Behavior of A356 Alloy in Semi-Solid State Produced by Mechanical Stirring

Abstract

This investigation studied semi-solid (SSM) aluminum-silicon alloy produced by mechanical stirring. Aluminum alloys produced by this method, are widely used instead of conventional die casting and forging processes. In this research by using a mechanical stirrer slurry maker, the effects of stirring speed, the solid fraction percent and mold temperature are investigated on micro-structure and hardness of A356 aluminum alloy in semi-solid casting. By optimizing the forming parameters, dendrite microstructure changes to globular and mechanical properties improves. This is because of breaking and globularizing dendrites of primary α-AL phase. It is determined that stirring temperature of 608°C and stirring speed of 300 RPM leads to the uniform grains distribution and therefore arrives to better hardness for the produced billets.