摘要
采用X射线衍射技术测定了GH4169合金中δ相在900℃、930℃时的析出动力学,并采用光学显微镜进行组织观察,结果表明:δ相的形核位置和形核方式与时效温度有关.当时效温度在900℃时,δ相主要在晶界和孪晶界上形核析出,而晶内颗粒状δ相由时效初期析出的亚稳态γ″相转变形成;当时效温度为930℃时,δ相不仅可以在晶界和孪晶界形核析出,还可以从基体γ莫直接形核析出,并且随着时效时间的延长,δ相逐渐向晶内生长,最终形成魏氏体δ相.当时效温度一定时,δ相的析出含量与时效时间满足Avram i方程.
X-ray diffraction and optical microscopy were used to analyze the precipitation kinetics and microstructure evolution of δ-phase in GH4169 alloy at 900℃ and 930℃.The results indicate that the sites and modes of δ-phase＇s nucleation were related to aging temperature.At 900℃,δ-phase mainly precipitated in the grain and twin grain boundaries,intragranular δ-phase was found to be derived from the mestastable γ″ phase in both grain and grain boundaries.At 930℃,δ-phase precipitated in the grain and twin grain boundaries.Also,δ-phase was found to precipitate from the γ matrix.With the increase of the aging time,delta phase grew into grains,and finally transformed into widmanstatten δ-phase.At a given aging temperature,the relationship between the precipitation content of δ-phase and aging time follows Avrami equation.
出处
《沈阳理工大学学报》
CAS
2010年第2期23-26,共4页
Journal of Shenyang Ligong University
基金
国家自然科学基金重点项目(50834008)
国家973项目(2010CB631200-G)
