Evolution of the mechanical properties of a cobalt-based alloy under thermal shocks

doi:10.1016/j.matdes.2019.108425

	Evolution of the mechanical properties of a cobalt-based alloy under thermal shocks
	Wen, Junxia 1,3,4; Che, Hongyan 2; Cao, Rui 4; Dong, Hao 2; Ye, Youxiong 3; Zhang, Haiyan 4; Brechtl, Jamieson 5; Gao, Yanfei 3; Liaw, Peter K.3
	2020-03-01
关键词	Carbides Electronics packaging Hot isostatic pressing Mechanical properties Microstructural evolution Nanoindentation Scanning electron microscopy Sintering Thermal fatigue Thermal shockCarbide particles Cobalt base alloys Cobalt based alloy Energy dispersion spectrum High stress concentration Nanoindentation tests Reduced modulus Thermal fatigue cracks
卷号	188
DOI	10.1016/j.matdes.2019.108425
英文摘要	A cobalt-base alloy manufactured by hot isostatic pressing sintering (HIP) was investigated in the present work. A series of quenching thermal-shock experiments were carried out to study the effects of thermal-cycle shocks on this new cobalt-based alloy. Scanning Electron Microscope (SEM) and Energy Dispersion Spectrum (EDS) were employed to observe the evolution of microstructures under thermal-shock cycles. Results show that some floccus Co3W3C precipitated around the WC particles after several thermal-shock cycles. These precipitates and the carbide particles correspond to the locations with the high-stress concentration. The mechanical properties evolution under thermal-shock cycles was analyzed by Nanoindentation tests. The nanohardness presents no noticeable change with thermal-shock cycles. However, the reduced modulus demonstrates a decreasing trend with the thermal-shock cycles. The variation of the mechanical properties has an unestimated relationship with the residual stress and densities of dislocations caused by thermal shocks. Furthermore, the present work pointed out that the precipitates around the carbides are the places where the thermal fatigue crack initiated. How to deal with the precipitates will be the optimized way for this material. © 2018
会议录	Materials and Design
会议录出版者	Elsevier Ltd
语种	英语
ISSN号	02641275
WOS研究方向	Materials Science
WOS记录号	WOS:000514567900023
内容类型	会议论文
源URL	[http://ir.lut.edu.cn/handle/2XXMBERH/132668]
专题	材料科学与工程学院
作者单位	1.School of Mechanical and Electrical Engineering, Liuzhou Vocational &Technical College, Liuzhou; 545006, China; 2.Advanced Technology & Materials Limited Company, China Iron & Steel Research Institute Group, Beijing; 100081, China; 3.Department of Materials Science and Engineering, The University of Tennessee, Knoxville; TN; 37996, United States; 4.State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal, Lanzhou University of Technology, Lanzhou; 730050, China; 5.The Bredesen Center for Interdisciplinary Research and Education, The University of Tennessee, Knoxville; TN; 37996, United States
推荐引用方式 GB/T 7714	Wen, Junxia,Che, Hongyan,Cao, Rui,et al. Evolution of the mechanical properties of a cobalt-based alloy under thermal shocks[C]. 见:.