Abstract
Articular cartilage plays an important role to realize low friction coefficient in wide operating condition. While there exists several frictional mode to adapt each condition, the role of the biphasic lubrication mode relatively arises in a low sliding speed condition, where the fluid film lubrication mode can not work enough. The PVA hydrogel is expected as an artificial cartilage material, which can contain plenty of water to activate the biphasic lubrication mode. In articular cartilage, the soft gel matrix is reinforced by collagen network structure to resist tensile deformation, in which the tensile stiffness of the biphasic material generates the interstitial fluid pressurization. Higher fluid load support leads lower friction coefficient because the solid-to-solid contact pressure decreases by the increased fluid pressure. In this study, we developed the fiber reinforced PVA hydrogel to enhance the fluid pressure, which can support a considerable proportion of the contact pressure as a load bearing system. The biphasic finite element analysis showed the effective enhancement of the interstitial fluid pressurization in the fiber reinforced PVA hydrogel. The fiber reinforcement maintained the fluid load support in a migrating reciprocal sliding condition. The potential of the biomimetic artificial cartilage was expected as a load bearing material.
