In order to determine weld quality of dissimilar materials,
the strength of weldment was also determined. Structures
employing spot weld are usually designed so that
the welds are loaded in shear when the parts are exposed
to tension or compression loading. In some cases, the welds
may be loaded in tension, where the direction of loading is
normal to the plane of the joint, or a combination of tension
and shear [1]. In this study, at a welding time of
17 cycles (1 cycles = 0.02 s) and electrode force of 6 bar,
the effects of peak weld current, on the tensile shear
strength bearing capacity of the dissimilar materials weld
are given in Table 3. Results are also shown graphically
in Fig. 5
between the nugget sizes comes from the different diameters
of electrodes. In addition, it was also found that the weld
nugget lost its symmetric form because of the unbalanced
heat resulting from different physical properties of the steel
sheets. As known the heat balance may present a problem
when spot welding together unequal thickness of the same
metal, equal thicknesses of two metals with a significant
difference in electrical conductivities, or a combination of
the two. Electrode configurations and compositions can
be used to overcome unbalanced heating to some extent
[1]. IF 7114 steel side of welded materials was observed
deep electrode indentation rather than austenitic stainless
steel side due to low yield strength of IF steel. The yield
and tensile strength of base materials were given in Table 3.