The Effect of Powders of Refractory Materials on the Transfer of Electrode Metal and the Structure of Welds of Low-Carbon Low-Alloy Steels

This article is devoted to studies of the effect of powders of refractory materials on the structure and mechanical properties of the deposited metal of welds of low-carbon low-alloy high-strength steels, as well as on the nature of electrode metal transfer during welding. It was found that the addition of WC, VC, TiC powders to the main coating of welding electrodes reduces the size of droplets of electrode metal by 14-17 % at a current of 110 A. It is shown that the macrostructure of welds of low-carbon low-alloy high-strength steels made using experimental electrodes is characterized by the presence of a large crystalline structure. The metal crystallites of the welds made with inoculating additives assumed a more stable state, and their maximum cross-sectional area decreased by 6-8 times compared to the base sample. The microstructure of the weld metal is characterized by the presence of finely dispersed ferrite-bainite of predominantly needle-like morphology. It is shown that the addition of refractory materials to the electrode coating led to an increase in the values of temporary resistance, yield strength, and Vickers hardness of the weld metal. At the same time, there is a decrease in the level of impact strength by 1,5 - 3 times, depending on the type of powder additive.