Wear limits the life-span of many mechanical devices with moving parts. To reduce wear, lubricants are frequently enriched with additives, such as zinc phosphates, that form protective films on… (More)
Using a theoretical approach and computer simulations, we calculate the normal stiffness K(perpendicular) and the transverse stiffness K(parallel) of the interface between two contacting isotropic… (More)
The total elastic stiffness of two contacting bodies with a microscopically rough interface has an interfacial contribution K that is entirely attributable to surface roughness. A quantitative… (More)
Polymer brushes lead to small friction and wear and thus hold great potential for industrial applications. However, interdigitation of opposing brushes makes them prone to damage. Here we report… (More)
Assigning effective atomic charges that properly reproduce the electrostatic fields of molecules is a crucial step in the construction of accurate interatomic potentials. We propose a new approach to… (More)
Contact between an elastic manifold and a rigid substrate with a self-affine fractal surface is reinvestigated with Green’s function molecular dynamics. The Fourier transforms of the stress and… (More)
Discrete sine-Gordon (SG) chains are studied with path-integral molecular dynamics. Chains commensurate with the substrate show the transition from pinning to quantum creep at bead masses slightly… (More)
Friction is a well-known, but poorly understood, phenomenon that affects virtually all aspects of daily life. In some cases, friction is desirable, e.g., high friction in clutches leads to the… (More)
Structural, thermomechanical, and dynamic properties of pure silica SiO2 are calculated with three different model potentials, namely, the potential suggested by van Beest, Kramer, and van Santen… (More)
It was found recently that two polymer brushes in a tribological contact do not interdigitate when each polymer brush has its own preferred solvent, leading to low friction and low wear rates. Here,… (More)