Impact of dissolved oxygen concentration on the coupling damage between fretting wear and corrosion on zirconium alloy cladding tube in high temperature pressurized water

Grid-to-rod fretting wear behavior of zirconium (Zr) alloy tube under gross slip regime in high temperature pressurized water with varying levels of dissolved oxygen (DO) was studied. The results indicated that the removed material volume and wear depth of the Zr alloy tube gradually increased with rising DO concentration. The increasing of third-body layer thickness had little influence in fretting damage. Corrosion could promote fretting wear by the acceleration of delamination crack propagation. Moreover, the synergistic interaction between fretting wear and corrosion would cause the crevice corrosion and under-deposit corrosion in unworn area. In addition, the coupling damage mechanism of fretting wear and corrosion was explored.