镁合金熔液除气工艺优化及其机理的研究  

Optimization of Degassing Process for Magnesium Alloy Melt and Its Mechanism

作　　者：许四祥[1] 吴树森[2] 高培青[1] 

机构地区：[1]安徽工业大学机械工程学院,安徽马鞍山243002 [2]华中科技大学材料成形及模具技术国家重点实验室,湖北武汉430074

出　　处：《铸造》2008年第8期826-829,共4页Foundry

基　　金：国家自然科学基金(50775086)

摘　　要：利用镁合金快速定量测氢仪研究了通Ar对AZ91镁合金熔体除气的效果,以及通Ar流量、通Ar时间及精炼温度三因子对精炼效果的影响。运用正交试验方法找到了通Ar除气工艺的最佳工艺参数匹配,即通Ar流量为1-1.5 L/min,通Ar时间为20-25 min,镁液温度为725-750℃。从热力学角度对镁液的除气机理进行了深入探讨,建立了导入镁熔体中惰性气体体积的定量热力学关系式。并进行了动力学方面的分析,通过试验发现,在理想条件下所推导的除气速率动力学方程式只能作为实际工程参考,理论计算与实际数值由于多个因素的影响无法较好吻合。Through blowing Ar into Mg melt and stirring, and by means of a rapid hydrogen-content measuring instrument, the influences of three factors, Ar flux, degassing time and temperature, on degassing efficiency of AZ91 melt were studied. The optimal parameters, Ar flow rate of 1-1.5 L/min, degassing time of 20-25 rain and magnesium melt temperature of 725-750 ℃, were obtained by using of orthogonal test. The degassing mechanism of magnesium alloy melt was analyzed according to thermodynamic theory, and the thermodynamic equations of Ar gas volume entered into the melt had been established. Furthermore, degassing dynamics was also analyzed and the experimental result showed that the theoretical data was not in agreement with the real values owing to several factors＇influence, and the deduced dynamic equation of degassing rate could be only used for reference in practice.

关 键 词：镁合金熔液 除氢 正交设计 热力学 动力学 

分 类 号：TG146.22[一般工业技术—材料科学与工程]