三维原子探针对微合金钢中G．P．区的观测

Three dimensional atom probe observation of G.P.zone in micro-alloyed steel

对Nb-V微合金钢进行模拟控轧控冷试验,利用光学显微镜、场离子显微镜、三维原子探针等测试分析技术和手段,研究铁素体基体中碳化物析出早期阶段的特点.用三维原子探针研究基体中碳化物的析出过程,发现在NbC析出初期,C和Nb原子在铁素体同一个(001)原子面上发生偏聚,且质量分数都不到5%,认为这是在基体中形成的G.P.区.

By applying the techniques of optical microscope, field ion microscope （FIM） and three-dimensional atom probe （3 DAP） , the carbides precipitated from ferrite matrix on the early stage of niobium and vanadium micro-alloyed steels were characterized. 3DAP was carried out to investigate the carbides precipitate process in niobium and vanadium micro-alloyed steels. Niobium and carbon atoms segregating at a ferrite matrix （001） plane and the concentration of less than 5% were observed in the matrix during the initial precipitating stages of NbC. The monolayer enrichment zone of niobium and carbon atoms was considered as G.P. zone.