ASTM_A_959-19.pdf

4A959-19martensitic in structure and hardenable by precipitation hard-lower limit for specific technical effect.Exception-some ofening(sometimes called age hardening).the Cr-Ni-Mn austenitic grades have always been produced to3.1.6 standard stainless steel grade,n-listed chemical0.060 position associated with a stainless steel grade identified5.4 Sulfur-It is recommended that 0.030 maximum beby a particular UNS number appearing in SAE publicationapplied to all grades except the free-machining grades unlessHS-1086,except as modified by an ASTM subcommitteelower limits have been required for specific technical effects.having oversight of a wrought stainless steel product where5.5 Silicon-Past practice has been to establish 0.75such a modification is justified by a specific technical effect.maximum for tubular related products such as flat rolled and4.Significance and Usetubulars,and 1.00%maximum for long products and forgings.For grades produced both as long and flat-rolled products,I%4.1 It is anticipated that the ASTM Subcommittees A01.06.maximum was chosen since it will also include productsA01.10.A01.17.A01.22.and A01.28 will use the standardmelted to lower limits.Use of lower or higher limits should becomposition limits listed in this guide for the grades identifiedbased on specific technical effect.by the corresponding UNS designation in the product specifi-cation unless there is a specific technical justification for doing5.6 Chromium-A composition spread of 2 is recom-otherwise.The compositions in this guide shall not be consid-mended;existing broader limits were not reduced to less thanered as chemical requirements for any particular product untila 3 spread.adopted by the subcommittee overseeing that product.5.7 Nickel-It is recommended that the composition spread4.2 Assuming that uniform compositions among the manynot exceed 3%unless a broader(generally higher)spread isproduct standards for stainless steel are desirable,the compo-justified by specific technical effect.sition limits provided in this standard are to be used as guides5.8 Molybdenum-It is recommended that the compositionin determining limits for each of the elements included in thespread not exceed 1%unless a broader range is justified bytotal composition of each grade.The composition limits havespecific technical effect.Molybdenum limits having only abeen established with the intent that each product subcommit-maximum limit but no minimum should not be used unlesstee will find it necessary to require only a minimum number ofjustified by specific technical effect.changes to reflect specific technical effects.Section 5 lists the5.9 Nitrogen-It is recommended that nitrogen limits havinggeneral guidelines followed for determining the limits for eachonly a maximum limit but no minimum should not be usedelement:the limits established in this guide are based on theseunless justified by specific technical effect.guidelines.5.10 Copper-It is recommended that copper limits having4.3 Not included in this standard stainless steel gradeonly a maximum limit but no minimum should not be usedharmonization effort is an attempt to unify stainless steelunless justified by specific technical positions in ASTM product standards by any means otherthan recognizing current industry practices.5.11 Columbium and Tantalum-Except for special applica-tions requiring positive identification of tantalum,it is recom-5.General Guidelines Used for Determining Compositionmended that prior listings of these two elements together beLimitslimited to listing only columbium.The words columbium5.1 Carbon-It is recommended that limits be to only twoand niobiumrefer to the same element.decimal places for levels of 0.04 and higher because it is not6.Harmonized Standard Grade Stainless Steelnecessary to control to such precision at levels above 0.04%Compositions(It should be recognized that limits such as 0.045 maximummay also be simply stated as 0.04%maximum.)It is also6.1 The harmonized composition limits are shown in Table1,grouped by metallurgical classification.that is.austenitic.recommended that three decimal places be used at levels of0.030 and lower,unless,for example,it is clearly recognizedaustenitic-ferritic,and so forth.Within those groups,grades arethat 0.03%maximum means that 0.035 is satisfactory.listed by UNS designation,in numerical order.5.2 Manganese-Except for the Cr-Ni-Mn grades6.2 Unless adopted by the appropriate product subcommit-(S2XXXX).it is recommended that limits of 2 maximumtee in a product standard,the compositions described in thisand 1 maximum be used for the austenitic and other gradesguide shall not be used for specifying an ASTM product.respectively.except for the free machining grades with high7.Keywordssulfur or selenium,or when necessary to promote nitrogen7.1 austenitic stainless steels;austenitic-ferritic or ferritic-solubility.austenitic stainless steels;duplex stainless steels;ferritic stain-5.3 Phosphorus-It is recommended that 0.045 maxi-less steels;harmonized stainless steel compositions;marten-mum be applied to austenitic grades,and 0.040 maximum tositic stainless steels;precipitation hardening stainless steels;other grades unless the sponsoring producer recommends astandard stainless steel grade compositions24A959-190P.0-0-0mN06.0-01031080000800-0000080-2OM.:070008058800804.0-000070-060100.0-80000006021028002011002p0.号81:0-0001020588.000.:00:0000品0/-05品820-22-006-0420-08品8T0261-0.02820品品6-0.3品2008L-091002-0R200b的8品8888bb888888888888800538888888888878888888800888号8号81888888030333883808330888昌8昌器8909-0P监良2金月3838838383888888888888191:01100888胃器麦妾妾妾复4A959-1951-000M0007600000.:,;.05011.10MP0000mm152-001M80-0605.60美00A959-19.2.01.0.0.0408208.:SEO IV0-0.-000mm8620855SEOIV000.0:09O-SLOSNn