MECHANICAL PROPERTY CHARACTERIZATION OF A NUMBER OF POLYMERS USING UNIAXIAL COMPRESSION AND SPHERICAL TIPPED INDENTATION TESTS

A number of thermoplastic polymers have been tested in uniaxial compre ssion and by monitoring the force-displacement response of small spher ical indenters loaded into the surface. The compression tests were per formed using a conventional universal testing machine while the very s mall diamond indenters, of nominal 20 and 50 mu m radius, were impress ed only a few micrometres into the surface with a high precision micro mechanical probe. Results from the two approaches are compared and dis cussed in terms of the proposed relationships between hardness or cont act pressure and yield stress for the considered polymers.