Fretting Corrosion Performance Evaluation of Uncoated Cladding, Cr Coating Cladding and AlCrNbSiTi Coating Cladding

Abstract

In pressurized water reactors (PWRs), flow-induced vibration (FIV) induces the fretting wear of fuel rods and supporting grids, and the process is accompanied by corrosion, which is called fretting corrosion. In this paper, fretting corrosion experiments were carried out in a simulated cladding service environment, and the fretting corrosion performance of AlCrNbSiTi coating cladding, Cr coating cladding and uncoated cladding with the supporting grids were investigated using a three-dimensional white light interferometer and a scanning electron microscope (SEM). The results showed that the AlCrNbSiTi coating cladding has the strongest fretting corrosion performance, the Cr coating cladding has the second best fretting corrosion performance and the uncoated cladding has the worst fretting corrosion performance. The coating also changes the wear mechanism of the cladding and improves the corrosion resistance of the cladding, which is responsible for the improvement in the fretting corrosion performance of the cladding. By comparing the AlCrNbSiTi coating with the Cr coating, it was found that the AlCrNbSiTi coating has a better fretting corrosion performance than the Cr coating due to its higher hardness and stronger corrosion resistance.