Arc Stability of Pulse Current Gas Metal Arc Welding of Low Alloy Steel under Different Pulse Parameters and Shielding Gas Compositions

The arc stability and performance of pulse current gas metal arc welding (P-GMAW) process under different pulse parameters (considered as their summarized influence defined by a factor Φ and shielding gas compositions have been studied through an analysis of irregularity in pulse waveform during weld deposition of low alloy steel. The arc stability has been primarily analysed as average number of peaks (N_PAJ shooting above an arbitrarily defined current (I_S) at a given interval of arcing, average deviated current (I_DC) defined as summation of shooting peak current (I_SP) beyond the I_S per peak of instability, average time interval of deviated current (T_IDC) and average duration of deviated current (T_DDC). The performance of the P-GMAW process has been analyzed with respect to its response to short circuiting. The effect of pulse parameters has been analyzed as a function of Φ, I_m and arc voltage and the shielding gas compositions has been studied with varying content of CO₂ in An It is observed that the arc stability and performance of the P-GMAW power source significantly vary with the change of pulse parameters and CO₂ content of argon gas shielding. A relatively higher Φ, I_m and arc voltage and low CO₂ content of Ar gas shielding provides better arc stability with low short circuiting.