Dissimilar fusion welding of AA7020/MMC reinforced with Al2O3 particles. Microstructure and mechanical properties

Metal matrix composites reinforced with Al2O3 particles combine the matrix properties with the ceramic properties of the reinforcement. However, its wide application as structural materials need of the proper development of their joining processes. The present work describes the results obtained from microstructural (Optical and scanning electron microscopy and electron probe microanalyser) and mechanical evaluation (hardness and tensile tests) of aluminum matrix composites (AA7005) reinforced with 10% vol. fraction Al2O3 particles (W7A10), welded to the unreinforced alloy AA7020 (Al–Zn–Mg), using metal inert gas welding process using ER4043 (Al–Si) and ER5356 (Al–Mg) as fillers. The thermal effect of welding on different types of joint results in a loss of the mechanical properties in the heat affected zones. These properties could be recovered with post-welding heat treatments.