VAR熔炼TC2钛合金

The TC2 Titanium Alloy Melting for VAR

摘要: 由于Al、Mn元素在钛合金中的饱和蒸汽压远大于基体元素，因此，TC2钛合金在熔炼中主组元的挥发损失较大，尤其是Mn元素，不利于铸锭化学成分均匀性控制。本文基于活度系数计算模型和控制传质系数计算模型，从热力学角度分析了钛合金熔体中Al、Mn元素的挥发趋势，分析了TC2钛合金中各元素的分布特点，结合生产实际，通过合理控制原材料，选择合适的合金添加剂及熔炼参数等，采用真空自耗电弧炉惰性气体保护熔炼出直径为720 mm的TC2钛合金铸锭，结果表明：所熔炼的铸锭径向、轴向化学成分均匀，生产的铸锭经后续加工，所得到的产品均满足标准要求，未出现宏观偏析。

Abstract: Since the saturated vapor pressure of aluminum and manganese in the titanium alloys are much greater than matrix elements, the volatilization loss of main group elements was greater in melting, especially manganese, which is not conducive to the uniformity control of chemical composition of the ingot. Based on the activity coefficient model and the controlled mass transfer coefficient calculation model, this article analyzes the volatile trend of aluminum and manganese in the titanium melt, and the distribution characteristics of the elements in the TC2 titanium alloys. Combing with the actual production, by the reasonable control of raw materials, and selecting the appropriate alloying additives and melting parameters, TC2 titanium alloy with diameter of 720 mm was melted by VAR with inert gas protection. The results showed that: the chemical composi-tion is uniform in the ingot’s radial and axial direction; the products meet the standard require-ments; and macrosegregation does not appear.