Vibrocreep of polymeric materials

Abstract

Experimental data on the static and vibrational creep of rigid porous polyurethane are used in an analysis of the time dependence of the vibrocreep coefficient and its dependence on the derivative of the stresses created by the incremental vibrational load and the static stress level. It is shown that at a constant value of the static stresses and the incremental vibrational load the vibrocreep coefficient decreases with time and in long-time vibrocreep tends to unity. As the parameter characterizing the vibrocreep coefficient for a given moment of time it is possible to employ the amplitude of the dynamic stress rate. The dependence proposed for describing the vibrocreep coefficient curves satisfactorily describes the experimental data. It is shown that the value of the vibrocreep coefficient does not depend on the static stress level (up to 0.5 of the short-time strength).