Dissimilar metals AISI 304 steel and AA 2219 aluminium alloy joining by friction welding method

Abstract

Abstract Welding of dissimilar metals is very much interested in industrial applications. In dissimilar metals in particular light weight metals aluminium alloy in combination with steel is advantage in automotive and aerospace industries. Welding of aluminum alloy and steel is a great challenge because of their different thermal and metallurgical properties. In this present work the joining of dissimilar metals AISI 304 steel and AA2219 aluminium with continuous drive friction welding method is used for study. This solid state welding process can be done with minimum heat affected zone so that the properties of metals cannot change. In this method because of friction heat will generate and the metals at the interface become plasticized and it was forged to weld. The welding process was done with different process parameters, rotational speed, friction pressure, upset pressure and burn of length was selected as per the previous study. The friction time kept constant for all welding joint samples. The experimental results were analyzed by means of tensile test, Vickers micro hardness test and microstructure. The strength of the joints varied with increasing friction pressure and more influenced by upset pressure. As the friction pressure and upset pressure increases the flash increases with brittle fractures at the joint interface. The welding progresses from the outer to the inner region and the intermediate compounds are formed. The optical microscope observation and SEM analysis is done for microstructure characterization. The intermetallic compounds FeAl are observed at the inter face. The elemental composition was also analyzed by EDX technique. The solid state welding enables to join dissimilar metal combination of ferrous and non ferrous metals which are difficult in conventional fusion welding methods.