Toward Enhanced Strength and Ductility of Al-14.5Si Alloy via Solidification Under Super-Gravity Field

Herein, a novel method to improve the mechanical properties of Al-14.5Si alloys via solidification under super-gravity field is reported. The Al-14.5Si alloys are solidified under normal gravity (1 g) and various super-gravity fields (1000 g, 2000 g, 3000 g, and 4000 g), respectively. The results indicate that the solidification under super-gravity field leads to right shifting of eutectic point and significant refinement of the eutectic Si. The refining of eutectic Si has a tremendous influence on mechanical properties. The elongation and fracture toughness of the Al-14.5Si alloys, solidified under super-gravity field of 3000 g, can reach up to approximate to 12.7% and approximate to 20.21 MPam, which are approximately tenfold and three times higher relative to those under normal gravity, respectively. The fracture mode of Al-14.5Si alloy is transformed from brittle fracture under normal gravity to ductile fracture under super-gravity field.