SLM Process And Performance Evaluation Of Simple Cubic Negative Poisson's Ratio Material

At present,lightweight structures are generally used to fill the original solid parts in the spacecraft,and the lightening target is achieved in this way.The simple cubic negative Poisson’s ratio material is a kind of lightweight structure with many advantages.Compared with the traditional Zheng Poisong lightweight structure,it has a large energy absorption ratio,good anti-depression ability and fracture resistance.Higher shear strength and other characteristics.Therefore,the simple cubic negative Poisson’s ratio material has broad application prospects in the spacecraft lightweighting process.However,in practice,due to different applications,simple cubic negative Poisson’s ratio materials with different properties are often needed.Therefore,how to artificially control the performance of the structure becomes a difficult point in the design and application of simple cubic negative Poisson’s ratio materials.The side length c of the initial cell,the major axis short axis ratio R of the ellipse,and the half length b of the ellipse are taken as the design parameters of the structure,according to the structure.The relationship between the volume of the hollow part and the volume of the solid part establishes the mathematical expression of the design parameters and the relative density;since the negative Poisson elliptical porous structure and the negative Poisson rotating square structure have the same deformation characteristics,the negative Poisson rotation The square structure can be replaced by two diagonal lines of its square.Therefore,the negative Poisson elliptical porous junction is simplified into a diagonal model,and the design parameters are established according to the deformation characteristics of the diagonal model under force.The theoretical expression between Poisson’s ratio is verified by finite element analysis.the Gibson-Ashby model is used to establish the mathematical model between the negative Poisson elliptical porous design parameters and its Young’s modulus.The constant coefficient of the mathematical model is determined by quasi-static compression test.the mathematical model and structure of the relative design density of the structural design parameters and structure are used.The amount of mathematical expression,the mathematical expression as the structure of the Poisson’s ratio,three objective function based multi-objective optimization particle swarm optimization,to obtain a set of optimal design parameters of the negative Poisson’s elliptical porous structure.