ASTM_B_610_-_13.pdf

Designation:B61013Standard Test Method forMeasuring Dimensional Changes Associated withProcessing Metal Powders1This standard is issued under the fixed designation B610;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 standard covers a test method that may be used tomeasure the sum of the changes in dimensions that occur whena metal powder is first compacted into a test specimen and thensintered.1.2 The dimensional change is determined by a quantitativelaboratory procedure in which the arithmetic difference be-tween the dimensions of a die cavity and the dimensions of asintered test specimen produced from that die is calculated andexpressed as a percent growth or shrinkage.1.3 With the exception of the values for density and themass used to determine density,for which the use of the gramper cubic centimetre(g/cm3)and gram(g)units is the long-standing industry practice,the values stated in inch-poundunits are to be regarded as standard.The values given inparentheses are mathematical conversions to SI units that areprovided for information only and are not considered standard.1.4 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:2B215 Practices for Sampling Metal PowdersB243 Terminology of Powder MetallurgyB925 Practices for Production and Preparation of PowderMetallurgy(PM)Test SpecimensB962 Test Methods for Density of Compacted or SinteredPowder Metallurgy(PM)Products Using ArchimedesPrinciple3.Terminology3.1 DefinitionsThe definitions of the Powder Metallurgy(PM)terms that are used in this test method are found inTerminology B243.Additional descriptive information is avail-able in the Related Material section of Vol.02.05 of the AnnualBook of ASTM Standards.4.Summary of Test Method4.1 Rectangular test specimens are compacted to a targetgreen density from a metal powder or metal powder mixtureand sintered under controlled conditions.4.2 The absolute dimensional change,expressed as a growthor shrinkage percentage is calculated from the differencebetween the long dimension of the die cavity and the longdimension of the sintered test specimen.4.3 The comparative dimensional change requires speci-mens from a reference metal powder lot agreed upon by theparties concerned to be produced and processed at the sametime.The dimensional change of the specimens from the testpowder is calculated and mathematically compared with thedimensional change of the specimens from the referencepowder.5.Significance and Use5.1 Dimensional Change When Compacting and SinteringMetal Powders:5.1.1 The dimensional change value obtained under speci-fied conditions of compacting and sintering is a materialcharacteristic inherent in the powder.5.1.2 The test is useful for quality control of the dimensionalchange of a metal powder mixture,to measure compositionaland processing changes and to guide in the production of PMparts.5.1.3 The absolute dimensional change may be used toclassify powders or differentiate one type or grade fromanother,to evaluate additions to a powder mixture or tomeasure process changes,and to guide in the design of tooling.5.1.4 The comparative dimensional change is mainly usedas a quality control test to measure variations between a lot orshipment of metal powder and a reference powder of the samematerial composition.1This test method is under the jurisdiction of ASTM Committee B09 on MetalPowders and Metal Powder Products and is the direct responsibility of Subcom-mittee B09.02 on Base Metal Powders.Current edition approved May 1,2013.Published June 2013.Originallyapproved in 1976.Last previous edition approved in 2008 as B610 08.DOI:10.1520/B0610-13.2For 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 5.1.5 Factors known to affect size change are the base metalpowder grade,type and lot,particle size distribution,level andtypes of additions to the base metal powder,amount and typeof lubricant,green density,as well as processing conditions ofthe test specimen;heating rate,sintering time and temperature,sintering atmosphere,and cooling rate.5.2 Dimensional Change of Various PM Processing Steps:5.2.1 The general procedure of measuring the die or a