Study on formation of intermetallic compound layer during aluminium to steel dissimilar joining: A Review

Use of lightweight metals in automobile industry is viable approach to enhance fuel efficiency and reduce CO2 and unhealthy gas emissions. Automotive manufacturers focused on reducing weight of vehicle and aluminum especially used as best alternative to steel for car body structure. It is not possible to replace steel by Aluminum completely due to safety and strength constraints of the automotives. Joining of Aluminum to steel face difficulty due to their incompatible thermophysical characteristics. At the aluminium to steel brazing interface, formation of brittle intermetallic compound layer composed with Al rich phases on Al side like FeAl3, Fe2Al5 and Fe rich phases on steel side Fe3Al, Fe3Al2 etc. Al rich phases FeAl3, Fe2Al5 shows needle like structure.