Pulsed Current GMAW for Superior Weld Quality of Austenitic Stainless Steel Sheet

Pulsed Current Gas Metal Arc Welding under Different Shielding and Pulse Parameters; Part 1: Arc Characteristics

“…This is corroborating some earlier reported works 5,8,11) where it is proposed that a comparatively higher f and I m can be satisfactorily used in joining of mild steel.…”

“…[4][5][6][7][8][9][10] But it is often pointed out that the quality of P-GMA weld very much depends upon arc characteristics [11][12][13][14][15] affecting the energy distribution in welding dictated by the pulse parameters and shielding environment. However, the thermal behaviour of weld depending upon arc characteristics significantly influences the chemistry, microstructure and stresses of the weld.…”

“…16,17) It involves the pulse parameters as mean current (I m ), pulse current (I p ), base current (I b ), pulse time (t p ), base time (t b ) and pulse frequency ( f ) as well as arc voltage (V). However, the difficulties in controlling the pulse parameters with respect to appropriate operation of P-GMAW process have been well addressed by considering a summarized influence of pulse parameters defined by a hypothetical factor fϭ[(I b /I p )ft b ] derived from the energy balance concept [1][2][3][4][5]9,11,12,[18][19][20] where, t b ϭ[(1/f)Ϫ t p ]. It may be considered that the use of P-GMAW by right selection of pulse parameters confirming the desired f can provide intended quality in weld fabrication.…”

“…However, the thermal behaviour of weld depending upon arc characteristics significantly influences the chemistry, microstructure and stresses of the weld. [2][3][4][5] The difficulties in right selection of pulse parameters to control all these phenomena often restricts the wide application of this process in weld fabrication of different materials due to paucity of detail knowledge of the arc characteristics in P-GMAW process. The control of arc characteristics by appropriate selection of pulse parameters in P-GMAW process is quite critical due to simultaneous influence of relatively large number of parameters on each other during welding.…”

Arc characteristics and behaviour of metal transfer in pulsed current GMA welding of stainless steel

“…This is corroborating some earlier reported works where it is proposed that a comparatively lower , I m and arc voltage can be satisfactorily used in joining of thin sheets (Ghosh et al, 2007b), whereas an intermediate range of I m and arc voltage with lower which provides comparatively lower energy input should be used for joining of thick sections considering the facts that lower gives higher arc stiffness and droplet velocity (Ghosh et al, 2006).…”