The Development of Materials of Supercritical Units or Ultra Supercritical Units

Supercritical units or ultra supercritical units are the future trend of the fossil power plant in China. One of the key points to develop supercritical units or ultra supercritical units is the development of the high-temperature component materials. The paper introduces the developmental history, the status and the future tendency in developed countries, such as America, Japan and Europe. The progresses have established a base for the further development of steam turbine unit at 650℃. Through analysis, some measures of improving material properties at high temperature have been pointed out. They are: (1) optimizing chemical contents can improve the structure stability of high-temperature component material; (2)optimizing chemical contents can improve the fatigue properties;(3)adopting the advanced smelt technology such as VCD、ESR can keep the impurities at lowest level, and this can enhance the general high-temperature properties.