THERMOMECHANICAL PROPERTIES OF POLYMERS AT HIGH-RATES OF STRAIN

The dissipation of mechanical energy within a polymer in a relatively short timescale can cause softening of temperature dependant materials and at high strain-rates this effect is more pronounced. Ln the prese nt study, tests have been performed on a bisphenol A epoxy resin, LY-5 64, at strain-rates of approximately 2500s(-1) using a Split Hopkinson Pressure Bar in compression. Temperature measurement has been carried out using a fast response infra-red radiometer developed at Oxford wh ich is able to measure the surface temperature rise of a material duri ng high rate tests. The temperature data shows three distinct slopes. Significant rises in temperature of approximately 50 degrees C have be en recorded during high rate compression tests.