ASTM A959-19

4.1 It is anticipated that the ASTM Subcommittees A01.06, A01.10, A01.17, A01.22, and A01.28 will use the standard composition limits listed in this guide for the grades identified by the corresponding UNS designation in the product specification unless there is a specific technical justification for doing otherwise. The compositions in this guide shall not be considered as chemical requirements for any particular product until adopted by the subcommittee overseeing that product.

4.2 Assuming that uniform compositions among the many product standards for stainless steel are desirable, the composition limits provided in this standard are to be used as guides in determining limits for each of the elements included in the total composition of each grade. The composition limits have been established with the intent that each product subcommittee will find it necessary to require only a minimum number of changes to reflect specific technical effects. Section 5 lists the general guidelines followed for determining the limits for each element; the limits established in this guide are based on these guidelines.

4.3 Not included in this standard stainless steel grade harmonization effort is an attempt to unify stainless steel compositions in ASTM product standards by any means other than recognizing current industry practices.

1.1 This guide provides a guide to ASTM Subcommittees A01.06, A01.10, A01.17, A01.22, and A01.28 for specifying chemical composition limits of wrought stainless steels. It is intended that these recommended grade composition limits be suitable for adoption by other standardization bodies that prepare standards for stainless steel products.

1.2 Included in this guide are the recommendations for determining the number of significant figures for specifying chemical composition from Test Methods, Practices, and Terminology A751.

1.3 All stainless steel UNS numbers and the stainless steel grades in all standards overseen by the aforementioned ASTM subcommittees have been included, except those grades applicable to restricted special end uses and alloys containing less than 10.5 % minimum chromium.

1.4 Not addressed are minor composition modifications which a specific product subcommittee may find necessary to accommodate effects of normal processing or to enhance fabricability by the producer or user, or both.

1.5 Also not generally addressed (except when established by ASTM product subcommittees) is a complete rationalization of all limits, especially when such would conflict with long-standing practices and is not justified by special technical effect.

1.6 Excluded from this guide are cast material and welding filler metal.

1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.