Grain boundary energy effect on grain boundary segregation in an equiatomic high-entropy alloy

doi:10.1103/PhysRevMaterials.4.053603

IMR OpenIR

	Grain boundary energy effect on grain boundary segregation in an equiatomic high-entropy alloy
	Li, Linlin 1,2; Kamachali, Reza Darvishi 1,3; Li, Zhiming 1,4; Zhang, Zhefeng 2
通讯作者	Li, Linlin(l.li@mpie.de)
	2020-05-29
发表期刊	PHYSICAL REVIEW MATERIALS
ISSN	2475-9953
卷号	4 期号:5 页码:11
摘要	Grain boundary (GB) segregation has a substantial effect on the microstructure evolution and properties of polycrystalline alloys. The mechanism of nanoscale segregation at the various GBs in multicomponent alloys is of great challenge to reveal and remains elusive so far. To address this issue, we studied the GB segregation in a representative equiatomic FeMnNiCoCr high-entropy alloy (HEA) aged at 450 degrees C. By combining transmission Kikuchi diffraction, atom probe tomography analysis and a density-based thermodynamics modeling, we uncover the nanoscale segregation behavior at a series of well-characterized GBs of different characters. No segregation occurs at coherent twin boundaries; only slight nanoscale segregation of Ni takes place at the low-angle GBs and vicinal Sigma 29b coincidence site lattice GBs. Ni and Mn show cosegregation of high levels at the general high-angle GBs with a strong depletion in Fe, Cr, and Co. Our density-based thermodynamic model reveals that the highly negative energy of mixing Ni and Mn is the main driving force for nanoscale cosegregation to the GBs. This is further assisted by the opposite segregation of Ni and Cr atoms with a positive enthalpy of mixing. It is also found that GBs of higher interfacial energy, possessing lower atomic densities (higher disorder and free volume), show higher segregation levels. By clarifying the origins of GB segregations in the FeMnNiCoCr HEA, the current work provides fundamental ideas on nanoscale segregation at crystal defects in multicomponent alloys.
资助者	Alexander von Humboldt Stiftung ; German Research Foundation (DFG) within the Heisenberg programme
DOI	10.1103/PhysRevMaterials.4.053603
收录类别	SCI
语种	英语
资助项目	Alexander von Humboldt Stiftung ; German Research Foundation (DFG) within the Heisenberg programme[DA 1655/2-1]
WOS研究方向	Materials Science
WOS类目	Materials Science, Multidisciplinary
WOS记录号	WOS:000536405700002
出版者	AMER PHYSICAL SOC
引用统计	被引频次：97[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/321006/138997
专题	中国科学院金属研究所
通讯作者	Li, Linlin
作者单位	1.Max Planck Inst Eisenforsch GmbH, Max Planck Str 1, D-40237 Dusseldorf, Germany 2.Chinese Acad Sci, Inst Met Res, Wenhua Rd 72, Shenyang 110016, Peoples R China 3.BAM Fed Inst Mat Res & Testing, Unter Eichen 87, D-12205 Berlin, Germany 4.Cent South Univ, Sch Mat Sci & Engn, Changsha 410083, Peoples R China
推荐引用方式 GB/T 7714	Li, Linlin,Kamachali, Reza Darvishi,Li, Zhiming,et al. Grain boundary energy effect on grain boundary segregation in an equiatomic high-entropy alloy[J]. PHYSICAL REVIEW MATERIALS,2020,4(5):11.
APA	Li, Linlin,Kamachali, Reza Darvishi,Li, Zhiming,&Zhang, Zhefeng.(2020).Grain boundary energy effect on grain boundary segregation in an equiatomic high-entropy alloy.PHYSICAL REVIEW MATERIALS,4(5),11.
MLA	Li, Linlin,et al."Grain boundary energy effect on grain boundary segregation in an equiatomic high-entropy alloy".PHYSICAL REVIEW MATERIALS 4.5(2020):11.