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自行设计了一种测量材料阻尼性能的方法——悬臂梁法。用该法测量了所合成的PU/EP IPN材料在钢片上的约束层及自由层阻尼(dB—频率谱)。结果表明:PU/EP IPN的振动阻尼性能大大优于纯PU,它不仅阻尼频域(或温域)宽,而且可以改变系统的自振频率(向低频移动约100HZ)。在以PU/EP(70/30)IPN为粘弹阻尼层,以PVC为约束层时,阻尼效果最佳。当IPN粘弹层/PVC约束层/钢片的厚度比为3.5/3.5/4.0时,振动信号在0—20 KH_2的频域内平均可衰减约20d B(A)。
A method of measuring the damping property of materials - cantilever beam method was designed by myself. Using this method, the constrained layer and free layer damping (dB-frequency spectrum) of the synthesized PU / EP IPN material on the steel sheet were measured. The results show that the vibration damping performance of PU / EP IPN is much better than that of pure PU. It not only widens the frequency domain (or temperature range) but also changes the system natural frequency (about 100HZ to low frequency). In the PU / EP (70/30) IPN viscoelastic damping layer, with PVC as the constraining layer, the damping effect of the best. When the thickness ratio of IPN viscoelastic layer / PVC constraining layer / steel sheet is 3.5 / 3.5 / 4.0, the vibration signal attenuates about 20d B (A) on average in the frequency range of 0-20 KH_2.