Thermal Stability of Microstructure and Mechanical Properties of High Pressure Solidified Al2O3/Al-10Si

Al2O3/Al-10Si composites were prepared by high pressure solidification at 3, 4, 5 GPa, and then heat treated at 160℃ for 2, 4, and 6 h. Thermal stability of microstructure and mechanical properties of the Al2O3/Al-10Si composites under high pressure were studied. The results indicate that heat treatment leads to the precipitation of Si particles due to the supersaturation in α phase. The precipitation of Si causes a decrease in supersaturation. The compression strength and ration show a slight increase after heat treatment due to the combination of precipitation strengthening and solid solution strengthening. At 160℃/4 h, Al2O3/Al-10Si composites exhibit the best mechanical properties. After solidified under 5 GPa and heat treatment at 160℃/4 h, Al2O3/Al-10Si composites get the maximum compressive strength which is about 716 MPa. © 2020, Science Press. All right reserved.