Microstructure of low-carbon steel wire and its welding and fabrication properties

Abstract

In this paper, we researched the impact of wire rod structure homogeneity on arc stability of welding wire. The microstructural analysis was carried out for low-carbon welding wire in its sections with steady and unsteady arc burning and it showed that equal distribution of carbide phase in ferrite matrix complied with the best arc burning. The presence of coagulated carbides in microstructure was typical for sections with unsteady arc burning. The results of Vickers hardness measurement evidenced that the best arc burning was appropriate for wire samples, characterized by increased and steady hardness. The increased welding wire porosity could be caused by presence of gases in it (the increased concentration of nitrogen was found there) and it stipulated wire hardness decrease and unsteady arc burning as a result.