Study and Analysis of Various Parameters Affecting Nugget Formation in Resistance Spot Welding Using FEM

Abstract

In this project the effect of various parameters affecting the nugget formation in resistance spot welding is
studied. Thus here we consider the material CRCA steel of grade EDD with specimen of dimension 110*30 and two
upper and lower joining sheets having thickness 0.91mm and 1.22mm respectively and welding gun of integrated type
with welding electrode of copper chromium having dome shape tip. And changing the parameters welding current, weld
time and electrode force by keeping the other parameters constant for obtaining the optimum diameter of welding
nugget. In this project Taguchi method is considered as a design of experiment in Minitab 17 software to obtain the
effective parameters from the various parameters (here the Taguchi method of Minitab software reduces the 5
3 = 125
parameters are reduced to 25 effective parameters) then experimental work are carried on that effective parameters
only. From that result one can predict the best combination of the parameters which can be validated with the
experimental work. Similar parameters and boundary conditions of the best combination are applied to the FEA model of
resistance spot welding and the analysis of that FEA model is carried out using the analysis APDL software. Then the
nugget diameter obtained during the analysis of the FEA model of RSW is compared with the resulted nugget diameter
obtained experimentally and with the predicted value of taguchi analysis.