【摘要】 高纯铝箔在特定的溶液下经过电化学阳极氧化腐蚀,可在其表面生成一层多孔的非晶氧化铝层,其孔径分布非常均匀,孔大致呈六方密排布。由于此类薄膜具有规则的纳米级孔径,大的比表面积,良好的自组织排列性,所以其日益受到人们的关注。然而,到目前为止,对于此类薄膜力学性能的研究还很少,所以在一定程度上限制其功能的开发和应用。为了获得此类多孔膜的弹性常数,本文首先由实验出发,通过光力学检测(双光束散斑干涉)的方法得到薄膜拉伸时的整体表观弹性模量。然后对薄膜建立二维有限元模型,运用均匀化理论反推出其基体(无孔结构)的弹性模量,同时考察了不同的基体泊松比对模型整体表观模量的影响,并且用一般有限元方法验证了沿特定方向拉伸时均匀化模型计算的有效性。更多还原

【Abstract】 Amorphous nanoporous alumina films containing parallel capillary pores were fabricated by anodic oxidizing high purity aluminum foils in appropriate acid solutions.The pore diameter distribution is in a small range and the pores are packed in hexagonal dense array.This unique structure has sparked considerable interests due to the large specific surface area and self-ordering.But the research on its mechanical property has scarcely reported,which limits its usage.In this article,uniaxial tensile tests with Electronic Speckle Pattern Interferometry(ESPI) were performed to obtain in-plane Young′s modulus of alumina film.Then assuming alumina matrix(part without pores) is isotropic,together with the theory of homogenization,the relationship between elastic properties of alumina matrix and those of alumina films is deduced,then the elastic modulus of alumina matrix is obtained.The influence of different Passion ratio values on the apparent elastic modulus is also examined,and the validity of this homogenization model in uniaxial tension is approved by the finite element method.更多还原