硅泡沫垫层在振动环境下的温升效应试验研究

Experimental study on temperature rise effect of silicon foam cushion under vibration environment

针对硅泡沫垫层缓冲结构在不同振动量级下体现出不同缓冲传递特性的现象,开展了振动环境下垫层温升及材料非线性与缓冲结构力学特性变化的试验研究。首先通过基础材料试验,建立了垫层材料力学性能随温度变化的关系,再进一步设计了典型硅泡沫垫层缓冲结构,通过设置薄膜温度传感器、电涡流传感器及加速度传感器同时监测试验过程中垫层温度、形变量及结构的力学传递特性变化情况。不同量级下的随机振动试验研究表明,垫层温升与垫层变形幅值呈线性变化关系,振动量级越大,垫层温升越大,缓冲结构的一阶共振频率也越低。在不同振动量级下,垫层温升是导致缓冲结构力学特性变化的因素之一,材料非线性也是影响结构力学特性变化的重要因素。本文研究结果表明在含硅泡沫垫层结构的缓冲设计中,应考虑由于缓冲材料温升效应及材料非线性带来的较高振动量级下缓冲结构力学特性显著变化的问题。

Aiming at the phenomenon that the cushioning structure of silicon foam cushion exhibits different mechanical transfer characteristics under different vibration levels, the relationship between the temperature rise and material nonlinearity of cushioning and the change of the mechanical properties of cushioning structure under vibration environment was studied. The change of the mechanical properties of the cushion material with temperature was obtained through the basic material test, and the typical silicon foam cushion structure was further designed. A temperature sensor was set to get the temperature rise of the cushion, an eddy current sensor was set to monitor the deformation of the cushion, and an acceleration sensor was set to monitor the cushion Changes in the transfer characteristics of structural mechanics, random vibration experiments at different magnitudes were carried out. The research shows that the temperature rise of the cushion layer has a linear relationship with the deformation amplitude of the cushion layer. Under different vibration levels, the temperature rise of the cushion is just one of the factors that lead to the change of the mechanical properties of the damping structure, while the material nonlinearity is the main factor affecting the change of the mechanical properties of the structure. It is reminded that in the structural damping design, the significant change of the mechanical properties of the damping structure at higher vibration levels due to the temperature rise effect of the damping material and the nonlinearity of the material should be considered.