DETECTION OF VARIOUS DEFECTS IN SUBMERGED ARC WELDING BY DYE PENETRANT AND MPI TEST

Abstract

This experimental study was carried out to analyse the effects of pulse parameters on mechanical behavior of TIG welded aluminium alloy 1100. Pulsed current gas tungsten arc welding (PCGTA) is a variant of GTA welding which involves cycling of the welding current from higher level to lower level at selected regular frequency. The main aim of pulsing is to achieve maximum penetration without excessive heat built-up. The use of high current pulses is to penetrate deeply during peak current time and allow the weld pool to dissipate some of the heat during background current duration. This variant is frequently used for the welding of aluminium alloys as it provides good control over heat input. Fractional factorial technique is used to formulate the experimental layout and to analyse the effects of pulse parameters on the properties of aluminium alloy 1100. The response factors are tensile strength, yield strength and percentage elongation, affected by peak current, background current, ...