一种先进高强钛合金电子束焊接头组织与性能的研究  

Microstructures and properties of EB welds of an advanced high strength titanium alloy

作　　者：郭绍庆[1] 余槐[1] 张文扬[1] 袁鸿[1] 李小飞[1] 张学军[1] 

机构地区：[1]北京航空材料研究院,100095

出　　处：《焊接》2008年第4期45-49,共5页Welding & Joining

基　　金：国防预研基金资助项目(51418040603HK5108)

摘　　要：针对一种先进的α-β型高强钛合金(Ti-Al-Zr-Mo-Cr-Nb体系),进行了电子束焊接头组织与性能的研究。通过接头性能测试和微观组织分析,考察了固溶-时效-焊接、固溶-焊接-时效、固溶-时效-焊接-固溶-时效、固溶-焊接-β热处理4种状态下焊缝、母材及接头的拉伸性能。研究表明,该合金焊态焊缝强度非常高,而塑性很差;焊后固溶时效降低焊缝强度,但显著改善塑性;焊前固溶焊后时效使焊缝强度进一步提高,塑性则进一步恶化;焊后β退火处理则使焊缝具有较好的塑性和较高的强度,但其不足是母材的塑性严重下降。综合考虑,固溶时效接头具有较好的塑性和强度。最后结合接头显微组织分析了组织因素对接头强度和塑性的影响。Studies on the microstructures and properties of electron beam welds were conducted for an advanced high strength α-β titanium alloy,which is Ti-Al-Zr-Mo-Cr-Nb system.Tensile properties of welds,base metal and welded joints under four heat treatments were investigated.In these treatments the welds were subjected respectively to solution-ageing-welding,solution-welding-ageing,solution-ageing-welding-solution-ageing and annealing-welding-β annealing.It is revealed that the strength of the welds in as-welded condition is high,while its ductility is poor.Postweld solution and ageing can reduce joint strength and enhance its ductility obviously.Preweld solution and postweld ageing will increase joint strength further and make its ductility poorer.Postweld β annealing can result in the welds with high strength and good ductility,but it has a drawback to cause serious damage to the ductility of base metal.On the base of the foregoing thorough comparisons,it is clear that postweld solution and aging is more beneficial for the weld tensile properties.Finally the effects of microstructures on the welds strength and ductility were discussed.

关 键 词：钛合金 电子束焊 焊后热处理 力学性能 

分 类 号：TG457.19[金属学及工艺—焊接]