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为探明双稳态复合材料层合结构在复杂环境条件下的应用,对双稳态复合材料层合结构的黏弹性行为进行了研究。首先,将纤维简化为弹性材料,考虑基底材料的黏弹性行为。然后,根据纤维和基底的材料属性,通过理论分析得到了双稳态复合材料层合结构的黏弹性材料属性;根据经典层合板理论、最小应变能原理和Maxwell黏弹性模型建立了双稳态复合材料层合结构的黏弹性模型,通过理论分析得到其第二稳态主曲率与扭曲率随加载时间和温度的变化关系。同时,利用有限元软件ABAQUS及其子程序UMAT建立了相应的有限元模型,研究了加载时间和温度对层合结构第二稳态性能的影响。理论与模拟结果均表明:层合结构第二稳态主曲率随加载时间的延长和温度的升高而增大;扭曲率随加载时间的延长而减小,一般情况下随温度的升高而增大,但在加载时间较长且温度较高时,可能会出现扭曲率随温度升高而减小的情况。理论计算结果与有限元模拟结果的比较显示两者吻合较好,可以通过有限元模拟对双稳态复合材料层合结构的黏弹性行为进行研究。
In order to find out the application of bistable composite laminates in complex environment, the viscoelastic behavior of bi-stable composite laminates was studied. First, the fiber is reduced to elastic material, considering the viscoelastic behavior of the base material. Then, according to the material properties of the fiber and the substrate, the viscoelastic material properties of the bistable composite laminated structure are obtained through theoretical analysis. Based on the classical laminate theory, the principle of minimum strain energy and the Maxwell viscoelastic model, the bistable composite The viscoelastic model of the material laminated structure is obtained by theoretical analysis. The relationship between the main curvature and the twist rate of the second steady state with the loading time and temperature is obtained. At the same time, the corresponding finite element model was established by finite element software ABAQUS and its subroutine UMAT, and the influence of loading time and temperature on the second steady-state performance of the laminated structure was studied. The theoretical and simulation results show that the second steady principal curvature of the laminated structure increases with the increase of the loading time and temperature, and the twist rate decreases with the increase of the loading time. Under normal circumstances, with the increase of temperature Increase, but when the loading time is longer and the temperature is higher, the distortion may decrease as the temperature increases. The comparison between theoretical calculation and finite element simulation shows that the two agree well with each other, and the viscoelastic behavior of the bistable composite laminated structure can be studied by finite element simulation.