Cu对K4169合金凝固过程及凝固偏析的影响  

Effect of Copper on Solidification Process and Segregation in K4169 Superalloy

作　　者：李亚敏[1] 胡伟[1] 陈毅[1] 

机构地区：[1]兰州理工大学有色金属合金及加工教育部重点实验室

出　　处：《特种铸造及有色合金》2013年第10期895-898,共4页Special Casting & Nonferrous Alloys

基　　金：甘肃省自然科学基金资助项目(1112RJZA030)

摘　　要：利用手工电弧炉熔炼制备了Cu含量为O～0．5％的K4169合金，并采用X射线衍射、金相显微镜、扫描电镜、能谱仪以及差热分析，对合金的相组成、凝固组织、元素偏析及熔点进行了研究。结果表明，Cu是负偏析元素，主要富集于枝晶臂上；Cu的加入促进了合金中Nb、Mo、Fe等元素的偏析，使铸态合金晶界析出的Laves相和碳化物数量增多；同时Cu的加入降低了Laves相初熔温度与合金的熔点。分析认为，Cu对K4169合金凝固组织不利。K4169 superalloy with different Cu contents from 0 to 0.5% （weight percentage） was prepared by a manual electric arc furnace. The phase composition, solidification structure, segregation and the melting point of the superalloy prepared were observed by XRD （X-ray diffraction）, OM （optical micro- scope）, SEM （scanning electron microscope）, SEM-EDS and DSC. The results show that Cu is negative segregation element which mainly enriched at the dendrite arm, and it promotes the segregation of Nb, Mo and Fe, meanwhile, Cu promotes significantly the precipitation of Laves phase and MC carbide at the grain boundaries. In addition, the incipient melting temperature of Laves phase and the melting point of alloy are decreased with the Cu addition. The analysis shows that Cu is harmful to the solidifica- tion structure of K4169 superalloy.

关 键 词：K4169合金 CU 凝固组织 元素偏析 LAVES相 

分 类 号：TG244.3[金属学及工艺—铸造]