碳纤维增强环氧树脂复合材料金字塔点阵夹芯假脚结构在竖向载荷下的力学性能

Mechanical properties of carbon fiber reinforced epoxy composite pyramid lattice sandwich prosthetic foot structure under vertical load

对碳纤维增强树脂复合材料金字塔点阵夹芯假脚结构在竖向载荷下的力学性能进行研究。制备了三种不同相对密度的假脚,并进行了竖向载荷压缩试验。结果表明,相对密度对结构力学性能的影响显著,载荷-位移曲线呈非线性,峰值载荷和刚度值随相对密度的增加而增大,三种相对密度的破坏模式均为节点的失效和面板的皱曲,结构具有一定的能量吸收能力。建立了金字塔点阵夹芯假脚结构的理论强度预报模型,给出了结构在竖向载荷作用下的挠度响应,获得了四种失效模式和临界破坏载荷。对比了理论计算与试验的峰值载荷、破坏模式和挠度,得到较好的一致性。给出假脚结构参数(面板厚度、杆件角度和杆件直径)对破坏模式和破坏临界载荷的影响,并绘制了结构失效机制图。

The mechanical properties of the carbon fiber reinforced epoxy composite pyramid lattice sandwich prosthetic foot structure under vertical load were studied.Three kinds of prosthetic feet with different relative densities were prepared and subjected to vertical load compression test.The results show that the relative density has a significant effect on the mechanical properties of the structure.The load-displacement curve is nonlinear.The peak load and stiffness values increase with the increase of the relative density.The three failure modes of relative density are node failure and panel wrinkling.Curves and structures have a certain energy absorption capacity.The theoretical strength prediction model of the pyramid lattice sandwich prosthetic foot structure was established,and the deflection response of the structure under the vertical load was given.Four failure modes and critical failure loads were obtained.Comparing the peak load,failure mode and deflection of theoretical calculation and experiment,a good consistency is obtained.The effect of the structural parameters of the prosthetic foot(thickness of the panel,angle of the rod and diameter of the rod)on the failure mode and the critical load of the failure were given,and the structural failure mechanism diagram was drawn.