ASTM_B_593_-_96_2014e1.pdf

Designation:B59396(Reapproved 2014)1Standard Test Method forBending Fatigue Testing for Copper-Alloy Spring Materials1This standard is issued under the fixed designation B593;the number immediately following the designation indicates the year oforiginal adoption or,in the case 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.1NOTEEditorial changes were made in Sections 1.1,1.2,3.1 and 3.2 in September 2014.1.Scope*1.1 This test method establishes procedures for the determi-nation of the reversed or repeated bending fatigue properties ofcopper alloy flat-sheet or strip-spring materials by fixedcantilever,constant deflection(that is,constant amplitude ofdisplacement)-type testing machines.This method is limited toflat stock ranging in thickness from 0.005 to 0.062 in.(0.13 to1.57 mm),to a fatigue-life range of 105to 108cycles,and toconditions where no significant change in stress-strain relationsoccurs during the test.NOTE1This implies that the load-deflection characteristics of thematerial do not change as a function of the number of cycles within theprecision of measurement.There is no significant cyclic hardening orsoftening.1.2 UnitsThe values stated in inch-pound units are to beregarded as standard.Values given in parentheses are math-ematical conversions to SI units which are provided forinformation only and are not considered standard.1.3 The following safety hazard caveat pertains only to thetest methods(s)described in this test method.1.3.1 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 to use.2.Referenced Documents2.1 ASTM Standards:2B846 Terminology for Copper and Copper AlloysB950 Guide for Editorial Procedures and Form of ProductSpecifications for Copper and Copper AlloysE206 Definitions of Terms Relating to Fatigue Testing andthe Statistical Analysis of Fatigue Data;Replaced byE 1150(Withdrawn 1988)3E468 Practice for Presentation of Constant Amplitude Fa-tigue Test Results for Metallic Materials2.2 Other ASTM Documents:4ASTM STP 91-A3.Terminology3.1 For definition of terms relating to this test method,referto Definitions E206 and Practice E468.3.2 For definitions of terms related to copper and copperalloys,refer to Terminology B846.4.Summary of Test Method4.1 A prepared test specimen of a specific wrought copperalloy flat-sheet or strip-spring material is mounted into a fixedcantilever,constant-deflection type fatigue testing machine.The specimen is held at one end,acting as a cantilever beam,and cycled by flexure followed by reverse flexure untilcomplete failure.The number of cycles to failure is recorded asa measure of fatigue-life.5.Significance and Use5.1 The bending fatigue test described in this test methodprovides information on the ability of a copper alloy flat-springmaterial to resist the development of cracks or general me-chanical deterioration as a result of a relatively large number ofcycles(generally in the range 105to 108)under conditions ofconstant displacement.5.2 This test method is primarily a research and develop-ment tool which may be used to determine the effect ofvariations in materials on fatigue strength and also to provide1This test method is under the jurisdiction of ASTM Committee B05 on Copperand Copper Alloys and is the direct responsibility of Subcommittee B05.06 onMethods of Test.Current edition approved Sept.1,2014.Published September 2014.Originallyapproved in 1973.Last previous edition approved in 2009 as B593 96(2009)1.DOI:10.1520/B0593-96R14E01.2For 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 ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4For referenced ASTM documents,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 data for use in selecting copper alloy spring materials forservice under conditions of repeated strain cycling.5.3 The results are suitable for direct application in designonly when all design factors such as loading,geometry of part,frequency of straining,and environmental conditions areknown.The test method is generally unsuitable for an inspec-tion test or a quality control test due to the amount of time andeffort required to collect the data.6.Apparatus6.1 Testing MachineTh