Multiphysics simulation and process optimisation for A356 semi-solid slurry fabrication using mechanical stirring with integrated internally cooled cylinders

A novel mechanical stirring method integrating homogeneous A356 internally cooled blocks is developed for A356 semi-solid slurry fabrication. A thermal-flow-phase change multiphysics model is established to investigate the effects of stirring rate and cooling block to melt mass ratio on the evolution of multiphysics fields. The optimal parameters (10% cooling block to melt mass ratio, 2000 r/min) yield the most uniform temperature and solid phase fraction distribution, which is confirmed by both metallographic characterisation and quantitative temperature validation.