X状Z向碳pin增强泡沫夹层结构剪切刚度预报

SHEAR STIFFNESS PREDICTION OF X-SHAPE Z-PINNED SAND WICH STRUCTURES

综合考虑了面板对横向增强Z-pin的不同约束情况,结合空间网架结构和等效夹杂方法,提出了X状Z-pins增强泡沫夹层结构剪切刚度的预报模型,经实际计算后与已有的实验值和有限元模拟值比较,证明该方法具有足够的工程精度.计算表明,X状Z-pins能大幅度地提高泡沫夹层结构的剪切刚度,并具有良好的可设计性,可以通过改变Z-pin材料,Z-pin的体积分数、角度、直径等参数改变其力学性能.其中,Z-pin体积分数越大、拉伸模量越高、直径越大,Z-pins增强泡沫夹层结构的剪切刚度越高.

X-shape Z-pin reinforced sandwich is a novel structural core material. It is produced by reinforcing lightweight foam with a truss network of pultruded carbon fiber rods and then laminated between composite facesheets. It has pretty foreground used in aerospace. Under concept of space truss frame and equivalent inclusion method, the paper establishes the method for predicting shear modulus of these composites. The theoretical prediction agrees well with the experimental data and FEM results. The novel Z-pinned cores are found to exhibit favorable programmable properties and higher specific shear stiffness than the of conventional sandwich cores. Altering the volume fraction, pinned angle, diameter and pin materials can effectively ameliorate the mechanical properties of structures. Shear stiffness increases with pin volume fraction,tensile modulus and pin diameter.