Refining and reinforcing effects of TiC-Al₂O₃/Al ribbons inoculant on Al–Si–Mg–Ti alloy

Abstract

In this study, TiC-Al2O3/Al ribbons inoculant were prepared by mechanical alloying, spark plasma sintering (SPS) and melt spinning. Adding 5vol.% TiC-Al2O3/Al ribbons to an Al-Si-Mg-Ti (ASMT) alloy melt significantly refined the α-Al grains from 28.5 μm to 14.9 μm. In addition, the morphology of the eutectic silicon were modified and optimized, changing from needle-like silicon to spherical silicon. Adding the TiC-Al2O3/Al ribbons significantly improved the mechanical properties of TiC-Al2O3/Al-Si-Mg-Ti (TAASMT) alloy, including its elastic modulus (EM), yield strength (YS), ultimate tensile strength (UTS) hardness, and elongation which were increased by 5.4%, 18.4%, 32.7%, 8.3%, and 62.3%, respectively. These increases in the mechanical properties could be attributed to the intracrystalline reinforcement of the Al2O3 and TiC nanoparticles, well-bonded particle/matrix interface, modification of the eutectic silicon phases, and synergistic effects of the Orowan strengthening, Coefficient of thermal expansion (CTE) mismatch strengthening, load transfer, grain refining strengthening, and geometrically necessary dislocations (GND) strengthening.

Optimizing the Parameters of Spark Plasma Sintering to Enhance the Hardness of MgO/TiC Composites

“…Using XRD characterization, the impact of TiC on the crystalline structure of the pure MgO matrix was analyzed. To form MgO-TiC composites, the wettability between the MgO and TiC matrix reinforcement must be high [34]. Due to the interaction between the TiC reinforcement and the MgO's crystalline structure, the MgO's base texture was altered.…”