Friction and Wear Properties of Cr-N-x Coatings for Nuclear Fuel Cladding

Friction and wear resistance are important factors that affect the selection of accident-tolerant fuel coating materials. In this study, the wear behavior of a series of Cr-N-x coatings with different N contents was investigated using a reciprocating sliding tester. The coating morphology, change in the coefficient of friction during the friction and wear tests, and wear volume after the friction and wear tests, were characterized and discussed in detail. The results show that the Cr2N coating has better anti-friction and wear resistance behaviors than the Cr and CrN coatings under anhydrous and aqueous conditions. In addition, the water environment promoted the wear of the Zr-4 alloy and Cr coatings and inhibited the wear of the CrN and Cr2N coatings. The mechanisms of friction and wear were also discussed.