An investigation on metallurgical and mechanical properties of vacuum brazed Ti-۶Al-۴V to ۳۱۶L stainless steel using Zr-based filler metal

Both Ti-۶Al-۴V and ۳۱۶L stainless steels are widely used as engineering alloys. Fusion welding of these two alloys is not easily possible due to their incomplete solubility in each other. Brazing is one of the best choices for joining dissimilar alloys. In this study, wettability experiments were done at ۹۴۰ and ۹۷۰ ºC for ۵, ۱۵ and ۳۰ min. Also, joining of these two alloys was carried out at ۹۴۰ and ۹۷۰ ºC for ۱۵ min. Optical and scanning electron microscope (SEM) were used for metallurgical observations. Moreover, mechanical properties of the brazed joint were investigated using microhardness test. The results showed that some reaction layers were composed in the brazed joint’s cross section. Ni-Ti intermetallic compounds were also observed in the brazed joint. Investigation of mechanical properties showed that hardness in the joint’s center is higher than base metals.