Advances in Directional Solidification Techniques of Superalloys

This paper first reviews the history of the development of directional solidification,focusing on analysis of liquid metal cooled directional solidification characteristics.We summarize solidification microstructure and mechanical properties of selected directionally solidified and single crystal superalloy prepared under high thermal directional solidification with author's research features in this field.The effects of thermal gradient,solidification rate,crystal orientation,melt-superheating and melt convection on the microstructure and mechanical properties of superalloys were analyzed.We conclude that the high thermal gradient directional solidification is an important way to refine the microstructure,reduce defects,and improve performance of superalloys.Finally,the future trends directional solidification of superalloys was prospected.