球形孔洞泡沫铝力学行为的SPH分析

SPH SIMULATION OF MECHANICAL BEHAVIOR OF ALUMINUM FOAM WITH SPHERICAL VOIDS

分别基于体心立方元胞模型和随机孔洞模型建立了泡沫铝SPH模型.采用SPH方法分析了准静态加载条件下泡沫铝的单轴压缩力学性能.最大应变达70%.SPH计算所得应力-应变曲线表现出明显的弹性、平台和压实三段.分析了泡沫铝的微观变形机理,结果表明规则模型和随机模型均呈现出明显的局部塑性变形带,其中随机泡孔模型的孔壁变形以弯曲为主,局部塑性变形带表现更为明显.本文研究结果同时还说明了采用SPH方法研究泡沫材料力学行为的可行性与适应性.

Typical particle models of Aluminum foam with spherical void were built.Voids were distributed with the configuration of body centered cubic(BCC)in the first model,while voids were distributed randomly in the second model.Quasi-static compression simulation of these models based on smooth particle hydrodynamics(SPH)were carried on to analysis their mechanical behaviors.The largest strain applied was 70%.Results showed that stress-strain relationship consists of three regions including a elastic region,aplatform region and a condensation region.Results also revealed localized plastic zones both in BCC and random models.We can draw the conclusion that SPH is applicable to the mechanical simulation of porous media.