On Energy Absorption Mechanism Of Honeycomb Sandwich Structures Under Quasi-static Local Indentation

Aluminum honeycomb structure is a typical porous structure.Because of its high quality,high rigidity,high specific strength and good insulation noise and other outstanding performance come to the fore,in the aerospace,defense.and the automotive industry has been widely used.The honeycomb sandwich panel is a kind of lightweight structure with good bearing energy absorption characteristics,and has wide application prospect in the automobile industry.From a security point of view,the sandwich structure will be due to bird hit,hail,tool drop,car Mercedes,shock wave and car collision caused by high-speed operation of the stone fragments caused by local impact damage.The performance of sandwich structure after impact directly influences the structural integrity and safety.Therefore,it is very important to study the anti-penetration performance of sandwich structure for its better popularization and application in body structure design.In this paper,a series of research work on the anti-penetration performance and local perforation failure mechanism of honeycomb sandwich plates were carried out by means of experimental study and numerical simulation.(1)Conducting quasi-static local penetration experiments of monolayer panels and honeycomb sandwich panels to explore the different geometrical parameters including panel thickness,honeycomb core height,aluminum foil thickness,and hexagonal honeycomb size.The experimental results show that increasing the thickness of the panel,the size of the hexagonal honeycomb and reducing the height of the honeycomb sandwich,reducing the thickness of the aluminum foil can significantly improve the anti-penetration performance and energy absorption characteristics of the honeycomb sandwich board.(2)The finite element model of honeycomb sandwich panel is established,and the validity of the finite element model is verified by comparing the simulation results with the experimental results.Based on the finite element model,the anti-penetration performance of air sandwich board and honeycomb sandwich panel is compared and analyzed,and the excellent performance of honeycomb sandwich panel is highlighted.And the influence of boundary constraint,indenter size and indentation shape on the anti-penetration performance of honeycomb sandwich panel was explored.(3)A kind of bionic hierarchical honeycomb sandwich panel structure is proposed,and the anti-penetration performance of hierarchical honeycomb and traditional honeycomb sandwich panel is analyzed.Based on the structural parameters of multi-stage honeycomb structure,Effect of the boundary constraint,the size of the indenter and the shape of the indenter on the anti-penetration performance of the multi-stage honeycomb sandwich plate were analyzed.The results show that the structural parameters y and the density of the hierarchical honeycomb sandwich have a great influence on the performance of the hierarchical honeycomb sandwich panel.Zero-level honeycomb sandwich panel absorb more energy,but by the damage,failure even greater.The first order honeycomb sandwich panel absorbs less energy than a zero level honeycomb sandwich panel,but the area of damage is less distorted.