Effect of abrasive particle degradation on tribochemical wear of monocrystalline silicon

Abstract

Wear and adhesion modification of Si/SiO2 rubbing pair surface were investigated through nanowear experiments of silicon against a spherical SiO2 probe in air and water to clarify the degradation mechanism of SiO2 particles at the tribochemical reaction interface. The result showed that the major material removal occurred on the silicon substrate surface while the wear of the SiO2 tip was slight and negligible. The tribochemical reaction products attached to the surface of the SiO2 tip and changed the interfacial contact size. Once in water environment, the adhesion modification of wear debris on the top of SiO2 tip might cause the abrasive particle degradation, wherein the silicon surface presented a wearless and lubrication state. Analyses indicated that the degradation behavior of SiO2 particle can be attributed to the shedding of wear debris due to the real shear interface transferred from the silicon substrate to the modified layer of the tip. The SiO2 particle degradation in the tribochemical wear progression was dependent on the transfer mechanisms of the tribochemical products in different environments. Therefore, adjusting the environmental parameters may be the effective means to prevent the wearless friction behavior of silicon material during the nanomanufacturing.