Unusual phase transformation and novel hardening mechanisms upon impact loading in a medium entropy alloy with dual heterogeneous structure

doi:10.1016/j.intermet.2022.107747

CORC > 力学研究所 > 中国科学院力学研究所 > 非线性力学国家重点实验室

	Unusual phase transformation and novel hardening mechanisms upon impact loading in a medium entropy alloy with dual heterogeneous structure
	Zhang, Zihan 1,2; Ma, Yan 2; Qin, Shuang 2; Wang, Jian 1,2; Yang, Muxin 2; Jiang, Ping 2; Wu, Xiaolei 1,2; Yuan, Fuping 1,2
刊名	INTERMETALLICS
	2022-12-01
卷号	151 页码:11
关键词	High-entropy alloys Phase transformation Mechanical properties Shear band Age-hardening Microstructure
ISSN号	0966-9795
DOI	10.1016/j.intermet.2022.107747
通讯作者	Yuan, Fuping(fpyuan@lnm.imech.ac.cn)
英文摘要	Dynamic shear properties and corresponding deformation mechanisms of a CrCoNi-based medium entropy alloy (MEA) with both coherent nanoprecipitate and heterogeneous grain structure were investigated utilizing hat -shaped specimens in Hopkinson-bar and microstructure characterization. The present MEA with dual hetero-geneous structure is found to have extraordinary dynamic shear properties, as compared to the other advanced metals and alloys, including the CrCoNi MEA with similar heterogeneous grain structure while with single FCC phase. A formula for considering effects of strain hardening, strain rate and thermal softening was utilized to calculate the critical shear strain for onset of adiabatic shear band for the present MEA, and the experimental results were found to be well predicted by the theoretical estimations. The formations of microscopic shear bands with low-angle grain boundary type, nano-grains, deformation twins, stacking fault network, and Lomer-Cottrell locks were found to be responsible for the multiple strain hardening mechanisms during dynamic shear defor-mation for both unaged and aged samples. An unusual phase transformation (gamma ->sigma) was observed for only aged samples under dynamic shear loading, which was not found under quasi-static conditions before, should have significant contribution on strain hardening due to the precipitation by-passing hardening by the hard sigma nano -particles.
资助项目	NSFC Basic Science Center Program for Multiscale Problems in Nonlinear Mechanics[11988102] ; National Key R&D Program of China[2017YFA0204402] ; National Natural Science Foundation of China[52192591] ; National Natural Science Foundation of China[11790293]
WOS关键词	SHORT-RANGE ORDER ; LATTICE DISTORTION ; SHEAR BANDS ; DEFORMATION ; GRADIENT ; MICROSTRUCTURE ; PLASTICITY ; BEHAVIOR ; STRESS ; NANOPARTICLES
WOS研究方向	Chemistry ; Materials Science ; Metallurgy & Metallurgical Engineering
语种	英语
WOS记录号	WOS:000888054100001
资助机构	NSFC Basic Science Center Program for Multiscale Problems in Nonlinear Mechanics ; National Key R&D Program of China ; National Natural Science Foundation of China
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/91032]
专题	力学研究所_非线性力学国家重点实验室
通讯作者	Yuan, Fuping
作者单位	1.Univ Chinese Acad Sci, Sch Engn Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China 2.Chinese Acad Sci, Inst Mech, State Key Lab Nonlinear Mech, 15 Beisihuan West Rd, Beijing 100190, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Zihan,Ma, Yan,Qin, Shuang,et al. Unusual phase transformation and novel hardening mechanisms upon impact loading in a medium entropy alloy with dual heterogeneous structure[J]. INTERMETALLICS,2022,151:11.
APA	Zhang, Zihan.,Ma, Yan.,Qin, Shuang.,Wang, Jian.,Yang, Muxin.,...&Yuan, Fuping.(2022).Unusual phase transformation and novel hardening mechanisms upon impact loading in a medium entropy alloy with dual heterogeneous structure.INTERMETALLICS,151,11.
MLA	Zhang, Zihan,et al."Unusual phase transformation and novel hardening mechanisms upon impact loading in a medium entropy alloy with dual heterogeneous structure".INTERMETALLICS 151(2022):11.