Effect of Technological Parameters on Macrostructure of Titanium Alloys by Directional Solidification Using Cold Crucible

Abstract:

Electromagnetic cold crucible directional solidification technology combines the advantages of electromagnetic cold crucible technology and directional solidification technology, and can provide a new effective way for directional solidification of refractory and active metals. But the process is complicated and has many influencing factors. The effects of technological parameters on the macrostructure are studied by orthogonal experiment in order to know about the process of cold crucible directional solidification and the evolution rule of macrostructure. The results show that the withdrawal velocity is the most important one in all factors affecting the macrostructure. The grain numbers are decreased with decreasing the withdrawal velocity, and the directional solidified macrostructure can be obtained with a velocity of 1 mm/min. Theoretical analysis shows that the effects of technological parameters on macrostructure are by changing the shape and position of the solidificational interface and front, and the heats of absorption and loss.

Key words:titanium alloys; cold crucible; directional solidification; macrostructure