Effect of solidification rate on MC-type carbide morphology in single crystal Ni-base superalloy AM3

• Published in: Transactions of Nonferrous Metals Society of China Vol. 20; no. 10; pp. 1835 - 1840
• Main Author: 余竹焕 刘林 赵新宝 张卫国 张军 傅恒志
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2010; State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,China; Material Science and Engineering Department,Xi'an University of Science and Technology,Xi'an 710054,China%State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,China
• Subjects: carbide morphology; MC型; Ni-base superalloy; single crystal; withdrawing rate; 凝固速度; 单晶镍基高温合金; 单晶高温合金; 扫描电子显微镜; 抽拉速率; 碳化物形态; 碳化物形貌; withdrawing rate; carbide morphology; Ni-base superalloy; single crystal
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(09)60382-4

In order to study the effect of the withdrawing rate on carbide morphology,MC-type carbide in single crystal superalloy AM3 was systematically investigated with sample growth rates from 3.5 μm/s to 500 μm/s.The carbide morphologies were investigated by scanning electron microscopy（SEM）,and the electron probe microanalysis（EPMA） was used to characterize the carbide composition.The results indicate that the solidification rate is the important factor governing MC carbide growth morphology,size and distribution,composition and growth mechanism.With the increase of withdrawing rate,nodular,rod-like,Chinese script types of carbide morphology are observed.For the low withdrawing rate,with the increase of withdrawing rate,the carbide size becomes larger.For the case of dendritic interface,the carbide size becomes smaller with refinement of dendrites as withdrawing rate increases.The volume fraction of carbides increases with the withdrawing rate increasing.