Investigation on fracture toughness of polytetrafluoroethylene with impact essential work of fracture method

Abstract

Polytetrafluoroethylene (PTFE) polymer has a wide range of applications in various industries. Therefore, for designers it is essential to know the strength properties of the material under dynamic loads. In this study, pure-PTFE, bronze and carbon filled-PTFE are tested under dynamic load. In addition, pure and carbon filled specimens were used to determine the temperature effect of PTFE. All tests were carried out in the Charpy impact device according to impact essential work of fracture method. At 23 degrees C, pure-PTFE showed the highest impact strengths, bronze filled-PTFE and carbon filled-PTFE showed lower respectively and it has been found that the carbon filler increases the fracture toughness approximately two times at high temperature (I 50 degrees C). On fracture surfaces phase transitions effects of PTFE and behavior of fillers used were investigated with Scanning Electron Microscope.