Preparation and properties of AlFeNiCrCoTi0.5 high entropy alloy particle reinforced 6061 aluminum matrix composites

Abstract

AlFeNiCrCoTi0.5 high entropy alloy powder was prepared by mechanical alloying, and (AlFeNiCrCoTi0.5)p/6061Al composites were prepared by cold isostatic pressing combined with equal-channel angular pressing. The alloying behavior between elemental metals and effects of milling time on powder morphology of high entropy alloy were investigated. The microstructure and properties of (AlFeNiCrCoTi0.5)p/6061Al composites with different volume fractions were analyzed. The results show that the alloying time of AlFeNiCrCoTi0.5 metal powder increases with the increase of melting point of the elements. The higher the melting point of the elements, the earlier the alloying. AlFeNiCrCoTi0.5 metal powder is fully alloyed and forms a FCC+BCC two-phase solid solution structure after 70 h ball milling time. A transition layer of element infiltration of elements is formed between Al matrix and the reinforcement. With the increase of the volume fraction of reinforcement, the agglomeration of reinforcement is intensified, the tensile strength increases and the plasticity decreases. When the volume fraction is 10%, the composites have good comprehensive properties. Compared with 6061 aluminum matrix, the tensile strength increases by 21.8% and the elongation decreases by 7.4%. For the composites after T6 treatment, the tensile strength and the elongation are 284.05 MPa and 11.51%, respectively.

Keywords

• high entropy alloy
• aluminum matrix composites
• microstructure
• mechanical property