Influence of arc current on solidification microstructure of Ti-10V-2Fe-3Al under vacuum arc melting

The influence of remelting current on the solidification macrostructure of Ti-10V-2Fe-3Al under vacuum arc remelting was investigated. Based on the Ampere-Maxwell equation, the relationships among the radius of the pool, intensity of magnetic field and electromagnetic (Lorentz) force were established. The results show that the flow is dominated by weaker buoyancy forces at low arc current, in this case, heat dissipation accelerate, the solidification microstructure becomes finer. With increasing arc current, the liquid metal flow is electromagnetically driven by Lorentz force, the heat is taken inside from superstratum of the pool, the temperature gradient in the pool increases, and the solidification microstructure becomes coarser.