Tensile and tribological properties of polytetrafluroethylene homocomposites

Polytetrafluoroethylene (PTFE) fiber and fabric homocomposites consisting of a PTFE fiber/fabric reinforcing element and a PTFE matrix were fabricated. The tensile and tribological properties of PTFE homocomposites were tested. It is found that the self-reinforcements have improved the tensile and tribological properties of PTFE significantly. PTFE fiber homocomposite with 40 wt% fiber (IH40) performed the best among the fiber homocomposites. The tensile strength of IH40 was twice that of the unfilled PTFE. Compared to the unfilled PTFE, the friction coefficient and wear rate of IH40 decreased 11% and 53%, respectively. PTFE fabric homocomposites behaved better than fiber based ones. The fabric homocomposite with 60% fabric prepared by impregnation technique (AH60-I) was superior to the one by stacking technique. The tensile strength of AH60-I was as high as 3.5 times that of the unfilled PTFE. The friction coefficient and wear rate of AH60-I decreased 30% and 77%, respectively. The reinforcing and wear mechanisms were discussed based on the test results and the observations of tensile failure surfaces, wear debris and worn surfaces.