TC18钛合金手工TIG焊与电子束焊焊接接头的组织与性能对比

Comparison of microstructure and properties of TC18 titanium alloy joint between manual TIG welding and electron beam welding

进行了TC18钛合金手工TIG焊和电子束焊工艺试验,对该合金在两种不同性能焊接工艺下焊接接头的组织和性能进行对比分析。结果表明,在相同的热处理条件下,TC18钛合金TIG焊焊缝得到口基体上分布着片状α组织,接头强度达到母材的80.5%,断后伸长率为母材的23.6%,焊缝具有较高的冲击性能,达到母材的95.2%,其热影响区的韧性为母材的44.7%;电子束焊焊缝得到β晶粒内分布着短片状α相组织,其接头强度与母材等强,断后伸长率为母材的29.7%,焊缝与热影响区具有相同水平的冲击性能,分别达到母材的55.5%和55.8%。

Technology experiments of manual TIG welding and electron beam welding TC18 titanium alloy were performed.The microstructure and properties of the two welded joints were compared and analyzed.The results showed that with the same heat treatment,the microstructure of TIG welded joint with TC18 titanium alloy was flake α phase on the base of β phase.The strength of the joint reached 80.5% of the base metal, and the elongation was 23.6% of the base metal.The joint had the high impact toughness,which reached 95.2% of the base metal,but the impact toughness of HAZ seriously decreased and only reached 44.7% of the base metal.The microstructure of electron beam welded joint was short flake α phase in β grain.The joint possessed the same strength as the base metal,and the elongation was 29.7% of the base metal.The weld metal had the same impact toughness level as HAZ,which respectively reached 55.5% and 55.8% of the base metal.