晶间脆性断裂的非平衡偏聚机理研究

Nonequilibrium Grain Boundary Segregation Mechanism of Intergranular Embrittlement

中温脆性、回火脆性是困扰材料学界百年的两大晶间脆性难题,其发生机理一直是材料科学与工程学界研究的热点。根据溶质非平衡偏聚恒温动力学特征,总结出了中温脆性的非平衡偏聚机理。另外,依据溶质非平衡偏聚的临界时间现象,综述了回火脆性的非平衡偏聚研究最新进展。通过对以上两种晶间脆性断裂发生机理的分析发现,它们都是由溶质的非平衡偏聚临界时间引起的。

Intermediate temperature embrittlement and temper embrittlement are the problem of intergranular embrittlement which has puzzled the field of materials science and engineering. The mechanisms of these interg- ranular embrittlements have been studied for hundred years. In view of the isothermal kinetics characteristic for NGS, the mechanisms of intermediate temperature embrittlement are discussed. In addition, based on the critical time characteristic, the NGS mechanism of temper embrittlement will be summarized. It is found that intermediate temperature embrittlement and temper embrittlement are induced by the critical time of NGS for solute.