Abstract：The large specification flat ingots of Ti6242 titanium alloy were prepared by using 3150KW electron beam cold hearth melting (EB) furnace. The mathematical model of saturated vapor pressure and volatilization law of various elements in EB melting process of Ti6242 titanium alloy was established by using Langmuir law. The relationship between the smelting process parameters and the homogeneity of the chemical composition of ingot was analyzed. The results showed that Al and Sn elements of Ti6242 titanium alloy volatilized seriously in EB furnace melting, and the actual volatilization rate was 12.27% and 7.86% respectively, which was in good agreement with the volatilization model (theoretical volatilization rate was 11.68% and 9.825% respectively). The optimum melting speed of the 3150KW electron beam cooling hearth melting (EB) furnace is 1.28×10-4 m/s (700 Kg/h). Under this process condition, the chemical composition of the ingot has good uniformity and fully meets the requirements of GB/T 3620.1-2007. The macrostructure of Ti6242 titanium alloy was equiaxed grain structure, which is obviously different from VAR ingot. The flat ingot of Ti6242 titanium alloy prepared by EB furnace single smelting can be used for direct rolling to sheet, and the round ingot can be used to prepare high quality and large size bar, realizing the low cost and short process of titanium alloy preparation.
2020, Vol. 27 