Research status of brazing and soldering materials for Cu-Al dissimilar metals

The research results of brazing and soldering materials for Cu-Al dissimilar joints are summarized from two aspects of fluxes and filler metals at home and abroad. The mechanism of non-corrosive fluxes and filler metals on joint bonding,interface reaction,microstructure and growth law of intermetallic compound in brazing process of Cu-Al dissimilar joints are emphatically introduced. Nevertheless,there are some problems as follows in the application of brazing and soldering materials for Cu-Al dissimilar joints. The melting temperature and price of noncorrosive are both high and its scope of application is narrow. The melting temperature of Al-Si brazing filler metals is high and it makes aluminum alloys easy to corrode. The low cleanliness of brazing and soldering filler metals makes seam easy to appear oxidation inclusions,which affects the mechanical properties of the joint.