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形状记忆合金(SMA)材料凭借其弹性模量大幅度温变特性被成功应用于智能梁结构变刚度振动控制。根据变刚度控制原理,制定合理的控制策略,成功降低了系统的稳态和瞬态振动响应。试验发现:所采用的Ti50Ni41Cu9三元记忆合金具有较高的热响应速率,在温度控制下相变前后弹性模量能够发生4倍以上变化;将记忆合金板安装于组合梁根部,能够显著调节结构的前3阶固有频率;通过对记忆合金进行变温操作,有效降低了系统共振状态的响应,并研究了变刚度速率对系统非线性特征和控制效果的影响;通过制定温度加载策略,成功实现了宽频段变频激励下智能梁瞬态振动响应的控制。研究结果表明,对记忆合金进行温度控制可以有效改变结构的固有频率并影响振动特性,跨越共振区时进行变刚度操作所导致的非线性特征能够有效分散主频振动能量,较快的刚度变化速率有助于振动响应的进一步降低。
Shape memory alloy (SMA) materials have been successfully applied in the control of variable stiffness and vibration of intelligent beam structures because of their large elastic modulus temperature-dependent properties. According to the principle of variable stiffness control, a reasonable control strategy is formulated to successfully reduce the steady-state and transient vibration response of the system. It is found that the Ti50Ni41Cu9 ternary memory alloy has a high thermal response rate, and the elastic modulus can change more than 4 times before and after the phase change under temperature control. The memory alloy plate can be installed in the root of the composite beam to significantly adjust the structure The first 3 orders of natural frequencies are obtained. By changing the temperature of the memory alloy, the response of the system resonance state is effectively reduced and the influence of the variable stiffness rate on the nonlinear characteristics and control effect of the system is studied. By setting the temperature loading strategy, Control of Transient Vibration Response of Intelligent Beam with Broad Band Frequency Inverted Excitation. The results show that the temperature control of the memory alloy can effectively change the natural frequency of the structure and affect the vibration characteristics. The nonlinear characteristics caused by the variable stiffness operation across the resonance zone can effectively disperse the dominant frequency vibration energy, and the faster the rate of change of the stiffness Helps to further reduce the vibration response.