Ag interlayer's influence on microstructure and mechanical properties of laser-welded Ta/304L joints

Tantalum and 304L possess unique properties for aerospace applications. Ta offers high temperature and acid/alkali resistance, while 304L is cost-effective with excellent corrosion resistance. Joining Ta and 304L optimises design, lowers costs and meets specific requirements. This study examined laser lap welding of 0.6 mm Ta and 304L with/without silver interlayer. Joint structure and properties were analysed to reveal the influence of detrimental phases, with first principles calculations for TaFe 2 and TaCr 2 . Without Ag interlayer, the joint had 1857.19 N tensile shear force and 530 HV average weld zone hardness. Adding Ag reduced TaFe 2 formation, improving tensile shear strength to 2100.30 N with 460 HV average hardness. First principles calculation confirmed TaCr 2 's superior phase stability over TaFe 2 .