Influence Of Different Microstructural Features On Wear And Corrosion Resistance Of 13cr Steel Arc Sprayed Coating

Wire arc spraying process is a classical technique to deposit thick coatings using metallic wires as feedstock. The process is used to protect mechanical components against wear and corrosion. 13Cr steel coatings were produced using wire arc spray with different spray distance gunsubstrate. Coatings microstructure was investigated using optical microscopy and scanning electronic microscopy (SEM). Chemical composition were determined using EDS analysis. The coatings exhibit a layered microstructure consisting of 13Cr steel lamella and FeO veins between them including cracks and pores. Porosity and lamella thickness were determined by image analysis. Mechanical properties were evaluated by microhardness Vickers. The wear test was conducted by mean of ball-on-disc apparatus according to ASTM G99 standard. Corrosion resistance was analysed with electrochemical polarization test in 3% NaCl solution. The results show that corrosion resistance is strongly influenced by porosity which accelerate corrosion leading to depletion of lamellae forming the coating. However, coating post-treated with an epoxy sealing present a good corrosion resistance.