Comparative study on microstructure evolution, mechanical properties, and wear behavior of TiC and B4C single-reinforced and hybrid-reinforced Al–Mg–Si alloys by vacuum hot-press sintering

Abstract

To explore the variances between single-reinforced and hybrid-reinforced Al–Mg–Si alloys with TiC and B4C, 10 wt.%-(TiC + B4C)/6061Al, 10 wt.%-B4C/6061Al, 10 wt.%-TiC/6061Al and 6061Al were prepared via wet mixing for 8 h followed by vacuum hot-press sintering at 580 °C and 30 MPa for 2 h. Microstructure evolution, mechanical properties, and wear behavior were investigated in this study. The results show that unlike single reinforcement of TiC, single reinforcement of B4C and hybrid reinforcement of TiC and B4C altered the distribution of Si and facilitated the in-situ formation of SiC. Both single reinforcement and hybrid reinforcement resulted in mixed fracture characteristics of ductile fracture and cleavage fracture, while hybrid reinforcement of TiC and B4C demonstrated superior strength and plasticity matching. At equivalent particle mass fractions, single reinforcement of TiC was more conducive to inducing recrystallization during sintering, followed by single reinforcement of B4C, and hybrid reinforcement of TiC and B4C had the least effect. At equivalent particle mass fractions, single reinforcement of B4C had the most significant effect on improving the wear resistance, followed by hybrid reinforcement of TiC and B4C, and single reinforcement of TiC had the least effect. All particle addition methods demonstrated a mixed wear mechanism involving abrasive wear, adhesive wear, and spalling wear. This study provides valuable insights into the development of aluminum matrix composites.