Influence of Composition of Charge Materials of Flux-cored Wires on Mechanical Characteristics and Corrosion Resistance of Electric Arc Coatings

Abstract

The influence of charge materials of flux-cored wires on their mechanical characteristics, chemical microheterogeneity and corrosion resistance in an aqueous solution of 3% NaCl was established. It is shown that, in contrast to coatings made of solid wires, coatings sprayed using flux-cored wires (PO) have a high chemical heterogeneity. This is due to the fact that the droplets that disperse from the PD melt and form a coating have different chemical compositions. This is caused by incomplete fusion of the charge and steel shell at the ends of the PD during electric arc spraying of coatings. To reduce the chemical micro-heterogeneity, it is proposed to add powders of ferroalloys FeSi, FeMn and self-flux PG-10H-01 to the charge of powder wire containing chromium, boron, carbon-containing components (Cr, FH, PG-100, B4C, FCB) between the components of the charge, homogenize the melt of PD and, as a consequence, reduce the microheterogeneity of the coatings. The presence of chromium, ferrochrome, ferro-silicon and ferromanganese in the charge of PD 90Х17РГС and PD 75Х19Р3ГС2 determines the minimum chemical microheterogeneity of coatings from these wires and, as a result, ensures their high corrosion resistance, which is close to corrosion steel18. To increase the completeness of fusion of the components of the PD charge between itself and its steel shell, it is proposed to add to the PD charge powders of ferroalloys Fe-Mn, Fe-Si, which have a low melting point, able to interact with refractory components of the charge to form low-temperature eutectics. The addition of ferro-silicon, ferromanganese and self-flux alloy PN-10H-01 powders based on ferrochrobor and ferrochrome provided high hardness of electric arc coatings, low heterogeneity in terms of chromium content in coating lamellae and, as a consequence, high corrosion resistance.