Improvement in formability of semi-solid cast hypoeutectic Al-Si alloys by equal-channel angular pressing

ECAP process was not able to refine Si particles of the conventional cast alloy as fine as those of the semi-solid cast alloy. Submicron Si particles in the semi-solid cast AC4CH slightly coarsened by warm ECAP. Combination of semi-solid casting and ECAP process provided refinement of Si particles, grain refinement of primary phase, and decrease of hardness difference between primary phase and eutectic. Controlling ECAP processing conditions improved strength and/or ductility and enabled flexible design of mechanical properties of semi-solid AC4CH.