BS 970的本部分适用于直接硬化变形合金钢，适用于热处理条件，以提供35-100 tonf/in2的最小抗拉强度，用于铸坯、坯料、棒材和锻件。包括能够通过渗氮进行表面硬化的钢。第4节中规定了6英寸以下的大多数钢和10英寸以下的某些选定钢的机械性能。购买本文件时可获得的所有当前修订均包含在购买本文件中。

This Part of BS 970 applies to direct hardening wrought alloy steels, suitable in the heat treated condition, to give minimum tensile strengths of 35-100 tonf/in2for use in the form of blooms, billets, bars and forgings. Steels capable of surface hardening by nitriding are included. Mechanical properties are specified in Section 4 for most of the steels for ruling sections up to 6 in and for certain selected steels up to 10 in.All current amendments available at time of purchase are included with the purchase of this document.