摘要
利用螺旋选晶法制备了镍基单晶合金,研究了热处理过程中合金的组织演变。结果表明:合金的铸态组织由枝晶组成,W偏析于枝晶干,Ti、Cr、Mo和Ta偏析于枝晶间,固溶处理可以消除铸态组织中的枝晶,减小成分偏析,固溶温度越高,粗大的γ'和γ/γ'共晶溶解的越完全。时效处理过程中,大尺寸的γ'发生粗化,小尺寸的γ'逐渐消失,时效温度越高,γ'粗化得越严重。热处理促进合金元素在γ和γ'中的均匀分布,减小了合金的错配度。
A Ni-based superalloy was prepared by screw selecting crystal method.Microstructure evolution of the alloy during heat-treatment was investigated.The results show that the as-casting microstructure is composed by dendrites.EDS analysis indicates that W partitioned in dendrite zone and Ti,Cr,Mo,Ta in inter-dendrite.Solid solution treatment decreases composition partitioning,and with the increase of the solution temperature,coarsening γ＇ and γ/γ＇ eutectic solves completely.During the aging treating,the larger γ＇ coarsenes and the smaller γ＇ disappeares gradually.Mismatch of the alloy decreases after heat-treating which due to the elements diffusing caused by heat-treatment.
出处
《热加工工艺》
CSCD
北大核心
2012年第2期214-218,共5页
Hot Working Technology
关键词
镍基单晶合金
枝晶
固溶
时效
错配度
Ni-base single crystal superalloy
dendrite
solid solution
aging
mismatch
