采用数值模拟方法分析影响VAR熔炼钛合金铸锭表面质量的因素

Computational simulation of the influences on ingot

摘要:

随着钛合金产业的发展,对于钛合金产品成本的控制成为重要竞争力。钛合金铸锭的成品率与铸锭的表面质量密切相关。本文采用数值模拟方法分析影响铸锭表面质量的因素,借此达到提高铸锭成品率的目的。通过MeltFlow软件对VAR熔炼过程的温度场进行分析,将高温液相与坩埚接触长度与表面质量建立联系。分析得出,从工艺角度考虑,熔炼电流、稳弧电流以及稳弧周期这三个因素对铸锭表面质量有影响,结合实验验证表明,采用较大的熔炼电流、大稳弧电流以及短稳弧周期有利于铸锭表面质量提高,提高成品率。

关键词:VAR;数值模拟;钛合金;表面质量

Abstract:

With the development of titanium alloy industry, the cost control of titanium alloys" products has become an important competitiveness. The yield rate of titanium alloy ingots is closely related to the surface quality of ingot. In this paper, the factors affecting the surface quality of ingots are analyzed by numerical simulation to improve the yield rate. We used meltflow VAR software to analyze the temperature field in VAR process, the relationship between the surface quality and the contact length, which represent the distance between the high temperature liquid phase and crucible wall are established. It is concluded that the three factors, melting current, stirring coils current and period have influnces with the surface quality of ingots. the experiment results show that the higher melting current, the greater stirring coils current and the shorter coils current period are beneficial to improve the surface quality and yield rate of ingots.

Key words:Vacuum arc remelting; Numerical simulation; titanium alloys; surface quality of ingots