1.1 本规范涵盖用于建筑铆接、螺栓连接或焊接结构以及一般结构用途的结构质量碳锰钢型材、板材和棒材。 1.2 本规范下的材料有两个等级: 等级 屈服强度， ksi[MPa] 厚 50 [345] 50 [345] 板至1英寸。[25毫米]厚 至15英寸。[380毫米]宽 钢筋至3 1. / 2. 在里面[90毫米] 法兰或支腿厚度为 1. 1. / 2. 在里面[40毫米]含 55 [380] 55 [380] 板至1英寸。[25毫米]厚 至15英寸。[380毫米]宽 钢筋至3 在里面[75毫米] 法兰或支腿厚度为 1. 1. / 2. 在里面[40毫米]含 1.3 在焊接钢材时，先决条件是采用适合钢材等级和预期用途或服务的焊接工艺。见规范附录X3 A6/A6M 有关焊接性的信息。 1.4 以英寸为单位的数值- 磅单位或国际单位应视为标准。在文本中，国际单位显示在括号中。每个系统中规定的值不是精确的等价物；因此，每个系统必须相互独立使用。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。

1.1 This specification covers carbon-manganese steel shapes, plates, and bars of structural quality for use in riveted, bolted, or welded construction of buildings and for general structural purposes. 1.2 Material under this specification is available in two grades: Grade Yield Strength, ksi [MPa] Thickness 50 [345] 50 [345] Plates to 1 in. [25 mm] thick to 15 in. [380 mm] wide Bars to 3 1 / 2 in. [90 mm] Shapes with flange or leg thickness to 1 1 / 2 in. [40 mm] inclusive 55 [380] 55 [380] Plates to 1 in. [25 mm] thick to 15 in. [380 mm] wide Bars to 3 in. [75 mm] Shapes with flange or leg thickness to 1 1 / 2 in. [40 mm] inclusive 1.3 When the steel is to be welded, it is presupposed that a welding procedure suitable for the grade of steel and intended use or service will be utilized. See Appendix X3 of Specification A6/A6M for information on weldability. 1.4 The values stated in either inch-pound units or SI units are to be regarded as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. 1.5 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.