NiMnGa颗粒/环氧树脂复合材料的力学性能研究

Mechanical properties of NiMnGa particles/epoxy composites

将通过球磨法获得的Ni2MnGa颗粒与双酚A二缩水甘油醚环氧树脂混合均匀并常温固化,制备出相应的复合材料试件;通过拉伸-卸载试验研究了NiMnGa颗粒对树脂基体的增强效果;以试验为基础,从细观力学的角度分析了NiMnGa颗粒对树脂基复合材料弹性特性的影响;采用商用有限元软件Abaqus,对NiMnGa/树脂复合材料单胞模型进行了仿真计算。分析结果表明:随着NiMnGa颗粒体积含量的增加,试件的拉伸模量和剪切模量增大、泊松比减小;随着椭圆NiMnGa颗粒长短半轴比的减小,复合材料纵向泊松比增加、纵向拉伸模量减小,横向拉伸模量呈先减后增的趋势,剪切模量则呈先增后减的趋势。通过对比可知试验值、理论值、有限元模拟值数值相近且变化趋势一致。

Epoxy matrix composites filled with NiMnGa particles are prepared by curing at room temperature.Based on the related loading-unloading experiment of NiMnGa particles/epoxy composites, the effects of NiMnGa particles' volume fraction on resin matrix composite's elastic and damping properties are analyzed via the mesomechanics in detail. Finite element models of unit cells are also established to calculate the composites' elastic properties. It is shown that along with the increasing of Ni-Mn-Ga volume fraction, the composite's tensile modulus and shear modulus increase and the Poisson ratio decreases. As the decreasing of particle major/minor axis ratio, the composite's longitudinal Poisson ratio increases, the longitudinal tensile modulus decreases, the transverse tensile modulus decreases to a valley value and then increases, and the shear modulus increases to a peak value and then decreases. The results of theoretical calculation, finite element simulation and experiments are in good agreement.