Researches on compressive mechanical property of thin-walled hollow spheres structure

The compressive mechanical property of thin-walled hollow spheres structure is researched by experiment and finite element method in this paper. Due to the ideal elastic-plastic material and extremely thin but uniform wall thickness, Ping-Pong balls are bonded together with a linking neck to comprise the ideal model of thin-walled hollow spheres structure. The experimental result validates the effectiveness of the finite element model. The effects of the material and geometry parameters of the spheres and linking neck are then investigated by finite element method. The results reveal that: 1) The deformation process of the two-ball bonding structure includes four stages: elastic deformation, axisymmetric buckling, forming non-axisymmetric polygon and transforming to axisymmetric mode (or structural self-contact behavior); 2) the Young's modulus and initial yield stress are basically unaffected by the linking neck center thickness, but they increase linearly with the hollow sphere wall thickness and linking neck radius as well as the Young's modulus and yield stress of material, and the linear correlation of the material yield stress is the lowest; 3) the strain of structural self-contact behavior increases with the linking neck center thickness and radius.