镍基高温合金GH4282的凝固和偏析行为  

Solidification and Segregation Behavior of Nickel-Based Superalloy GH4282

作　　者：颜晓峰 董建新[1] 石照夏[2] 段春华[2] Yan Xiaofeng;Dong Jianxin;Shi Zhaoxia;Duan Chunhua(University of Science and Technology Beijing,Beijing 100083,China;Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]北京科技大学,北京100083 [2]钢铁研究总院,北京100081

出　　处：《稀有金属材料与工程》2019年第10期3183-3189,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51601041)

摘　　要：采用差示扫描量热(DSC)分析、显微组织观察和热力学计算相结合的方法对镍基高温合金GH4282的凝固过程和元素偏析行为进行研究,得到了合金的凝固顺序以及元素偏析特征。结果表明,GH4282合金的凝固顺序为:γ基体、MC碳化物以及少量的硼化物。由DSC测得的GH4282合金的固-液相温度范围为1316~1367℃,MC型碳化物的溶解温度为1338℃。热力学计算结果表明,GH4282合金在凝固过程中,C、B、Ti和Mo偏聚于枝晶间,Al偏析于枝晶干,Cr、Fe和Co几乎不发生偏析,这与铸态组织观察到的元素偏析特征是一致的。The solidification process and the segregation behavior of the elements of GH4282 superalloy were investigated by a combination of differential scanning calorimeter(DSC),microstructure observation and thermodynamic calculation.The solidification sequence and the characteristics of elements segregation were obtained.The results show that the solidification sequence of GH4282 is as follows :γ matrix,MC carbide and a small amount of boride.The solidus-liquidus temperature range determined by DSC is 1316~1367 ℃.The measured solvus temperature of MC carbide is 1338 ℃.Thermodynamic calculations show that C,B,Ti and Mo segregate to the interdendritic regions,while Al segregates to the dendrite cores.Cr,Fe and Co do not exhibit any significant tendency to segregate to either the interdendritic region or to the dendrite core during the solidification process of GH4282 superalloy.These results about segregation behavior of the elements agree well with the as-cast microstructure observation.

关 键 词：镍基高温合金 GH4282 凝固 偏析 

分 类 号：TG146.15[一般工业技术—材料科学与工程] TG111.4[金属学及工艺—金属材料]