关键词: 刃位错, 连分数法, 电子结构, 杂质

Abstract: The atomic structure model of 1/2 [1 1 1] edge dislocation in ferrite phase of steel or iron was set up with computation programmed. The environment-sensitive embedding energy (ESE) and total structure energy of C, N and other alloy elements in grains or in dislocation area were calculated by recursive method separately. The aggregation of and interaction among C, N and alloy elements in dislocation area were discussed. Calculation results showed that the light impurities C and N tend to aggregate at the core of edge dislocation and all the edge dislocations are tied together and can not move freely. The elements Ti, V, Nb and Cr, are formed by strong or moderate carbides and easy to aggregate on the edge dislocation line, but Ni, as not formed by carbides, aggregates in the elastic expansion area below the dislocation line. The light impurities aggravate the aggregation of the elements formed by strong carbides on the edge dislocation lines. Thus, when lowering the temperature the concentrations of C and N and alloy elements exceed the solid solubility limit, and the C and N intermetallic compounds precipitate in the edge dislocation area of ferrite in steel or iron. These compounds will retard the movement of dislocations to cause the strengthening of steel or iron.