Effect of Hot-Plate Rolling on the Microstructure Evolution and Mechanical Properties of In-Situ Nano-TiCP/Al-Mg-Si Composites

The hot-plate rolling (HPR) process is adopted to achieve the optimal strength-ductility for the in-situ nano-TiC/Al-Mg-Si composites.There was no crack in the sheet by single pass of hot-plate rolling with a thickness reduction of 80%,while there were numerous cracks in the sheet by two passes of conventional hot rolling to achieve a total reduction of 50%.The microstructure and mechanical properties of the composites subjected to 80% thickness reduction of hot rolling at 540 ℃ were investigated by tensile tests,scanning electron microscopy,and electron backscatter diffraction.The yield strength and ultimate tensile strength of in-situ nano-TiC/Al-Mg-Si composites after the hot-plate rolling process and T6 heat treatment increased significantly due to the dislocation strengthening and precipitation strengthening.