MEASUREMENT AND EVALUATION OF DAMPING PROPERTIES OF DAMPING MATERIAL
Chenguang Cai, Qiao Sun
Abstract:
This paper presents a testing method and process of damping properties of a kind of damping material. A damping system was regarded as the experimental subject composed of an oblate solid cylinder specimen of the damping material and an additional mass. The specimen is excited by an electromagnetic shaker in the vertical direction, and the specimen excites the additional mass vibrating. Not only the traditional damping properties, such as the damping ratio and vibration transfer rate, but also the nonlinear properties are measured to evaluate the damping specimen. Firstly the magnitude-frequency characteristics of vibration transfer rate are measured under constant stable excitation over a frequency range of 10 Hz to 320 Hz which includes the resonant frequency of the fundamental mode. Based on the magnitude-frequency characteristic, the half band power method is used to measure the damping ratio. In order to investigate the effects of vibration magnitude on the damping properties, the characteristic of the vibration transfer rate versus excitation magnitude at 210 Hz is measured. The experiment results reveal the fact that linear and nonlinear damping properties of the damping system change as the exciting magnitude increases.
