Numerical simulation of macrosegregation heredity on TC4 titanium alloy ingot by vacuum arc remelting

Abstract

In this study, Fluent software is used to simulate the interaction between temperature and solute fields during the process of vacuum arc remelting. The heredity law of macrosegregation of the easily segregated Fe element between the primary and secondary ingots is examined. The results shows that macrosegregation of the primary ingot has a genetic effect on the macrosegregation of secondary ingots. Compared with the primary ingot, the negative segregation in the surface area of the secondary ingot leads to a certain increase. When the position and direction of the lower part of the primary ingot are unchanged, the negative segregation in the surface area of the secondary ingot exhibits the highest increase, and the negative segregation degree increases by 0.42. When the position and direction of the upper part of the primary ingot remains unchanged, the positive segregation in the core of the secondary ingot exhibits the highest increase, and the positive segregation degree increass by 0.57. When the upper and lower parts of the primary ingot are exchanged and the upper half is downward, the positive segregation degree of the secondary ingot core is reduced by 0.17. When upper and lower parts of the primary ingot switch positions and directions of the upper and lower parts are downward, the center segregation of the secondary ingot is improved when compared to that of the primary ingot, and processing of the primary ingot is not required. This is turn leads to greater significance in actual production.