Joining technology of dissimilar metals is very important in the manufacturing field. However, it was difficult to join dissimilar metals because intermetallic compounds are formed at the joining interfaces. On the other hand, spot brazing can be used to join quickly by using resistance heating. The formation of intermetallic compounds can be prevented. When brazing dissimilar metals, the selection of brazing filler metal is very important. However, there is no brazing filler metal that can be assumed to be able to join dissimilar metals. In this study, the joining of dissimilar metals as done by spot brazing with a combination of filler metals. Combination brazing filler metal was defined as a suitable brazing filler metal for CP-Ti combined with a suitable brazing filler metal for stainless steel. Brazing ability of dissimilar metals was investigated by observation and analysis. Commercial pure titanium (CP-Ti) and stainless steel SUS304(JIS) were used as dissimilar base metals. Ag-based brazing filler metal foil (BAg-8) and Ni-based brazing filler metal foils were used. Brazing was done with a micro spot welder under an Ar gas atmosphere. Brazing conditions were 600 A as brazing current and 2 seconds as brazing time. Brazing ability was estimated by tensile shear strength, cross sectional microstructure observation, and elemental distribution using EPMA examinations. CP-Ti and SUS304 could be joined by spot brazing with BAg-8 and Ni-based brazing filler metal foils. As compared with BAg-8, in which case a combination of BAg-8 and BNi-6 was used, high joint strength was obtained.
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