The eutectic characteristic of MC-type carbide precipitation in a DS nickel-base superalloy

IMR OpenIR

	The eutectic characteristic of MC-type carbide precipitation in a DS nickel-base superalloy
	W. R. Sun; J. H. Lee; S. M. Seo; S. J. Choe; Z. Q. Hu
	1999
发表期刊	Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing
ISSN	0921-5093
卷号	271 期号:1-2 页码:143-149
摘要	The precipitation of MC-type carbide in a DS nickel-base superalloy has been studied. The nucleating temperature of the MC carbide was determined by analysis. The MC carbide and gamma phase were complementary in composition, and the eutectic reaction of (gamma + MC) took place in different forms at varied solidification rate. The (gamma + MC) eutectic reaction was an important factor of determining the carbide morphology. At an extremely high solidification rate, such as quenching, the compositional ranges for the (gamma + MC) eutectic reaction was broadened and the carbide precipitated through the quasi-eutectic reaction of (gamma + MG). As a result, the carbide appearing frequency was increased noticeably The dendrites of the quasi-eutectic carbide formed in quenching paralleled to each other closely for facilitating diffusion between the two eutectic components of carbide and gamma phase. The script carbide precipitated at a relatively high drawing rate around 50 mu m/s. At this rate, diffusion was insufficient and the eutectic reaction of (gamma + MC) was suppressed at most. The carbide grew quickly along the interdendritic liquid passages due to the high degree of segregation of carbide forming elements there, and hence formed a very complicated dendritic structure. The faceted carbides precipitated when the drawing rate was lower than 5 mu m/s, and some of them contained a gamma phase core. The incorporation of gamma phase into the carbide body was caused by the eutectic reaction of (gamma + MC) in the midst of the carbide precipitation. Two forms of the (gamma + MC) eutectic reaction were favored by sufficient diffusion at 0.5 mu m/s drawing rate. The (gamma + MC) eutectic reaction took place at the final stage of the carbide precipitation in an isolated liquid pool and formed small ridges distributed uniformly on the carbide surface. Diffusion operated sufficiently throughout the whole residual liquid passage guaranteed the continual eutectic reaction by a sandwich like mode of gamma/MC/gamma, and the extremely long carbide was formed along the grain boundaries as a result. (C) 1999 Elsevier Science S.A. All rights reserved.
部门归属	chinese acad sci, inst met res, dept superalloys & special castings, shenyang 110015, peoples r china. changwon natl univ, dept met & mat sci, changwon 641773, kyungnam, south korea. korea inst machinery & mat, high temp mat lab, changwon 641010, kyungnam, south korea. chinese acad sci, inst met res, state key lab rapidly solidified nonequilibrium a, shenyang 110015, peoples r china.;sun, wr (reprint author), chinese acad sci, inst met res, dept superalloys & special castings, 72 wenhua rd, shenyang 110015, peoples r china
关键词	Carbide Precipitation Superalloy Directional Solidification
URL	查看原文
WOS记录号	WOS:000083647800020
引用统计	被引频次：62[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/37495
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	W. R. Sun,J. H. Lee,S. M. Seo,et al. The eutectic characteristic of MC-type carbide precipitation in a DS nickel-base superalloy[J]. Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing,1999,271(1-2):143-149.
APA	W. R. Sun,J. H. Lee,S. M. Seo,S. J. Choe,&Z. Q. Hu.(1999).The eutectic characteristic of MC-type carbide precipitation in a DS nickel-base superalloy.Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing,271(1-2),143-149.
MLA	W. R. Sun,et al."The eutectic characteristic of MC-type carbide precipitation in a DS nickel-base superalloy".Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing 271.1-2(1999):143-149.