High temperature corrosion studies of cermet particle reinforced NiCrBSi hardfacings

Metal matrix composite hardfacings provide various types of heat and wear resistant products. They are widely used in high temperature aggressive environments due to their excellent high temperature corrosion and wear resistance. In this study, Cr3C2–Ni and TiC–NiMo particles were used to reinforce a NiCrBSi matrix in plasma transferred arc welding process. These cermet particle reinforced hardfacings were examined on their oxidation behaviour and high temperature corrosion in different solid salts to optimise the field of application under high temperature conditions. Corrosion behaviour in solid salts is strongly dependent on the corroding anion. Cr3C2–Ni reinforced hardfacings behave better in oxidative and sulphate/phosphate environment, while TiC–NiMo hardfacings show better resistance against chlorine and carbonate ions up to 700 °C. Additionally, oxidation is no critical exposure for these types of hardfacings.

► High temperature corrosion analysis of two novel cermet particles reinforced NiCrBSi hardfacings. ► Influence of different corrosive anions at 700 °C on the degradation behaviour ► High oxidation stability at 700 °C of both hardfacings was investigated. ► Cr3C2–Ni reinforced hardfacing resists sulphate and phosphate environments at 700 °C. ► TiC–NiMo reinforced hardfacing resists chlorine and carbonate environments at 700 °C.