Research on Physical Significance of the Larson-Miller Parameter and Its Electron Theory for Heat-Resistant Steels

摘要

The Larson-Miller parameter (LMP=T(C+log t)) with the determined C-value is suitable to describe the high-temperature ageing behaviour of pearlitic heat resistant steels, such as 12Cr1MoV with C of 20.62, and 15CrMo 20.30. The heat strength parameter Pc was proposed as one property of materials, and heat processing factor P as temperature-time processing parameter. In addition, the relationship between Pc and P was discussed. Then, based on the calculation of valence electron structures by the Empirical Electron Theory of Solid and Molecules (EET), the physical nature and microscopic meaning of C constant in LMP were analyzed, including the effects of carbon content on C-value.