ASTM_A_890_-_A_890M_-_13.pdf

Designation:A890/A890M13Standard Specification forCastings,Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant,Duplex(Austenitic/Ferritic)for GeneralApplication1This standard is issued under the fixed designation A890/A890M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This specification covers a group of cast duplex stainlesssteels(austenitic/ferritic).1.2 The duplex stainless steel alloys offer a combination ofenhanced mechanical properties and corrosion resistance whenproperly balanced in composition and properly heat treated.Ferrite levels are not specified,but these alloys will develop arange of approximately 30 to 60%ferrite with the balanceaustenite.It is the responsibility of the purchaser to determinewhich grade shall be furnished depending on design andservice conditions,mechanical properties,and corrosion-resistant characteristics.NOTE1Because of the possibility of precipitation of embrittlingphases,the grades included in this specification are not recommended forservice at temperatures above 600F 315C.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.3.1 Within the text,the SI units are shown in brackets.2.Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA732/A732M Specification for Castings,Investment,Car-bon and Low Alloy Steel for General Application,andCobalt Alloy for High Strength at Elevated TemperaturesA781/A781M Specification for Castings,Steel and Alloy,Common Requirements,for General Industrial UseE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE562 Test Method for Determining Volume Fraction bySystematic Manual Point CountE1245 Practice for Determining the Inclusion or Second-Phase Constituent Content of Metals by Automatic ImageAnalysis3.Ordering Information3.1 Orders for material to this specification shall include thefollowing,as required,to describe the material adequately:3.1.1 Description of casting by pattern or drawing number(dimensional tolerance shall be included on the castingdrawing),3.1.2 Specification designation and grade including year ofissue,3.1.3 Options in the specification(See 9.1),and3.1.4 Supplementary requirements desired,including thestandards of acceptance.4.Process4.1 The steel shall be made by the electric furnace processwith or without separate refining such as argon-oxygen-decarburization(AOD).5.Heat Treatment5.1 Castings shall be heat treated in accordance with therequirements in Table 1.NOTE2Proper heat treatment of these alloys is usually necessary toenhance corrosion resistance and in some cases to meet mechanicalproperties.Minimum heat-treat temperatures are specified;however,it issometimes necessary to heat-treat at higher temperatures,hold for someminimum time at temperature and then rapidly cool the castings in orderto enhance the corrosion resistance and meet mechanical properties.6.Chemical Composition6.1 The steel shall conform to the requirements as tochemical composition prescribed in Table 2.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloysand is the direct responsibility of SubcommitteeA01.18 on Castings.Current edition approved Dec.1,2013.Published December 2013.Originallyapproved in 1988.Last previous edition approved in 2012 as A890/A890M 12a.DOI:10.1520/A0890_A0890M-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 7.General Requirements7.1 Material furnished to this specification shall conform tothe requirements of Specification A781/A781M,including anysupplementary requirements that are indicated in the purchaseorder.Failure to comply with the general requirements ofSpecification A781/A781M constitutes nonconformance withthis specification.In case of conflict between the requirementsof this specification and Specification A781/A781M,thisspecification shall prevail.8.Repair by Welding8.1 The composition of the deposited weld metal may besimilar to that of the casting or may be suitably alloyed toachieve the desired corrosion resistance and mechanical prop-erties.8.2 Weld repairs shall be subject