Breakdown of Reye's theory in nanoscale wear

Abstract

Building on an analogy to ductile fracture mechanics, we quantify the size of debris particles created during adhesive wear. Earlier work suggested a linear relation between tangential work and wear debris volume, assuming that the debris size is proportional to the micro contact size multiplied by the junction shear strength. However, the present study reveals deviations from linearity. These deviations can be rationalized with fracture mechanics and imply that less work is necessary to generate debris than what was assumed. Here, we postulate that the work needed to detach a wear particle is made of the surface energy expended to create new fracture surfaces, and also of plastic work within a fracture process zone of a given width around the cracks. Our theoretical model, validated by molecular dynamics simulations, reveals a super-linear scaling relation between debris volume ($V_d$) and tangential work ($W_t$): $V_d\sim W_t^{3/2}$ in 3D and $V_d\sim W_t^2$ in 2D. This study provides a theoretical foundation to estimate the statistical distribution of sizes of fine particles emitted due to adhesive wear processes.

References in corpus (7)

• A parameter-free mechanistic model of the adhesive wear process of rough surfaces in sliding contact
• Effect of wear particles and roughness on nanoscale friction
• The role of interfacial adhesion on minimum wear particle size and roughness evolution
• Creation and evolution of roughness on silica under unlubricated wear
• Adhesive wear and interaction of tangentially loaded micro-contacts
• Variational phase-field continuum model uncovers adhesive wear mechanisms in asperity junctions
• A criterion for critical junctions in elastic-plastic adhesive wear

Cited by in corpus (1)

• Roughness evolution induced by third-body wear