Oxidation control in arc-sprayed SS420 coating

Abstract

In coating, especially in the arc spraying process, oxidation leads to the deterioration of wear and corrosion-resistant properties. In the present work, an effective shrouding arrangement is designed and introduced to arc spray gun to reduce oxidation content in the coating. The effect of shrouding on microstructural and coating properties is analysed by the characterization techniques, such as SEM, EDS, XRD and Vickers microhardness testing. Adhesion strength and fracture toughness were also measured. Results showed that almost 70% oxidation reduction is found in as-sprayed coating. It is concluded that the shrouding attachment increases inter-splat cohesion, adhesion strength and also produces coatings with optimum oxide content and porosity. Furthermore, On the contrary, corrosion resistance of air-atomized coatings was found better than nitrogen-atomized coatings owing to oxide phase formation.

Effect of burnishing on HVOF coated boiler steel against hot corrosion in actual boiler environment

“…Cross-sectional EDAX analysis showed that applied coating splat boundaries were rich in chromium oxide owing to selective oxi- [63][64][65]. The protective oxides tend to develop at splat boundaries and perform the role of barricade against the inward dissemination of corroding species [66]. Figure 9 shows the most likely hot corrosion process of burnished-coated specimens in a 1000-hour coalfired boiler.…”

“…The protective oxides tend to develop at splat boundaries and perform the role of barricade against the inward dissemination of corroding species [66]. Figure 9 shows the most likely hot corrosion process of burnished-coated specimens in a 1000-hour coal-fired boiler.…”

Corrosion resistance of NbN and NbxAlyN coatings on stainless steel

“…An equal 3-electrode cell apparatus and stabilization period was employed in the potentiodynamic polarization tests. Starting from −30 mV below the OCP, the potential was swept at a scanning rate of 1 mV s −1 [16][17][18][19]. Potentiodynamic tests were performed in triplicates.…”

HVOF Deposition, comparative investigation and optimum selection of molybdenum, boron, chromium, and titanium in Iron amorphous composite coatings

“…The most common method for the spraying of Iron alloys and amorphous composite coatings is the thermal spraying technique. Some of the thermal spraying techniques are arc spraying (AS) [1], high-velocity oxy-fuel spraying (HVOF), plasma spraying (PS), and high-velocity air-fuel spraying (HVAF) [2]. HVOF indicated superior performance as compared to arc spraying and plasma spraying.…”