DYNAMIC MECHANICAL PROPERTIES OF CROSSLINKED RUBBER

I LINEAR AND NONLINEAR VIBRATION CHARACTERISTICS OF MOUNTING RUBBERS

Abstract

One of the most distinctive characteristics of the vibration of mounting rubbers is a dependence of the dynamic mechanical properties upon the amplitude. For an unloaded polybutadiene, these effects are so small that the experimental response curves agree well with the theoretical curves calculated using a linear equation.
However, nonlinear vibration characteristics of butyl rubber and polybutadiene loaded with carbon black are so pronounced that the linear equation can not be applied.
Thus theoretical response curves were calculated using a nonlinear equation whose nonlinear term was given by (kx-βx³). The results show that the theoretical response curves and free vibration curves obtained from the nonlinear equation for butyl rubber are in good agreement with the experimental results, and the value of β increases with an increasing proportion of carbon black. It was also found for unloaded rubber that tan δ obtained from impact resilience agreed well with tan δ obtained from sinusoidal test.