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The concept of light weight, fuel efficient, environmentally friendly and safety
in automobile has raised the use of Aluminum alloys and their joining through
resistance spot welding process for mass production. This study focuses on the
orthogonal optimization of process parameters for Resistance Spot Welding (RSW) of
Al 5052-H32 and AL 3003-0 hybrid structure in automobile / aerospace vehicles.
Taguchi L9 orthogonal array was used to design the welding experiments. Welding
current, welding time and electrode force are used as input parameters and maximum
tensile shear strength (TSS) is used as output parameter. Welding parameters are
optimized to achieve spot joint without expulsion and crack having suitable nugget size.
Optical microscopy is used to study the nugget size through macrographs of the weld
joint and microstructure of the nugget, HAZ and base material. Microhardness test and
tensile shear test are performed to evaluate the strength and failure behavior of the weld
joints. Maximum TSS achieved 91.7 MPa at 32 kA, 80 ms and 5.5 kN of welding
current, welding time and electrode force respectively with button pull out failure.
Taguchi L9 analysis gives optimized parameters as 34 kA welding current,
80 ms welding time and 5.5 kN electrode force. ANOVA result shows that welding
current has highest effect on weld tensile shear strength followed by welding electrode
force and weld time.