1、Designation:A60294(Reapproved 2014)Standard Specification forAutomotive Malleable Iron Castings1This standard is issued under the fixed designation A602;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A numb
2、er in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers castings of ferritic,pearlitic,tempered pearlitic,and tempered martensitic grades of mal-leable iron used in the prod
3、ucts of the automotive and alliedindustries.Castings shall be heat treated to meet this specifi-cation.1.2 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 con
4、sidered standard.2.Referenced Documents2.1 ASTM Standards:2E10 Test Method for Brinell Hardness of Metallic Materials3.Grades3.1 The specified grades with required hardness range andfinal heat treatment are shown in Table 1.3.2 The foundry may also produce Grades M4504 andM5003 by liquid quenching a
5、nd tempering or alloying,or both.4.Hardness4.1 The foundry shall exercise the necessary controls andinspection procedures to ensure compliance with the specifiedhardness range.Hardness readings shall be taken in accordancewith Test Method E10 after sufficient material has beenremoved from the castin
6、g surface to ensure representativehardness readings.The area or areas on the casting wherehardness is to be checked shall be established by agreementbetween supplier and purchaser and shown on the drawing.5.Microstructure Requirements5.1 Grade M3210 Ferritic Malleable Iron:5.1.1 The microstructure o
7、f Grade M3210 malleable ironshall consist of temper-carbon nodules distributed in a matrixof ferrite.5.1.2 Because of reaction with the annealing furnaceatmosphere,some depletion of carbon and silicon occurs at thesurface of the castings.This usually results in a rim which canconsist of coarse lamel
8、lar pearlite underlying a graphite-freeferritic surface layer.If the pearlite layer is excessive,it canresult in poor machinability.The rim,therefore,shall notexceed a depth greater than 0.050 in.(1.27 mm)as measuredfrom the casting surface.5.1.3 The area below the rim can contain some pearlite;howe
9、ver,it shall not exceed the amount shown in Fig.1.5.2 Grades M4504,M5003,M7002,and M8501:5.2.1 The microstructure of these other grades of malleableiron shall consist of temper-carbon nodules distributed in amatrix of ferrite and lamellar pearlite or tempered pearlite inair-quenched castings or a ma
10、trix of tempered martensite in thecase of liquid-quenched castings.5.2.2 Because of reaction with the annealing furnaceatmosphere,some depletion of carbon and silicon occurs at thesurface of the castings.This usually results in a rim which canconsist of a graphite-free layer sometimes containing mor
11、e orless combined carbon than the underlying material.5.3 All grades shall be free of primary graphite.5.4 All grades shall not exceed 2%spheroidal primarycarbides in the microstructure.5.5 The maximum surface ferrite layer and denodularizedzone shall be measured after polishing,etching in nital,and
12、viewing at 100.6.Quality Assurance6.1 Sampling plans are a matter of agreement betweensupplier and purchaser.The supplier shall employ adequateequipment and controls to ensure that parts conform to theagreed upon requirements.7.General7.1 Castings furnished to this specification shall be repre-senta
13、tive of good foundry practice and shall conform todimensions and tolerances specified on the casting drawing.1This specification is under the jurisdiction of ASTM Committee A04 on IronCastings and is the direct responsibility of Subcommittee A04.02 on Malleable andDuctile Iron Castings.Current editi
14、on approved April 1,2014.Published April 2014.Originallyapproved in 1970.Last previous edition approved in 2009 as A602 94(2009).DOI:10.1520/A0602-94R14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStanda
15、rds volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.2 Minor imperfections usually not associated with thestructural function may occur in castings.These
16、imperfectionsoften are repairable;however,repairs shall be made only inareas allowed by the purchaser and only by approved methods.7.3 Additional casting requirements may be agreed uponbetween the purchaser and supplier.These should appear asadditional product requirements on the casting drawing.8.Keywords8.1 casting;ferrite;malleable iron;mechanical properties;pearlite;temper carbon nodules;tensile strength;yield strengthAPPENDIX(Nonmandatory Information)X1.MATERIAL DESCRIPTION OF MALLEABLE IRO
