Friction-stir welding of a ductile high entropy alloy: microstructural evolution and weld strength

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:711

Article

Zhu, Z. G.^1,2  Sun, Y. F.³  Ng, F. L.¹  Goh, M. H.¹  Liaw, P. K.⁴  Fujii, H.³  Nguyen, Q. B.¹  Xu, Y.²  Shek, C. H.²  Nai, S. M. L.¹  Wei, J.¹ 

[1] Singapore Inst Mfg & Technol, Singapore, Singapore

[2] City Univ Hong Kong, Dept Phys & Mat Sci, Hong Kong, Hong Kong, Peoples R China

[3] Osaka Univ, Joining & Welding Res Inst, Suita, Osaka, Japan

[4] Univ Tennessee, Dept Mat Sci & Engn, Knoxville, TN 37996 USA

关键词: High entropy alloys;    Friction-stir welding;    Microstructural evolution;    Mechanical properties;    Recrystallization;   

DOI  :  10.1016/j.msea.2017.11.058

来源: Elsevier

【 摘 要 】

High entropy alloys (HEAs) are a novel subset of metallic systems with complex compositions usually yielding simple phase formation. To verify their potential engineering applications, a novel Co16Fe28Ni28Cr28 HEA with a low content of expensive Co was developed and its welding characteristics through friction-stir welding (FSW) were investigated. The HEA shows a stable face-centered-cubic (FCC) structure with an excellent ductility of about 70%. The microstructural evolution during FSW was dominated by discontinuous recrystallization through grain bulging and the B/(B) over bar {112} < 110 > shear texture formed in the stir zone (SZ). A white band (WB) containing W-rich and Cr-rich phases was detected in the SZ. The WB exhibited refined grains compared with the normal SZ, which may be associated with the particle-stimulated nucleation (PSN). The present understanding of the microstructural evolution during FSW of HEAs may help tailor the weld properties to pave the way for their engineering applications.

【 授权许可】

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