A sphere impacting a plate is different from half-space bulk, because energy in the former case can be dissipated form of flexural wave propagating on plate. Such loss by elastic explained Zener model; however, this model only valid for low-velocity impact with Hertzian contact law. For high-velocity plasticity, not any ore dissipation plasticity may take large fraction, so that model, which ig...

A wear prediction model is built to research the of curved switch rail in a high-speed turnout. The Archard used analyze profile evolution law. non-Hertzian contact Kik–Piotrowski method based on virtual penetration as algorithm for model. dynamic vehicle–curved system predicted profiles and measured wheel with different stages established. effect profiles’ vehicle performance analyzed. results...

| Gear theory is reexamined and we nd optimal shapes for gears. As optimality criteria, we allow: (1) minimal frictional losses (highest eeciency) assuming linear law of friction or (2) uniform maximum stress (it will wear out slowly and last the longest) assuming Hertzian contacts or (3) uniform maximal temperature, assuming we are in a high power limit in which all heat is removed by the lubr...

We study localized waves in chains of oscillators coupled by Hertzian interactions and trapped in local potentials. This problem is originally motivated by Newton’s cradle, a mechanical system consisting of a chain of touching beads subject to gravity and attached to inelastic strings. We consider an unusual setting with local oscillations and collisions acting on similar time scales, a situati...

Contrast in the phase response of intermittent-contact atomic force microscopy (IC-AFM) reveals in-plane structural and mechanical properties of polymer monolayers. This result is unexpected, as IC-AFM has previously only been considered as a probe of out-of-plane properties. Until now, AFM measurements of nanoscale in-plane properties have employed contact mode techniques. In-plane property me...

The amount of heat transferred by conduction during the impact of a spherical particle with a surface depends on the thermophysical and mechanical properties of the two colliding media. Other factors, such as the surface properties (e.g. roughness, contamination, stress state, radius of curvature) and the velocity and direction of the impact, also influence the heat transfer. The available theo...

A numerical model for rolling contact fatigue has been developed using finite element method and the Tanaka-Mura micromechanical to calculate crack threshold. Two different approaches are compared: macroscopic modeling mesoscopic which considers a Voronoi polycrystalline geometry. Smooth dented surface contacts considered methods computing shear stress compared. It is shown that length scale co...

This paper presents the responses of the railway vehicle and track components in terms of contact forces and displacements. The considered vehicle model is a five-DOF pitch-plane lumped parameter quarter car model supported on two-dimensional track systems comprising three layers. The car body is linked with the vehicle bogie through secondary suspension springs and damper elements, which is fu...

Instrumented contact experiments are performed on three metallic glasses to systematically study shear band formation near a stress concentration. The results suggest that high local stresses at a point in the glass are insufficient to initiate a shear band. Rather, the yield strength must be exceeded along the entire length of a viable shear path in order for a shear band to form. Because of t...