聚乳酸夹层圆筒结构吸能特性实验与分析

Experiment and Analysis for Energy Absorption Characteristics of Polylactic Acid Sandwich Cylinder Structures

基于不同夹层薄壁圆筒结构吸能特性讨论的需要,构造折线、圆弧、正弦、摆线4种夹层形式,以夹层形状、夹层厚度及内外圆筒壁厚为影响因素制订正交试验。采用熔融沉积方法制作聚乳酸试件,在万能试验机上进行轴向压缩实验。由应力应变曲线分析可知,圆弧夹层圆筒结构在弹塑性阶段的应变能密度较高;而综合弹塑性和屈曲阶段,折线夹层为最佳,1.6 mm的夹层厚度和内外圆筒壁厚构成其最佳参数组合,与无夹层圆筒相比,应变能密度可提高37%。

Discussion on energy absorption characteristics of thin-walled cylinder structures with different interlayers, four sandwich forms of polyline, arc, sine and cycloid were constructed. Orthogonal test scheme was formulated by taking the sandwich shapes and their thicknesses, and the thicknesses of inner and outer cylinders as influencing factors. Polylactic acid experimental samples were produced by fused deposition modeling, and then axial compression experiments were carried out on universal testing machine. According to the stress-strain curve analysis, the strain energy density of arc-sandwich cylinder structure was higher in elastic-plastic deformation stage. However, based on the strain energy density in elastic-plastic-buckling deformation stage, the polyline was the best sandwich form, 1.6 mm sandwich thickness and wall thickness of inner and outer cylinders constituted the best parameter combination. Compared with non-sandwich cylinder structure, the strain energy density can be increased by 37%.