Optimization of process parameters on microstructure and mechanical properties of ADC 12 alloy Aptomat Contact fabricated by thixo-extrusion

The mechanical properties of thixoextrusion components can be improved by controllable processing parameters such as the solid fraction of alloy, holding time, punch velocity, heat treatment and die temperature. In this study, the effects of thixoforming parameters on the microstructures and mechanical properties of thixoextrusion ADC12 alloy Aptomat Contact are studied. ADC 12 has excellent castability with high fluidity and low shrinkage rate, so it is widely used in industry, especially in automotive and motorcycle engine part casting. It is a near eutectic alloy with high strength and low ductility (1%). The optimization parameters mechanical properties were investigated by changing the punch velocity, specimen temperature and holding time. The results also indicated optimal value at punch velocity (13mm/s), specimen temperature (570^oC) and holding time (7 minutes) which was changed microstructure from eutectic dendrite to globular grain increasing the ductility (7%) of this alloy during the semi-solid forming process while remaining mechanical properties leads to an increase in the quality of finished parts.