ASTM_B_715_-_96_2001.pdf

Designation:B 715 96(Reapproved 2001)Standard Specification forSintered Copper Structural Parts for Electrical ConductivityApplications1This standard is issued under the fixed designation B 715;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers sintered Powder Metal(P/M)structural parts of substantially pure copper of two typesdepending on density.It is anticipated that the parts will beused in applications where high electrical conductivity isrequired.1.2 The values stated in inch-pound units are the standard.The SI values in parentheses are for information only and maybe approximate.2.Referenced Documents2.1 ASTM Standards:B 243 Terminology of Powder Metallurgy2B 328 Test Method for Density,Oil Content,and Intercon-nected Porosity of Sintered Powder Metal Structural Partsand Oil-Impregnated Bearings2E 8 Test Methods of Tension Testing of Metallic Materials33.Terminology3.1 DefinitionsDefinitions of powder metallurgy termscan be found in Terminology B 243.Additional descriptiveinformation is available in the Related Materials section of Vol02.05 of the Annual Book of ASTM Standards.4.Ordering Information4.1 Orders for parts under this specification shall include thefollowing information:4.1.1 Dimensions(see Section 9),4.1.2 Chemical composition(see 6.1 and Table 1),4.1.3 Density(see 7.1 and Table 2),4.1.4 Mechanical properties(see Section 8),4.1.5 Electrical properties(see 7.2),4.1.6 Certification(see Section 13),and4.1.7 Metallography(see Section 14).5.Materials and Manufacture5.1 Structural parts shall be made by molding and sinteringmetal powders followed by repressing and resintering,ifnecessary,to produce finished parts conforming to the require-ments of this specification.6.Chemical Composition6.1 The material shall conform to the requirements in Table1.6.2The chemical analysis shall be made in accordancewith the methods prescribed in Vol 03.05 of the Annual Bookof ASTM Standards,or by any other approved method agreedupon between the manufacturer and the purchaser.NOTE1Iron contamination should be avoided.Iron in solid solutionin copper has a deleterious effect on both electrical and thermal conduc-tivity.Iron not in solid solution(admixed)has a much lesser effect onconductivity.An example of the effect of iron on conductivity is shown inFig.X1.1 appended.7.Physical Properties7.1 Density:7.1.1 The density shall be determined by Test MethodB 328.If the density does not vary more than 0.3 g/cm3fromone section of the structural part to any other section,theoverall density shall fall within the limits prescribed in Table 2.If the density varies more than 0.3 g/cm3from one section ofthe part to another,the manufacturer and the purchaser shallagree upon a critical section of the part where the stresses arehighest.The density of this critical section,rather than theaverage density,shall fall within the limits prescribed in Table2.1This specification is under the jurisdiction of ASTM Committee B09 on MetalPowders and Metal Powder Products and is the direct responsibility of Subcom-mittee B09.05 on Structural Parts.Current edition approved March 10,1996.Published May 1996.Originallypublished as B 715 83.Last previous edition B 715 83(89).2Annual Book of ASTM Standards,Vol 02.05.3Annual Book of ASTM Standards,Vol 03.01.TABLE 1 Chemical RequirementsElementComposition,%Copper,min99.80Other,max0.20TABLE 2 Density RequirementsTypeDry Density,g/cm3I7.8 to 8.3II8.3 min1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.7.2 Electrical Conductivity:7.2.1 The manufacturer and the purchaser shall agree onqualification tests to determine the electrical conductivity.4Thetest shall be made on sample parts or specimens molded to agiven density using an apparatus based on the eddy-currentprinciple.7.2.1.1 Conductivity is determined with an instrument thatindicates the resistance of a material to the flow of eddycurrents.Prior to making the tests,the instrument is allowed towarm up for a period of time recommended by the manufac-turer.The instrument is adjusted using three standards ofknown conductivity supplied by the manufacturer.Test speci-mens must be at the same temperature as the referencematerials used in adjusting the instrument.Several readings atdifferent locations are taken on each test specimen to obtain arepresentative average value.7.2.1.2 No specimen preparation is required providing thesurface is flat in the probe area.7.2.1.3 Electrical conductivity values shall be reported inpercent IACS(International Annealed Copper Standards).NOTE2Typical electrical conductivity values which may be expectedfrom special specimens molded to size are given in Table X1.1.8.Mechanical Properties8