Effect of severe cold-rolling and annealing on microstructure and mechanical properties of AlCoCrFeNi2.1 eutectic high entropy alloy

7th International Conference on Nanomaterials by Severe Plastic Deformation

Wani, I.S.^1 ; Bhattacharjee, T.^2,5 ; Sheikh, S.^3 ; Lu, Y.^4 ; Chatterjee, S.^1 ; Guo, S.^3 ; Bhattacharjee, P.P.^1 ; Tsuji, N.^2,5

Department of Materials Science and Metallurgical Engineering, IIT Hyderabad, India^1

Department of Materials Science and Engineering, Kyoto University, Japan^2

Materials and Manufacturing Technology, Chalmers University of Technology, Gothenburg

SE-41296, Sweden^3

Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian

116024, China^4

Elements Strategy Initiative for Structural Materials (ESISM), Kyoto University, Japan^5

关键词: Duplex microstructures;    High entropy alloys;    Microstructural refinement;    Microstructure and mechanical properties;    Nano-crystalline structures;    Ordered structures;    Severe cold rolling;    Strength ductility balance;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/194/1/012018/pdf
DOI  :  10.1088/1757-899X/194/1/012018

来源: IOP

【 摘 要 】

The possibility of microstructural refinement and improvement of mechanical properties by severe cold-rolling was investigated in an AlCoCrFeNi2.1lamellar eutectic high entropy alloy (EHEA). The as-cast alloy revealed fine scale eutectic mixture of L12(ordered FCC) and B2 (ordered BCC) phases. During severe cold-rolling up to 90% reduction in thickness the B2 phase maintained the ordered structure, while the L12phase showed the evolution of a nanocrystalline structure and progressive disordering. Annealing of the severely cold-rolled material resulted in the formation of duplex microstructures composed of two different phases with equiaxed morphologies and significant resistance to grain growth up to 1200°C. Annealing at 1000°C resulted in an optimum strength-ductility balance with the tensile strength of 1175 MPa and the total elongation of 23%. The present results showed that severe cold-rolling and annealing can impart very attractive mechanical properties in complex EHEAs.