Development of Al-15%Si Hypereutectic Alloy Automotive Part by Local Squeeze and Vacuum Diecasting

A functional automotive part, reaction shaft support, was fabricated by local squeeze and vacuum Diecasting (LSVD) with light-weight Al-15%Si hypereutectic alloy which has good fluidity and excellent wear resistance. The effects of local squeezing pressure and time-lag of LSVD process on the microstructure of the product were investigated. Measurement of specific gravity with the change of local squeeze pressure and time-lag showed that the local squeezing effect can be increased by increasing squeeze pressure and decreasing time-lag. However, too high a squeeze pressure and too a low time-lag brought about insufficient squeezing effect due to instant movement to the squeeze plunger stroke end point. Through the combination of vacuum suction before melt injection and local squeezing after melt injection in LSVD process, light-weight Al-15%Si alloy reaction shaft support was successfully developed, resulting in excellent microstructural and mechanical properties