1. Have higher high temperature lasting and creep limit andAnd good high temperature fatigue performance.2. Improve the hot strong sexual way(1) increase the Cr, Mo elements such as solid solution strengthening;(2) reduce the S and P content of impurity elements;(3) with B, Ti, Zr in grain boundary strengthening;(4) strengthen by carbide and intermetallic compound dispersoid.3. Hot strong steel type(1) low carbon steel bead light body heat strong(boiler steel)(2) the carbon in the pearl size hot steel(steam turbine rotor steel)(3) strong markov shape hot steel(turbine blade steel(4) heat intensity steel austenite size