DEVELOPMENT OF TECHNIQUE FOR DAMPING CAPACITY IMPROVEMENT BY COMPOSITE SURFACE STRUCTURE

机器中的薄板结构在运行过程中经常剧烈振动。本研究开发了一些提高阻尼能力的技术来防止这种振动。它们非常简单，不需要很多钱。首先，介绍了双面胶带在薄板表面涂覆的结构模型的微分方程组。在这里，自由倾倒振动被处理。从该方程组的解出发，证明了粘贴胶带对提高阻尼能力的有效性，并阐明了粘贴胶带的特性。胶带的一个重要特性是抗剪切变形。我们将此特性命名为剪切应变速度系数（SSVC）。在此基础上，测量了实际薄板结构的阻尼特性，并通过实验验证了胶带对薄板结构阻尼特性的改善作用。结合实验和理论结果，可以估计出S…More SVC。这种估计是在模型结构的动态状态下得到的。对SSVC进行了一些直接澄清实验。由于实验装置所实现的剪切应变速度范围很小，只能得到静态的特征值。然而，动态估计和静态估计之间具有良好的线性关系。结果表明，具有较大静态SSVC的胶带能有效提高胶带的阻尼能力。以上结果均为初始反应试验所得。然后，分别对其抗强迫振动的有效性进行了检验。结构与加速点直接接触，作用在加速点上的摩擦力对阻尼能力提高的程度影响较大。说明在受迫振动时，阻尼能力也略有提高。在最后的实验中，检验了化学镀膜对提高阻尼性能的有效性。任何类型的化学镀膜都可以提高阻尼能力。镀膜中分散有SiC等坚硬的外来小颗粒，大大提高了镀层的阻尼能力。少

Sheet structures in machines often vibrate violently during operation. Some techniques for damping capacity improvement to prevent such vibration are developed in this research. They are very simple and do not require much money.Firstly, a differential equation system representing a structure model in which double-sided adhesive tape is applied on sheet surfaces is introduced. Here, a free dumped vibration is treated. From the solution of this equation system, the effectiveness of applied adhesive tape on damping capacity improvement is proved and the characteristic of the applied adhesive tape is clarified. An important characteristic of applied adhesive tape is the resistance against shearing deformation. We named this characteristic as shearing strain velocity coefficient (SSVC).Then, damping characteristic of actual sheet structures is measured and its improvement by adhesive tape application is recognized in experiment. By combining both the experimental and theoretical results, S … More SVC can be estimated. Such estimation is obtained in the dynamic state of the model structure.Some experiments to clarify SSVC directly have been carried out. Only a characteristic value for static state is obtained, because a small shearing strain velocity range is realized in our experimental apparatus. However, good linearity between the dynamic estimation and the static estimation is recognized. It is clarified that an adhesive tape having large static SSVC is effective for large damping capacity improvement.Above results are obtained in indicial response test. Then, the effectiveness against forced vibration is separately examined. Structure directly contacts the accelerating point, and friction force acting on this point has a large influence on the level of damping capacity improvement. It is clarified that damping capacity is slightly improved also in forced vibration.In the last experiment, the effectiveness of electroless plating film on damping capacity improvement is examined. Any types of electroless plating film can improve damping capacity. Damping capacity is greatly improved by the plating film dispersed with hard foreign small particles such as SiC. Less