摘要： Using a reciprocating sliding tribometer, the velocity-dependent wear behaviors of phosphate laser (PL) glass were investigated in dry and humid air. The experimental results show that the velocity dependence of wear in PL glass is very sensitive to the presence of water. In dry air, the velocity-dependent wear of PL glass shows fracture-dominated damage behavior. With increasing velocity, the Hertzian cracks increase ?rst and then tend to saturation. Simultaneously, the material-removal volume also increases ?rst and then keeps almost unchanged. However in humid air, the wear mechanism transforms into tribochemistry-controlled wear process, and almost no crack forms on glass surface for various velocities. With increasing velocity, the stress-enhanced hydrolysis becomes weaker and material-removal volume of PL glass decreases sharply. These results may help understand the surface damage and material removal of phosphate laser glass during machining and serving in various conditions.