ゴム半球と剛平面の接触における真実接触面積の接触応力依存性とその簡易推定法

抄録

In this study, in-situ observations of a contact interface between a transparent rubber hemisphere made of PDMS (poly dimethyl siloxane) and a smooth plate made of PMMA (polymethyl methacry- late) were performed. Using a reflective optics, the space distribution of real contact regions formed in the apparent contact region was visualized. Additionally, the normal load dependence of friction force that acts on the contact interface was also investigated. As a result, it was found that the classical Amontons' friction law breaks down in this system; friction coefficient gradually decreased with increasing normal load. Based on Persson's contact theory, we discussed the mechanism of the normal load dependence of real contact area and friction coefficient. Finally, a novel method for estimating the real contact area and shear strength in sliding friction of a rubber like material was developed. The use of this method allows to estimate the real contact area and shear strength without any optical measurements of contact interfaces.