COLD UNIAXIAL PRESSING OF COMOSITE MATERIALS BASED ON PTFE WITH FUNCTIONAL ADDITIVES TIC AND TIB2

In the current work a solid-phase technology of composite materials based on polytetrafluoroethylene (PTFE) with functional additives is investigated. The mentioned additives are titanium carbides and diborides was obtained by self-propagating high-temperature synthesis (SHS). The process of pressing bulk density composite powders into compact blanks in a special mold by loading in a constant speed mode has been studied. Rheological strainstress curves were obtained. The time when a progressive increasing of stress inside the sample was determined. The results of these studies were compared with data for samples without additives (pure PTFE), as well as for compositions with basalt fiber. It is shown that at stresses 171-177 MPa it is possible to achieve a density corresponding to the calculated compact density of 2.24-2.25 g/cm3. The dependence of density variation over the volume of compact specimens has been studied, and a comparative analysis of the compressibility moduli G under uniaxial cold pressing has been carried out.