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Three-Dimensional Plasto-elastohydrodynamic Lubrication (PEHL) Model for Mixed Lubrication


Surface contact and relative motion are commonly seen in all machine systems. Under mixed lubrication, direct surface asperity contact often results in high local contact pressure and subsurface stress that far exceeds the yield strength of material, causing surface plastic displacement and subsurface plastic strain. The plastic strain will modify the contact surface profile, introduces residual stresses, and may also alter material properties through work-hardening. The modified surface profile and residual stresses can lead to changes of local pressure and stresses, as well as the lubrication status. The Three-Dimensional Plasto-elastohydrodynamic Lubrication (PEHL) Model targets these issues and makes this type of model-based simulation closer to reality.

Address Goals

A surface pair under contact and relative motion with or without lubrication forms a tribological interface. Generally speaking, friction and wear are inevitable because relative motion and rubbing are everywhere and in all mechanical systems. Excessive surface pressure and subsurface stress are among the primary factors causing wear and failure of machine elements. Wear induced material loss may alter designed surfaces and change the interface performance. This model, and the model-based simulation, is a significant step toward the practical simulation of component working status because it can provide accurate information about the pressure distribution, film thickness profile, subsurface stress field, and plastic strain for surfaces under a mixed lubrication contact, which are essential to further analyses of friction, wear, and contact fatigue, as well as accurate design of energy efficient and durable systems.