
2、er 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.1. Scope1.1 This test method covers the determination of the load
3、required to rupture a leather test specimen having a12-in.(12.7-mm) width. The load to rupture divided by the originalunstretched cross-sectional area gives the tensile strength. Itmay be used for all types of leather that are smooth and firmenough to permit accurate thickness measurements. This tes
4、tmethod does not apply to wet blue.1.2 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of
5、 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:2D1517 Terminology Relating to LeatherD1610 Practice for Conditioning Leather and Leather Prod-ucts for T
6、estingD1813 Test Method for Measuring Thickness of LeatherTest SpecimensD2211 Test Method for Elongation of Leather3. Terminology3.1 For definitions of leather terms used in this standardrefer to Terminology D1517.4. Summary of Test Method4.1 The width and thickness are measured in the center ofthe
7、narrow area of the leather specimen. The specimen isclamped in the testing machine as described in 9.3. The forcerequired to rupture the leather at a jaw separation of 10 6 2in./min. is measured. The tensile strength is calculated in psi orin kPa by dividing the force by the area of the original cro
8、sssection of its narrow section. The percent elongation at ruptureis also measured.5. Significance and Use5.1 The tensile strength test gives a reliable indication of thequality of the leather. Improperly lubricated and partiallydegraded leathers give low values for tensile strength. Theorientation
9、of the specimen in relation to the backbone and thelocation of the specimen on the hide influence the resultssignificantly. This test method is excellent for development,control, specification acceptance, and service evaluation ofleather. This test method may not apply when the conditions oftest emp
10、loyed differ widely from those specified in the testmethod.6. Apparatus6.1 Testing Machine, Power-Driven The applied loadshall be indicated on a dial, scale, or chart. The load indicatorshall record or indicate the maximum load at the time ofrupture of the specimen. The machine shall be equipped wit
11、h aset of grips for clamping the specimens. The faces of the gripsshould be knurled or otherwise roughened to prevent slippingof the specimen. The gripping surfaces shall be at least 1 by 112in. (25.4 by 38 mm). The grips shall be mounted with thelonger dimension perpendicular to the direction of th
12、e appli-cation of the load. The speed of the power-activated grip shallbe uniform speed of 10 6 2 in./ min (254 6 50 mm/min) whenrunning free. The error of the machine up to a load of 50 lbf(222 N) shall not exceed 2 %; at loads of more than 50 lbf theerror shall not exceed 1 %.6.2 Thickness GageAde
13、ad-mass type of thickness gage asdescribed in Test Method D1813.6.3 Steel Scale, graduated to read in 0.02 in. (0.5 mm).6.4 Steel Die, to cut test specimens designed as shown inFig. 1.6.5 Cutting Block, which shall consist of a flat hardwoodsupport upon which is placed a flat, smooth sheet of firmma
14、terial that will not injure the cutting edge of the die.1This test method is under the jurisdiction of ASTM Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.07 on Physical Properties. Thistest method was developed in cooperation with the American Leather ChemistsAssn. (St
15、andard Method E15 1965).Current edition approved May 1, 2015. Published July 2015. Originally approvedin 1963. Last previous edition approved in 2010 as D2209 00 (2010). DOI:10.1520/D2209-00R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
16、erviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17. Test Specimen7.1 The specimen shall be dumbbell in
17、 shape, cut from thetest unit of leather by means of a die as shown in Fig. 1. Thedirection of the long dimension in relation to the backboneshall be noted.8. Conditioning8.1 All specimens shall be conditioned in accordance withPractice D1610. Conditioning other than that prescribed shallbe noted in
18、 the results.9. Procedure9.1 Measure the thickness of the specimen to the nearest0.001 in. (0.025 mm) at one point, the mid-point of the narrowsection.9.2 Measure the width of the narrow section of the spectrumto the nearest 0.02 in. (0.5 mm) at one place on the grain side,at the mid-point. Measure
19、heavy leathers such as belting andsoling, on both flesh and grain sides at the mid-point.9.3 Mount the specimen symmetrically with the distancebetween the jaws 4 618 in. (102 6 3.2 mm).9.4 Determine the elongation of the specimen in accordancewith Test Method D2211.9.5 Record the load in pounds-forc
20、e (or newtons) to rupturethe specimen.9.6 Reject any specimen that slips or breaks within34 to 1in. (19 to 25.4 mm) of the jaws and test a similar specimen.10. Report10.1 Report the following information:10.1.1 Thickness to the nearest 0.001 in. (0.025 mm)reported for each specimen or averaged and r
21、eported as thethickness of the sample.10.1.2 Cross-sectional area of each specimen,NOTE 1Calculate the original cross-sectional area of the specimenfrom one thickness measurement and one width measurement. For heavyleathers average two width measurements.10.1.3 Breaking load to the nearest 1 lbf (4.
22、4 N), reportedfor each specimen or averaged and reported as the breakingload of the sample,10.1.4 Tensile strength to the nearest 10 psi (69 kPa),reported for each specimen or averaged and reported as thetensile strength of the sample, andNOTE 2Calculate the tensile strength by dividing the load in
23、pounds-force (or newtons) required to rupture the specimen by the area in squareinches (or square millimetres) of the original cross section of its narrowsection.10.1.5 Direction of the long axis of the specimen relative tothe backbone.11. Precision and Bias11.1 The following criteria may be used to
24、 judge theacceptability of the results if at least 15 units have been tested:11.1.1 One Operator, Duplicate Specimens, Same SkinResults by the same operator on duplicate adjacent specimensfrom a skin taken from the official sampling location should notbe considered suspect unless the coefficient of
25、variation ex-ceeds:Shoe upperCalfskinA11 %8%A31oz(8528g),0.0468 0.0156 in. (1.189 0.396 mm).11.1.2 Two Laboratories, Duplicate Specimens, SameSkinResults submitted on leathers of the type mentioned in11.1.1 by each of two laboratories on duplicate adjacentspecimens from the same skin taken from the
26、official samplingposition should not be considered suspect unless the average ofthe two results differ by more than 5 %.NOTE 3The reproducibility reported in 11.1.2 is based on dataobtained at two laboratories, each with a different type of testing machineand a different operator. One machine is a l
27、oad-cell type and the other apendulum type. The results show very close correlation between labora-tories.NOTE 4The precision data for between skins are not given because theresults were based on different skins from several production lots. Thevariables in leather for between skins will give a high
28、er variation of theresults, but this factor should not affect the precision of the test method.12. Keywords12.1 leather; strength; tensile strengthin. mm in. mm12 12.7 114 31.878 22 6 1521 25.4 634 171118 28.6NOTE 1The cutting edges shall be beveled on the outside and straighton the inside. The die
29、shall be kept sharp and free of nicks to give clean,even edges on the specimen.FIG. 1 Shape and Dimensions of Die for Cutting Test SpecimensD2209 00 (2015)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard
30、. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed
31、every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible te
32、chnical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoh
33、ocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 00 (2015)3
