1、Designation:D221200(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 number
2、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 slit tearres
3、istance 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 information onlyand are
4、 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 limitations prior
5、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 tear resistancethe load
6、 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 leather buyers have found
7、 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 thickness of the specimen a
8、nd 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 Method D2209.5.2 Thickness Gage
9、A 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 machine so that they are touching
10、 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 perpendicular to thebackbone(see Figs.1 a
11、nd 2).6.2 The specimen cut with the slit tear die shall have a slot716in.(0.4375 in.(11 mm)long by316in.(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 conditioned as prescribed inPractice D1610.Conditioni
12、ng 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,thecut.1This test method is under the jurisdiction of ASTM
13、 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 May 1,2015.Published July 2015.Originally approvedin 1963.La
14、st 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 volume information,refer to the standards Document Summary page onthe
15、ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 8.2 Slip the specimen over the protruding ends of theholders and push it down.The slot cut shall be perpendicular tothe applied force.Run the machine until the specimen is torna
16、part.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.(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 Direct
