氢与回火脆化对2．25Cr－1Mo钢局部脆断应力的影响

Effects of Hydrogen and Temper Embrittlement on the Local Brittle Fracture Stress of 2.25Cr-1Mo Steels

采用恒温有限元法，研究了一定温度下氢原子与回火脆化对三种不同成分２．２５Ｃｒ－１Ｍｏ钢局部脆断应力的影响。结果发现，可用局部脆断应力σｆ＊的变化衡量材料的回火脆化倾向，但由于晶界上杂质元素与氢原子分布的随机性，可能导致沿晶脆断应力的分散。在降低局部脆断应力的作用上，氢脆与回火脆化具有叠加关系。

Finite element method was employed to investigate the effects of hydrogen atoms and temper embrittlement on the local brittle fracture stress of 2. 25Cr-1Mo steel at a certain low temperature. The results show that the difference of the local brittle fracture stress σf before and after temper embrittlement can be used to judge the temper embrittlement tendency of the steel. However, the random distribution of the impurites and hydrogen atoms at grain boundaries may result in the scatter of the local brittle fracture stress. The superposition relationship between hydrogen and temper embrittlement is also found in decreasing the local brittle fracture stress.