镁合金铸件缺陷搅拌摩擦修复工艺方法

Technological Feasibility of Friction Stir Processing for Magnesium Alloy Casting Defects Repair

针对航天器铸件缺陷率高,修复难度大的现状,提出采用搅拌摩擦加工技术实现缺陷修复的新方法。首先制备了含缺陷的AZ91D镁合金试板,并以此作为实验材料进行了搅拌摩擦修复工艺实验,在旋转速度为500r/min,前进速度100mm/min,下压量为1.5mm的工艺参数下,修复区域成形良好。修复前后X射线照片表明,搅拌摩擦加工技术有效修复了镁合金试板中的铸造缺陷。最后对航天器铸件中常见的T形结构和角形结构开展了对应的实验研究,在现有条件下,采用自制简易夹具,可以完成T形结构和角形结构的搅拌摩擦加工。研究结果表明,采用搅拌摩擦方法修复航天器铸件缺陷从技术上是可行的。

A friction stir processing（FSP） technology used to repair casting defects in magnesium alloys on spacecraft is proposed,aimed at the high defect rate and repair difficulty.AZ91D magnesium alloy sample plate with defects was prepared as the experimental material to be repaired in the FSP experiments.It was found that with the proper parameters of FSP（rotation speed 500r/min,traveling speed 100mm/min,plunge depth 1.5mm）,the repaired region had very good aspect.By comparing the X-ray photos of sample plates before FSP repairing and after that,it could be concluded that the FSP technology can repair casting defect of magnesium alloy in sample plates.Feasibility experiments for application of FSP in T-shaped structure and the angular structure were also conducted,which are common structures in aerospace products.With simple fixture the T-shaped structure and angular structure was simulated and FSP experiment was successfully finished.The results show that the method of repair casting defect in magnesium alloys using FSP method is technically feasible.