论文部分内容阅读
基于一种新颖的建模方法——变分渐近均匀化理论,建立了磁致伸缩复合材料的细观力学模型,以准确预测材料的有效属性和局部应力、磁通密度分布。从建立磁致伸缩复合材料的总磁焓入手,将总磁焓中的场变量精确解表示为平均值和波动函数之和。根据最小势能原理,利用细宏观尺度比作为小参数对约束条件下总磁焓求驻值(最小化)建立细观力学模型。为分析实际工程中的微观结构,利用有限元离散技术实现构建模型的数值模拟。CoFe_2O_4/环氧树脂复合材料数值算例结果表明:构建的模型可准确预测磁致伸缩复合材料的有效属性和局部场分布,并可扩展到其他多相复合材料的有效属性和局部场分析中。
Based on a novel modeling method-variational asymptotic homogenization theory, a mesomechanical model of magnetostrictive composite was established to accurately predict the material’s effective properties and the local stress and magnetic flux density distribution. Starting from the total enthalpy of the magnetostrictive composite, the field variables in the total enthalpy of solution are accurately expressed as the sum of the mean and the fluctuation function. According to the principle of minimum potential energy, a mesomechanical model was established by using the fine macro-scale ratio as the small parameter to find the value of the total enthalpy (minimization) under the constraint conditions. In order to analyze the microstructure in practical engineering, the finite element discretization technique is used to realize the numerical simulation of the building model. The numerical results of CoFe_2O_4 / epoxy composites show that the model can accurately predict the effective properties and local field distribution of magnetostrictive composites, and can be extended to the effective properties and local field analysis of other multiphase composites.