ASTM_B_528_-_16.pdf

Designation:B52816Standard Test Method forTransverse Rupture Strength of Powder Metallurgy(PM)Specimens1This standard is issued under the fixed designation B528;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.1.Scope*1.1 This test method covers determination of the transverserupture strength of sintered,including post-treated,powdermetallurgy test specimens by subjecting them to a uniformlyincreasing transverse force under controlled conditions.Theterm“transverse rupture strength”as used herein,defines thestress,calculated from the flexure formula required to break aspecimen as a simple beam supported near the ends andapplying the force midway between the fixed line center of thesupports.1.2 Limitations The transverse rupture test is only appli-cable to relatively brittle materials.In cases where a ductilespecimen is being tested and the permanent deflection as aresult of testing exceeds 0.02 in.(0.5 mm),the test results maybe questionable.1.3 Test Method B406 should be consulted for determiningthe transverse rupture strength of cemented carbides.1.4 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 not considered standard.1.5 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:2B243 Terminology of Powder MetallurgyB312 Test Method for Green Strength of Specimens Com-pacted from Metal PowdersB406 Test Method for Transverse Rupture Strength of Ce-mented CarbidesB925 Practices for Production and Preparation of PowderMetallurgy(PM)Test SpecimensE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsFor definitions of terms in this test method,see Terminology B243.4.Significance and Use4.1 This test method is used to measure the strength ofsintered,including post-treated,specimens.Transverse rupturestrength is not a design value.For many sintered materials,transverse rupture strength is approximately twice the ultimatetensile strength.5.Apparatus5.1 Micrometer,capable of measuring with a resolution of0.0001 in.(0.002 mm).5.2 Transverse Rupture Strength Fixture,as shown in Fig.1.5.3 Compression Testing Machine,readable to within 0.1%of full scale reading.Use the lowest testing range that canprovide a measurable result.6.Test Specimen6.1 The thin test specimen shall have the shape and dimen-sions shown in the figure titled PM Transverse RuptureStrength Test Specimen of Practices B925.7.Procedure7.1 Prepare test specimens by pressing and sintering usingtooling shown in the figure titled Transverse Rupture TestSpecimen,Typical Laboratory Tooling of Practices B925,ormachine from finished parts.Measure the width and thicknessof the specimens to the nearest 0.001 in.(0.02 mm)with amicrometer.7.2 Locate the specimen in the transverse rupture test fixtureperpendicular to the supporting rods.Apply compressive force1This test method is under the jurisdiction of ASTM Committee B09 on MetalPowders and Metal Powder Products and is the direct responsibility of Subcommit-tee B09.05 on Structural Parts.Current edition approved Oct.1,2016.Published October 2016.Originallyapproved in 1970.Last previous edition approved in 2012 as B528 12.DOI:10.1520/B0528-16.2For 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.*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 parallel to the pressing direction of the specimen at a no-loadcrosshead speed of not greater than 0.2 in./min(5 mm/min)until rupture occurs.Record the load at which the specimenbreaks(force required to rupture specimen,P).8.Calculation8.1 Calculate the transverse rupture strength of the speci-men as follows:TRS53 3P 3L!/2 3T23W!(1)where:TRS=transverse rupture strength of the specimen,psi(MPa),P=force required to rupture the specimen,lbf(N),L=the distance between the centers of the supportingrods,1.000 in.(25.4 mm),W=width of the specimen,in.(mm),andT=thickness of specimen,in.(mm).9.Report9.1 Report the transverse rupture strength as the average ofat least three(3)tests to the nearest 1000 psi(10 MPa).Whenreporting the results,state the following supplementary data toclar