1、Designation: D2212 00 (Reapproved 2015)Standard Test Method forSlit Tear Resistance of Leather1This standard is issued under the fixed designation D2212; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、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.1. Scope1.1 This test method covers the determination of the
3、slit tearresistance of light leathers such as shoe uppers, gloves, andupholstery. This test method does not apply to wet blue.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for informa
4、tion onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, 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
5、 limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1610 Practice for Conditioning Leather and Leather Prod-ucts for TestingD1813 Test Method for Measuring Thickness of LeatherTest SpecimensD2209 Test Method for Tensile Strength of Leather3. Terminology3.1 Definitions:3.1.1 slit te
6、ar resistancethe load required to tear thecross-sectional thickness of the leather at a slit cut through theleather by a die or a sharp knife.4. Significance and Use4.1 This test method is designed to measure the loadrequired to tear leather at a slit cut perpendicular to its surface.Tanners and lea
7、ther buyers have found that it gives anindication of the resistance of the cross-sectional thickness ofleather to tearing. It is of particular value in estimating thedurability of leather to withstand tearing stresses encounteredin the manufacture of shoes, garments, and upholstered prod-ucts. The t
8、hickness of the specimen and direction of slit relativeto the backbone will affect the uniformity of the test results.This test method may not apply when the conditions of the testemployed differ widely from those specified in the test method.5. Apparatus5.1 Testing Machine, as described in Test Met
9、hod D2209.5.2 Thickness GageA dead-weight type of thickness gageas described in Test Method D1813.5.3 Specimen HoldersTwo specimen holders, which arefastened into the jaws of the testing machine and which supportthe specimen during testing (see Fig. 1). The specimen holdersshall be adjusted in the m
10、achine so that they are touching eachother.5.4 DieA die 1 in. (25.4 mm) wide by 2 in. (51 mm) longthat cuts a specimen while simultaneously cutting a slot in thespecimen (see Fig. 2).6. Test Specimens6.1 The specimen shall be 1 by 2 in. (25.4 by 51 mm), cutwith the long dimension either parallel or
11、perpendicular to thebackbone (see Figs. 1 and 2).6.2 The specimen cut with the slit tear die shall have a slot716 in. (0.4375 in. (11 mm) long by316 in. (0.1875 in. (4.8mm) wide tapered with a316-in. radius to a slit at each end ofspecimen as shown in Fig. 2.7. Conditioning7.1 All specimens shall be
12、 conditioned as prescribed inPractice D1610. Conditioning other than as prescribed shall benoted in the results.8. Procedure8.1 Determine the thickness of the specimen to the nearest0.001 in. (0.025 mm) on the long axis at each end of the cut.The gage foot shall be adjacent to, but shall not overlap
13、, thecut.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. (Standard Method E59 1965).Current edition approved
14、 May 1, 2015. Published July 2015. Originally approvedin 1963. Last previous edition approved in 2010 as D2212 00 (2010). DOI:10.1520/D2212-00R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards
15、 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 States18.2 Slip the specimen over the protruding ends of theholders and push it down. The slot cut shall be
16、perpendicular tothe applied force. Run the machine until the specimen is tornapart. Operate at a uniform speed of 10 6 2 in./min (254 6 50mm/min) when running free. Note the maximum load to tearthe specimen.9. Report9.1 The report shall include the following:9.1.1 Thickness to the nearest 0.001 in.
17、(0.025 mm), re-ported for each specimen or averaged and reported as thethickness of the sample,9.1.2 Load in pounds-force (or newtons) to tear the speci-men to the nearest 1 lbf (4.5 N) reported for each specimen oraveraged and reported as the tear resistance of the sample, and9.1.3 Direction of the
18、 long axis of the specimen relative tothe backbone.10. Precision and Bias10.1 The following criteria may be used to judge theacceptability of the results if at least 15 units have been tested:10.1.1 One Operator, Duplicate Specimens, Same SkinResults by the same operator on duplicate adjacent specim
19、ensin a skin taken from the official sampling position should not beconsidered suspect unless the coefficient of variation exceeds:Shoe upper 9Garment 12Upholstery 13CalfskinA7A31oz(8528g),0.0468 0.0156 in. (1.189 0.396 mm).10.1.2 Two Laboratories, Duplicate Specimens, SameSkinResults for the same g
20、roup of light leather listed in10.1.1 submitted by each of two laboratories on duplicateadjacent specimens in a skin taken from the official samplingposition should not be considered suspect unless the twoaverage results differ by more than 5 %.NOTE 1The reproducibility reported in 10.1.2 is based o
21、n dataobtained at two laboratories, each with a different type of testing machineand a different operator. One machine is a load-cell type and the other apendulum type. The results show close correlation between laboratories.NOTE 2The results given in Section 10 are based on tests on 30 sidesof leat
22、her and do not apply to findings and cut parts.NOTE 3The precision data for between skins are not given because theresults were based on different skins of several production lots. Thevariables in leather for between skins will give higher variation of theresults, but this factor should not affect t
23、he precision of the method.11. Keywords11.1 leather; slit tear; slot tear; strength; tear; tear strengthMetric Equivalentsin. mm in. mm in. mm116 1.6 0.266 6.7612 12.70.125 3.27 0.281 7.14 0.812 20.630.187 4.75516 8 1 25.40.197 538 9.5 138 350.219 5.56 0.375 9.53 278 7314 6.4 0.394 10 31116 93FIG. 1
24、 New and Old Style Slit Tear ClampsMetric Equivalentsin.mm3164.81212.758163419125.4251FIG. 2 Shape and Dimensions of Die for Cutting Slit Tear TestSpecimensD2212 00 (2015)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned
25、in this standard. 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 m
26、ust be reviewed 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 t
27、heresponsible technical 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 C7
28、00, West Conshohocken, 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
