Effect of Co on Microstructure and Stress Rupture Properties of K4750 Alloy

doi:10.1007/s40195-019-00936-w

IMR OpenIR

	Effect of Co on Microstructure and Stress Rupture Properties of K4750 Alloy
	Li, Xiao-Xiao 1,2; Ou, Mei-Qiong 1; Wang, Min 1; Hao, Xian-Chao 1; Ma, Ying-Che 1; Liu, Kui 1
通讯作者	Ou, Mei-Qiong(mqou@imr.ac.cn) ; Ma, Ying-Che(ycma@imr.ac.cn)
	2019-12-01
发表期刊	ACTA METALLURGICA SINICA-ENGLISH LETTERS
ISSN	1006-7191
卷号	32 期号:12 页码:1501-1510
摘要	The effects of substituting Co for Fe on the microstructure and stress rupture properties of K4750 alloy were studied. The microstructure of the alloy without Co (K4750 alloy) and the alloy containing Co (K4750-Co alloy) were analyzed. Substitution of Co for Fe inhibited the decomposition of MC carbide and the precipitation of eta phase during long-term aging treatment. In K4750-Co alloy, the morphology of MC carbide at the grain boundary (GB) remained dispersed blocky shape and no eta phase was observed after aging at 750 degrees C for 3000 h. However, in K4750 alloy, almost all the MC carbides at GBs broke down into granular M23C6 carbide and needle-like eta phase. The addition of cobalt could delay the decomposition of MC carbides, which accordingly restricted the elemental supply for the formation of eta phase. The stress rupture tests were conducted on two alloys at 750 degrees C/430 MPa. When Co is substituted for Fe in K4750 alloy, the stress rupture life increased from 164.10 to 264.67 h after standard heat treatment. This was mainly attributed to increased concentration of Al, Ti and Nb in gamma ' phase in K4750-Co alloy, which further enhanced the strengthening effect of gamma ' phase. After aging at 750 degrees C for 3000 h, substitution of Co for Fe can also cause the stress rupture life at 750 degrees C/430 MPa to increase from 48.72 to 208.18 h. The reason was mainly because MC carbide degradation and eta phase precipitation in K4750 alloy, which promoted the initiation and propagation of micro-crack during stress rupture testing.
关键词	Nickel-based superalloy Co addition MC degradation Stress rupture property
DOI	10.1007/s40195-019-00936-w
收录类别	SCI
语种	英语
WOS研究方向	Metallurgy & Metallurgical Engineering
WOS类目	Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000495116000007
出版者	CHINESE ACAD SCIENCES, INST METAL RESEARCH
引用统计	被引频次：4[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/321006/137026
专题	中国科学院金属研究所
通讯作者	Ou, Mei-Qiong; Ma, Ying-Che
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Liaoning, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, Hefei 230026, Anhui, Peoples R China
推荐引用方式 GB/T 7714	Li, Xiao-Xiao,Ou, Mei-Qiong,Wang, Min,et al. Effect of Co on Microstructure and Stress Rupture Properties of K4750 Alloy[J]. ACTA METALLURGICA SINICA-ENGLISH LETTERS,2019,32(12):1501-1510.
APA	Li, Xiao-Xiao,Ou, Mei-Qiong,Wang, Min,Hao, Xian-Chao,Ma, Ying-Che,&Liu, Kui.(2019).Effect of Co on Microstructure and Stress Rupture Properties of K4750 Alloy.ACTA METALLURGICA SINICA-ENGLISH LETTERS,32(12),1501-1510.
MLA	Li, Xiao-Xiao,et al."Effect of Co on Microstructure and Stress Rupture Properties of K4750 Alloy".ACTA METALLURGICA SINICA-ENGLISH LETTERS 32.12(2019):1501-1510.