Parallel preparation of multi-component alloys with composition gradient distribution and their nonlinear microstructures and mechanical properties

Abstract

Designing the precise composition with high performance remains a challenge for multi-component alloys (MCAs). In this work, we carry out a new high-throughput synthesis method for Zr-Al-Ti-V-Cr MCAs, and amounts of independent specimens with gradient compositions are prepared in parallel at one time. Their microstructures and mechanical properties are investigated. It’s found that the specimen’s structure transforms from fully amorphous to composite structures with amorphous and bcc-structured nanocrystals with increasing Zr content. The specimen with a composition of Zr84Al4Ti4V3Cr5 is screened out to possess the highest nanohardness of ~ 5.91 GPa and elastic modulus of ~ 120.33 GPa, which is attributed to its amorphous structure wrapped with tiny nanocrystals. Interestingly, it shows nonlinear relationships between the chemical composition, microstructures, and mechanical properties, and the specimens with low mixed entropy present high nanohardness and elastic modulus compared to those with high mixed entropy. This work provides a clue for the parallel development of MCAs with excellent performance.