镁合金在HFC-32气氛中熔炼的研究

Research on Magnesium Melting Protected by Cover Gas Mixtures Containing HFC-32

研究了HFC-32气氛对镁及镁合金在熔炼过程中的保护效果,并对其保护机理进行了探讨。结果表明:含0.1%体积浓度的HFC-32保护气体可以较好地起到保护作用;气体浓度越高,温度越低,保护效果越好;试样的扫描电镜、X射线衍射分析显示氧化膜很致密,它由氧化镁、氟化镁等组成,起到了保护作用。氧化增重实验显示镁合金在HFC-32气氛中氧化曲线遵循抛物线规律。

The protective effects of HEC-32 mixed gases in melting process of magnesium and magnesium alloys were experimentally studied and the protective mechanism was analyzed. The results show that the protective atmosphere of air containing 0.1% HFC-32 has a fairly good protective effect. The higher the HFC-32 concentration and the lower the temperature, the better the protection effect. The SEM and XRD results showed that the surface films are composed of MgO and MgF2 phases and are compact enough to protect the magnesium melt. Oxide films on thermogravimetric measurements of weight change were proved to be growing with the parabolic law.