一、前言我国电力工业正进入世界先进水平的行列,对动力装置使用的材料,提出了更高的要求。螺栓钢是超临界参数汽轮机组的关键材料之一,在565—600℃温度范围内,国外是采用变性12％铬钢和高铬镍奥氏体钢,如苏联在K—300—240型30万汽轮机组使用的螺栓钢是变性12％铬钢 I. Preface China’s power industry is entering the ranks of the world’s advanced level, put forward higher requirements on the materials used in power plant. Bolt steel is one of the key materials for supercritical steam turbine. In the temperature range of 565-600 ℃, denatured 12% chromium steel and high-chromium nickel austenitic steel are used in foreign countries. For example, in the Soviet Union, the K-300-240 300,000 steam turbine Bolt steel used in the group is denatured 12% chromium steel