高Co-Ni超高强度钢强化析出相的微观分析

摘要

TEM was used to investigate the precipitates in ultra-high strength steel AerMet100 after overaging at 510℃, and the nature of these precipitates was identified by using SAD analysis. The results show that the precipitates are mainly consisted of two types of particles, one is the well-known rod-like M2C carbide with 17.5nm in length and 6nm in diameter, well aligned in the three normal directions which are parallel orientation relationship with martensitic matrix is (011)M//(001)M2C, [100]M//[100]M2C. The other kind of precipitate is ellipsoidal Fe2Mo intermetallic compound (Laves phase) with 11.5nm in diameter, and orientation relationship is (1-12-)M//(001)L, [11-1-]M//[100]L. Both of them are dispersed within the matrix of fine lath martensite and equivalent in size.%使用透射电子显微镜(TEM)观察了高Co-Ni超高强度钢AetMet100在510℃,5h回火后的强化析出相,并利用选区电子衍射方法(SAD)确定了强化相.结果表明,AetMet100钢在超细板条马氏体基体上同时存在两种不同形态的细小强化析出相且尺寸相当:一种是已为很多试验研究所报道过的棒状M2C碳化物,长轴沿基体〈001〉M三个方向互相垂直分布,长度约17.5nm,直径约6nm,与基体的取向关系为(011)M//(001)M2C,[100]M//[100]M2C;另一种是椭球状Fe2Mo金属间化合物(Laves相),直径约11.5nm,与基体的取向关系为(1-12-)M//(001)L,[11-1-]M//[100]L.