MAG WELDING OF LOW CARBON STEEL PROFILES

Nowadays, the GMAW welding represents the most used welding technology in a variety of industrial applications due to the easy automatization of the process and to the overall welding quality.

This paper highlights the differences between various GMAW processes. Pulsed MAG and CMT (cold metal transfer) MAG welding are compared in order to determine the best technique for welding of thin steel profiles. Welding of low carbon steel profiles are realised using different process parameters and welding conditions. The welded samples are characterised trough optical and SEM microscopy revealing the influence of the heat input on the microstructure of the weld bead. Moreover, the heat distribution during the welding process is analysed by means of a FLIR thermal camera showing the benefits of the CMT welding process. The mechanical behaviour of the welded joints is characterised by microhardness and tensile testing.