Effects of rheo-squeeze casting parameters on microstructure and mechanical properties of AlCuMnTi alloy

The semisolid slurry of AlCu5MnTi alloy was prepared by indirect ultrasonic vibration (IUV), in which the horn was vibrated under the outside of the metallic cup containing alloy melt, then the slurry was formed by direct squeeze casting (SC). The effects of applied pressure, mould temperature and heat treatment on microstructure and mechanical properties of rheo-squeeze casting (RSC) AlCu5MnTi alloy were studied. The results show that with the increase of pressure, the average diameter of grain decreased continuously, while the average shape factor increased. With the increase of mould temperature, mechanical properties of RSC samples increased firstly and decreased afterward. When the pressure was 100 MPa and the mould temperature was 270 °C samples achieved the best mechanical properties after T5 heat treatment. The tensile strength and elongation were 326.5 MPa and 11% respectively, which were improved by 6.5% and 47% respectively compared with conventional squeeze casting samples.