原位观察镍基高温合金CMSX-4缩松形成过程及机理研究  

In-situ Observation of Shrinkage Formation and Its Mechanism During Ni-based CMSX-CMSX-4 Superalloy Solidification

作　　者：许桐舟 潘秀红[2] 张明辉[2] 汤美波[2] 李会东 刘学超[2] Xu Tongzhou;Pan Xiuhong;Zhang Minghui;Tang Meibo;Li Huidong;Liu Xuechao(Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China;China Innovation Academy of Intelligent Equipment Co.,Ltd,Ningbo 315700,China)

机构地区：[1]中国科学院上海硅酸盐研究所晶体中心,上海200050 [2]中国科学院上海硅酸盐研究所,上海200050 [3]中机智能装备创新研究院(宁波)有限公司,浙江宁波315700

出　　处：《稀有金属材料与工程》2021年第4期1113-1117,共5页Rare Metal Materials and Engineering

基　　金：Ministry of Major Science&Technology of Shanghai(19DZ1100703);National Natural Science Foundation of China(51472263);Shanghai Institute of Ceramics,Chinese Academy of Sciences Launched the Fund in Advance(Y82ZC8180G);Key Laboratory of Space Manufacturing,Chinese Academy of Sciences(SMT-2019-004)。

摘　　要：采用共聚焦激光扫描显微镜(CLSM)对镍基单晶高温合金CMSX-4的凝固行为进行实时观察。并利用扫描电镜(SEM)和能谱仪(EDS)对凝固样品的微观形貌和元素偏析特性进行研究。结果表明,在合金凝固过程中观察到缩松和碳化物的形成。缩松具有3种形态:方形缩松,五角星形缩松和角形缩松。并讨论了3种缩松的形成机理,缩松的形成机制主要与次级枝晶臂沿不同方向生长所包围的封闭区域的形状有关。另外,发现碳化物由2种形式组成,即絮状碳化物和板条状碳化物。絮状碳化物中富含Hf元素,而Cr元素被富集在板条状碳化物。Confocal laser scanning microscope(CLSM) was used to study the solidification behavior of a nickel-based single crystal superalloy CMSX-4 in real time. SEM and EDS were used to investigate the micromorphology and element segregation characteristics of the solidified samples. Shrinkage and carbide formation were observed during alloy solidification. Results show that three types of shrinkage are found, including square, pentagonal star and angular shrinkages. The formation mechanism of the three types of shrinkage is discussed, which is related to the shape of the enclosed area surrounded by secondary dendrite arms growing in different directions. In addition, carbides are comprised of two forms, namely, flocculent and lath carbide. Hf elements are enriched in flocculent carbides, while Cr elements are enriched in lath carbides.

关 键 词：原位观察 CMSX-4 缩松 碳化物 凝固机理 

分 类 号：TG132.3[一般工业技术—材料科学与工程]