Effect Of Process Parameters On The Strength Of Aluminium Alloy A5052 Sheets Joint Welded By Resistance Spot Welding With Cover Plates

Resistance spot welding (RSW) is the most popular joining technique used by automotive industries for the manufacture of automobile body structure. In automobile industries, the weight saving effect of replacing steel parts is an important factor in reducing fuel consumption and increasing speed and natural resources savings. In this study, A5052 aluminium alloy sheet having 1 mm thickness were welded using the RSW with cover plates. The process parameters namely welding current, welding time and electrode force considered for weld quality. The welded joints were subjected to tensile shear and hardness tests to determine the influence of welding parameters effect on the quality of spot welded joint. Also parameters effect on nugget diameter and failure modes were studied. The results showed that increase in welding current and weld time tensile shear strength and nugget diameter increased. While, increase in electrode force both nugget diameter and weld strength decreased. Hardness measurement results indicated that nugget diameter gave the lowest hardness value than base metal. The interfacial failure mode occurs for nugget diameter up to 5.81 mm and above this value nugget pullout failure mode observed. The result reveals that the technique is feasible to weld aluminium alloy.