Various filler metals have been devised to
apply for this brazing technique. First attempt was
carried out using a paste type filler material. The aluminum alloy (Al-12Si) was grounded down to a few micro size and mixed with flux, which turned into the paste type filler metal. The other approach was using thin sheet of an aluminum alloy (Al-12Si) with thickness of 0.7 mm. The sheet type filler metal was placed between aluminum and steel sheet as shown in Fig. 7.The sheet type filler metal was incorporated with flux before executing resistance spot brazing.