Running-in of a double network gel for low friction in water

Abstract

This study aims to clarify the potential of double network (DN) gel to realize low friction coefficient under water lubrication environment. Friction tests were carried out by using DN gel film and silicon carbide (SiC) disk in water. DN gel shows running-in behavior consists of lowering friction coefficient twice, then friction coefficient shows less than 0.001 under limited experimental conditions. By introducing in-situ test apparatus, self-formation of damaged region is confirmed and external water penetrates into self-formed damaged region. As a result, damaged region becomes water-rich situation more and more and formation of lubricious water layer is enhanced gradually. Thus running-in behavior occurs by friction system using DN gel.