Effects of humidity and counter-surface on tribochemical wear of soda-lime-silica glass

The effects of counter-surface chemistry on the friction and wear of soda-lime-silica glass were investigated using a ball-on-flat tribometer with various ball materials (stainless steel, silicon nitride, and alumina) in dry and humid environments. It was found that the interfacial wear was very sensitive to environmental humidity and counter-surface chemistry. In dry conditions, soda-lime glass was damaged mechanically regardless of counter-surface materials, creating a rough and deep wear track. These results were consistent with the Archard relationship-a softer material would wear mechanically by a harder material. However, in humid conditions, the ball materials that were harder than the soda-lime glass were damaged. Thus, the wear of glass interfaces under humid conditions does not follow the Archard relationship. These results clearly show that the tribochemical reactions involving the substrate and counter-surface chemistry as well as the adsorbed water molecules are determining factors governing wear behaviors in humid environments.