Avaliação de mecanismos combinados de desgaste e suas parcelas sinérgicas em superfícies revestidas com Cr3C2 pelo processo de deposição HVOF

Abstract

There is an increasing need to develop materials to solve engineering problems. The evaluation tools for these materials also need to be updated according to the demand of the properties of these materials. There is a great interest in reducing the most varied forms of material wear. Unfortunately, wear processes cannot be completely vanished. As result, some tools to recover these surfaces, such as depositions by HVOF, are in high demand at the market. This work aims to analyze how an alloy based on Cr3C2 deposited by HVOF behaves in the presence of wear generated by both corrosion and cavitation erosion, as well as the synergism generated by wear processes. Volume variation analysis was used to evaluate cavitation erosion processes and electrochemical analyzes to understand corrosion mechanisms. The volume loss values were obtained as a result, both in neutral and corrosive media. Results were also obtained from Tafel curves by open circuit potential from the samples. With these results, it was possible to conclude that the analysis by volume variation was not efficient on this work to understand wear mechanisms. Electrochemical analyzes has shown us the strong impact that eroded surface has over corrosion results. It was also possible to conclude that corrosion properties are excellent for this coating, which may has minimized the effects of volume variation, not allowing a deep analysis using this tool. It was also observed how the porosity influenced the mechanical and chemical properties of the coatings.