Thermal behavior of polytetrafluoroethylene in the sintering process

In this study, a thermal model of sintering Polytetrafluoroethylene (PTFE) billet was established. Temperature, which determines the success of the sintering process, was predicted and validated by experiments with less than a 2% error rate. The maximum tensile stress could be increased from 27.9 to 31.6 MPa, and average elongation was also enhanced from 444.12% to 525.27% under controlled crystallization temperature; besides, the tensile stress on the specimen was uniform. Effects of height and diameter ratio on gradient temperature, which reflect on residual stress, were considered, and control temperature and holding time for crystallization were also analyzed. The results reveal that the thermal model can be used for quickly determining appropriate parameters for the sintering process.