1、Designation: D 6077 00 (Reapproved 2005)Standard Test Method forTrapezoid Tearing Strength of Leather1This standard is issued under the fixed designation D 6077; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revi
2、sion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the measurement of the tearingload of nonwoven fabrics by the trapezoid method for leather.See Test Me
3、thods D 1117. This test method does not apply towet blue.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theres
4、ponsibility 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:2D 1117 Test Methods for Nonwoven FabricsD 1610 Practice for Conditioning Leather and Leath
5、erProducts for Testing3. Summary of Test Method3.1 An outline of a trapezoid (see Fig. 1) is marked on aspecimen cut for the determination of breaking load, and thenonparallel sides of the specimen are clamped in the jaws of atensile testing machine. A continuously increasing load isapplied to the s
6、pecimen in such a way that the tear propagatesacross the specimen width. The value of the breaking load ofthe specimen is obtained from the load-elongation (stress-strain) curve recorded autographically.4. Significance and Use4.1 The trapezoid tearing load is a tension test in which thestrength is d
7、etermined primarily by the fibers of the compositestructure and their bonding or interlocking. It is useful forestimating relative ease of tearing of nonwoven fabrics.4.2 The procedure can also be used to determine if there isany appreciable difference in the relative strength of the fabricin the ma
8、chine and cross-machine directions.5. Apparatus5.1 Tensile Testing Machine, constant-rate-of-traverse type,equipped with an autographic recorder to register the appliedload.5.2 Clamps, with faces measuring 25 by 75 mm (1 by 3 in.)with the longer dimension perpendicular to the direction ofapplication
9、 of the load.5.3 Template, optional, having the dimensions shown in Fig.1.5.4 Pawls, bolt on a machine to allow motion in only onedirection.6. Sampling6.1 Unless otherwise specified, sample as directed, paralleland perpendicular to backbone or parallel and perpendicular tothe cut part.7. Test Specim
10、ens7.1 Unless otherwise specified, test ten specimens.7.2 Cut the test specimens in the machine direction and inthe cross-machine direction.8. Conditioning8.1 Condition the test specimens for 24 h at 21 6 2C (706 2F) and 50 6 5 % relative humidity or in accordance withPractice D 1610. (The customer
11、may specify.)9. Procedure9.1 Test properly conditioned test specimens in the standardatmosphere for testing.9.2 Set the clamps at the start of the test 25 6 1mm(160.05 in.) apart and operate the machine at 300 6 10 mm (12 60.40 in.)/min. Select the load range of the testing machine suchthat the brea
12、k occurs between 10 and 90 % of the full-scaleload.9.3 Secure the test specimen in the machine, clamping alongthe nonparallel sides of the trapezoid with the cut halfwaybetween the clamps. Hold the short edge taut and let the longedge lie in folds.1This test method is under the jurisdiction of ASTM
13、Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.05 on Upholstery.Current edition approved Sept. 1, 2005. Published September 2005. Originallyapproved in 1997. Last previous edition approved in 2000 as D 6077 - 00.2For referenced ASTM standards, visit the ASTM website, ww
14、w.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.9.4
15、Start the machine with pawls disengaged, and record thetearing load on the autographic recorder. The tearing load willnot be a single value, but will appear as a series of maxima andminima.10. Calculation10.1 Visually fit a straight line parallel to the elongation axisthrough the maxima, and use thi
16、s as the maximum load. Repeatthis for the minima. Take the average of these two values as thetearing load for that specimen.10.2 Separately calculate the average of the tearing load ofthe five machine direction test specimens and the average ofthe five cross-machine direction specimens.11. Report11.
17、1 Report the following information:11.1.1 Test specimens were tested in accordance with TestMethods D 1117,11.1.2 Describe the material or product samples, and11.1.3 Describe the method of sampling used.12. Precision and Bias12.1 PrecisionA coefficient of variation of about 5 % canbe anticipated.12.
18、2 BiasThe true value of the trapezoid tearing strengthcan be defined only in terms of a specific test method. Withinthis limitation, the procedure for testing trapezoid tearingstrength has no known bias.13. Keywords13.1 tear strength; tearing load; template; tension test;trapezoidASTM International
19、takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin 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
20、 responsibility.This standard is subject to revision at any time by the responsible technical committee and must 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 add
21、ressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible 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
22、 the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, 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).FIG. 1 Template for Trapezoid Tearing Load TestD 6077 00 (2005)2
