The evolution of carbides during long-term creep/aging of nickel based superalloy K444

doi:10.1016/j.jmrt.2023.12.236

IMR OpenIR

	The evolution of carbides during long-term creep/aging of nickel based superalloy K444
	Cai, Hang 1,2; Hou, Jieshan 1; Guo, Yong-an 1; Xing, Jing 1,2; Zhou, Lan-zhang 1
通讯作者	Hou, Jieshan(jshou@imr.ac.cn) ; Zhou, Lan-zhang(lzz@imr.ac.cn)
	2024
发表期刊	JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
ISSN	2238-7854
卷号	28 页码:3631-3640
摘要	In K444 alloy, the evolution of carbides during stress aging (creep) and stress-free aging at 900 degrees C for 5000 h, and interrupted at 3000 h were investigated, combining microstructure characterization and quantitative statistics method. After stress-free aging for 5000 h, the volume fraction of intragranular MC and M6C carbides decrease from 0.48 % to 0.66 %-0.26 % and 0.48 %, respectively, while that of M23C6 carbides increase to 0.28 %. The two degradation behaviors can be concluded as MC + gamma -> M6C + M23C6 + gamma ' and M6C + gamma -> M23C6 + gamma ' respectively. The former controlled by the diffusion of Ti occurred earlier, while the latter determined by the diffusion of W and Mo mainly happened later. The applied stress did not change degradation reactions while accelerate the degradation rate slightly. During stress-free aging, the morphology of grain boundaries (GBs) changed from discrete distribution to semi-continuous and then to continuous chain, and the content of MC and M6C carbides decreases while that of M23C6 carbides increases. The applied stress markedly promotes above behaviors. Especially, the completed continuous chain formed before 3000 h. Moreover, the applied stress induced the formation of cavitation on the GBs, which is attributed to the following reasons. First, it can accelerate the degradation of GBs and decline the GBs strength. What's more, dislocations pile up on the GBs and cause a high level of stress concentration. Finally, the new generated phase interfaces have a greater deviation with its adjacent carbides, weakening the binding force of GBs.
关键词	Ni -based superalloy Long -term aging Carbides degradation Grain boundaries Applied stress
资助者	National Science and Technology Major Project ; National Natural Science Foundation of China (NSFC)
DOI	10.1016/j.jmrt.2023.12.236
收录类别	SCI
语种	英语
资助项目	National Science and Technology Major Project[Y2019-VII-001 1-0151] ; National Natural Science Foundation of China (NSFC)[51571191]
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
WOS记录号	WOS:001155154300001
出版者	ELSEVIER
引用统计
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/183967
专题	中国科学院金属研究所
通讯作者	Hou, Jieshan; Zhou, Lan-zhang
作者单位	1.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, Hefei 230026, Peoples R China
推荐引用方式 GB/T 7714	Cai, Hang,Hou, Jieshan,Guo, Yong-an,et al. The evolution of carbides during long-term creep/aging of nickel based superalloy K444[J]. JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T,2024,28:3631-3640.
APA	Cai, Hang,Hou, Jieshan,Guo, Yong-an,Xing, Jing,&Zhou, Lan-zhang.(2024).The evolution of carbides during long-term creep/aging of nickel based superalloy K444.JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T,28,3631-3640.
MLA	Cai, Hang,et al."The evolution of carbides during long-term creep/aging of nickel based superalloy K444".JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T 28(2024):3631-3640.