The temperature dependence of yield of polycarbonate in uniaxial compression and tensile tests

The tensile yield stress is compared with the uniaxial compression yield stress for specimens of polycarbonate tested at constant strain rate from -120 to + 120°C. The strain rate dependence of the tensile yield stress is also studied from - 140 to + 20°C. The yield behaviour is described by a modification of the Eyring theory of non-Newtonian viscosity where the deformation is supposed to involve two different flow processes. The validity of a yield criterion previously established by one of us, is checked throughout the range of temperatures explored; the proposed equation gives a good fit to the data provided it is applied separately to each flow process. Then the present investigation, combining the yield condition with the modified Eyring theory, provides a formalism which agrees with the data and accurately renders the temperature, strain rate and pressure dependence of the yield stress of polycarbonate. © 1972 Chapman and Hall Ltd.
SCOPUS: ar.j
info:eu-repo/semantics/published