AN INVESTIGATION OF TENSILE STRENGTH, HARDNESS AND HAZ OF DISSIMILLAR MATERIALS SS3041 & KOVAR ALLOY BY LASER WELDING

Abstract

Very less work has been done on laser welding of dissimilar material. Laser welding of KOVAR Alloy was
studied in butt welding in SS304L. In order to decrease formation of intermetallic components during laser welding,
effect of peak power, pulse duration and welding speed and was investigated. Tensile test, Hardness test and heat
affected zone test was performed to identify the effect of each parameter on the weld. Results showed that increasing
peak power (in constant pulse energy), pulse duration (in constant peak power) and welding speed (in constant pulse
energy and peak power) will decrease tensile strength. On the other hand, decreasing the mentioned parameters will
cause destructive effects such as inadequate penetration depth, spattering and cavity formation. Improvement in the
tensile strength and decrement in hardness and Heat Affected Zone was attributed to low values of intermetallic
components in weld metal.