Parametric response of a metallic column at elevated temperature

The parametric response of a metallic column at elevated temperature is investigated, taking into account its non-linear viscous characteristics. An asymptotic method for the determination of the region of self-excitation and the amplitudes and phase angles for both stationary and non-stationary responses is outlined briefly. This method is applied to predict the parametric response of a 2618-T61 Al alloy column at 200°C. It is shown that the region of selfexcitation shifts away from the elastic frequency axis, that the amplitude of the stationary response increases sharply as the excitation parameters move from the stability region into the selfexcitation region and that the amplitude of the non-stationary response can be approximated by the stationary response solution for slow varying excitation frequency.