Nanoscale Wear Triggered by Stress-Driven Electron Transfer

Wear of sliding contacts causes device failure and energy costs; however, the microscopic principle in activating wear of the interfaces under stress is still open. Here, the typical nanoscale wear, in the case of silicon against silicon dioxide, is investigated by single-asperity wear experiments and density functional theory calculations. The tests demonstrate that the wear rate of silicon in ambient air increases exponentially with stress and does not obey classical Archard's law. Series calculations of atomistic wear reactions generally reveal that the mechanical stress linearly drives the electron transfer to activate the sequential formation and rupture of interfacial bonds in the atomistic wear process. The atomistic wear model is thus resolved by combining the present stress-driven electron transfer model with Maxwell-Boltzmann statistics. This work may advance electronic insights into the law of nanoscale wear for understanding and controlling wear and manufacturing of material surfaces.

Automated summary

This study investigates the nanoscale wear process between silicon and silicon dioxide through experiments and calculations. The results show that the wear rate of silicon in ambient air increases exponentially with stress and does not follow the classical Archard's law. Atomic-level wear model calculations reveal that mechanical stress linearly drives electron transfer, activating the sequential formation and rupture of interfacial bonds in the atomistic wear process. This work is important for understanding and controlling wear and manufacturing of material surfaces.