Negative thermal expansion induced suppression of wear in dry sliding friction

Abstract

Surface temperature is among crucial factors, which control wear during sliding dry contact. Using computer modeling, we study the possibility to achieve close to zero rate of surface wear during sliding friction of the special type of materials, which possess negative thermal expansion. The numerical simulations reveal two wear regimes for negative thermal expansion materials as dependent on the applied normal stress level. When the applied stress is lower than that of a critical level, a steady almost zero wear rate and nanorough surface are achieved during friction. Otherwise, wear rate is of the same order of magnitude as for positive thermal expansion materials. The critical stress value is analyzed as depending on the material's mechanical, thermophysical, and surface roughness characteristics.