Time-Resolved Dynamic Friction Testing of a Polyurethane Foam Against a Polymer/Clay Nano-composite Under Impact Loading

摘要

A new method based on the split Hopkinson pressure bar was developed to test the dynamic friction under impact loading. Time-resolved dynamic friction coefficient of a polyurethane foam against a polymer/clay nano-composite (PCN) was tested with the use of the new setup. In the experiments, the friction pair can be loaded by normal pressure and friction force simultaneously, and the time-resolved dynamic friction coefficient can be obtained without any assumptions and theoretical derivations. In addition, the interfacial slipping velocity was measured by a specially designed optical device. Two groups of dynamic friction experiments of polymer/PCN pairs were implemented, in which the effect of surface conditions and loading conditions was evaluated. The results show that the effect of surface roughness is obvious, while that of loading is unobvious.