1.1 本规范涵盖通过全熔激光束粉末床熔融（PBF-LB）加工马氏体时效钢合金的零件增材制造。使用这种加工方法制造的零件通常用于需要类似于锻造产品的机械性能的应用中，无论是制造的还是热处理的。根据本规范制造的产品可能需要以机加工、抛光等形式进行额外的后处理，以满足必要的表面光洁度和尺寸要求。 1.2 马氏体时效钢（MS）是一类沉淀硬化钢，其中使用时效热处理来形成沉淀物，从而显著提高硬度和强度。 本规范专门针对300级马氏体时效钢，其对应于UNS K93120和EN1.2709。MS等级300具有比低等级更高浓度的钴和钛。 1.3 本规范适用于额外制造的马氏体时效钢零件的采购商或生产商，或两者兼而有之，以确定要求并确保零件性能。 1.4 建议用户使用本规范作为获得符合委员会成员协商一致制定和修订的最低验收要求的零件的基础。 1.5 可以通过在采购订单中添加一个或多个补充要求来满足被认为更严格的用户要求，这些补充要求包括但不限于第S1至S3节补充要求中列出的要求。 1.6 以国际单位制表示的数值应视为标准。本指南中包含的所有计量单位均可与SI一起使用。 1.7 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。

1.1 This specification covers additive manufacturing of parts via full-melt laser beam powder bed fusion (PBF-LB) processing of maraging steel alloys. Parts made using this processing method are typically used in applications that require mechanical properties similar to wrought products, either as fabricated or heat treated. Products built to this specification may require additional post-processing in the form of machining, polishing, etc., to meet necessary surface finish and dimensional requirements. 1.2 Maraging steel (MS) is a class of precipitation hardened steel, where aging heat treatment is used to form precipitates and, consequently, achieve significantly increased hardness and strength. This specification focuses specifically on 300 grade maraging steel, which corresponds to UNS K93120 and EN1.2709. MS grade 300 has higher concentrations of cobalt and titanium than lower grades. 1.3 This specification is intended for the use of purchasers or producers, or both, of additively manufactured maraging steel parts for defining the requirements and ensuring part properties. 1.4 Users are advised to use this specification as a basis for obtaining parts that will meet the minimum acceptance requirements established and revised by consensus of committee members. 1.5 User requirements considered more stringent may be met by the addition to the purchase order of one or more supplementary requirements, which include, but are not limited to, those listed in Supplementary Requirements in Sections S1 to S3. 1.6 The values stated in SI units are to be regarded as standard. All units of measure included in this guide are accepted for use with the SI. 1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.8 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.