Abstract The microstructure traits and structural integrity of Ti-6Al-4 V welds of 5 mm thickness are discussed. The use of activated flux in the tungsten inert gas (ATIG) welding technique is adopted in this study using the oxide surfactant. Bead on trials attested that the depth of penetration (DOP) is enhanced with a corresponding rise in welding current upon the use of oxide surfactant. Microstructure studies depicted the presence of acicular α’ structure of martensitic needles and Widmanstatten α platelets with β-Ti grain boundaries throughout the fusion zone. Tensile studies indicated that the strength of the joints of ATIG welds was better, as the failures were experienced in the parent metal. The impact toughness of the ATIG weldments was insignificantly reduced when compared to the base metal owing to the coarsened grains in the weld zone. The findings of this study attests the use of low cost welding technique for joining Ti-6Al-4 V of 5 mm thickness for improved properties.

中文翻译：

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s活性焊剂对Ti-6Al-4V TIG焊缝熔深、组织和力学性能的影响

摘要 讨论了5 mm 厚Ti-6Al-4 V 焊缝的显微组织特征和结构完整性。在使用氧化物表面活性剂的本研究中，在钨惰性气体 (ATIG) 焊接技术中使用活化焊剂。焊道试验证明，使用氧化物表面活性剂后，熔深 (DOP) 会随着焊接电流的相应增加而增强。微观结构研究描述了在整个熔合区存在马氏体针状和 Widmanstatten α 片状晶界的针状 α' 结构，β-Ti 晶界。拉伸研究表明，ATIG 焊缝接头的强度更好，因为母材发生故障。与母材相比，由于焊接区晶粒粗化，ATIG 焊件的冲击韧性没有显着降低。