Effect of Deposition Temperature on the High‐Temperature Corrosion Resistance of CrMoNbZr Medium‐Entropy Alloys Coatings

Abstract

A near‐equimolar CrMoNbZr coating with low thermal neutron cross sections is prepared on zircaloy‐4 substrate by radio frequency magnetron sputtering. The microstructure, mechanical properties, and surface wettability of the coatings prepared at different deposition temperatures are studied. The high‐temperature corrosion resistance of the CrMoNbZr coatings is investigated by a 40 d autoclave corrosion test with pure water containing 3.5 ppm lithium, 1000 ppm boron at 320 °C. The results indicate that the CrMoNbZr coatings are mainly composed of body‐centered cube‐structured nanocrystals, and the coating deposited at 300 °C has superior high‐temperature corrosion resistance and mechanical properties. Finally, the mechanism of high‐temperature corrosion is elucidated.