Elastic constants of lotus-type porous metal : measurement and micromechanics modeling

We studied the elastic property of a lotus-type porous copper using the combination of resonance ultrasound spectroscopy and electromagnetic acoustic resonance methods to determine all the independent elastic constants. We observed the elastic anisotropy. The parallel Young's modulus E_<⫽> decreases linearly with porosity, while the normal E_<⊥> drops rapidly and then slowly. Micromechanics calculations considering the elastic anisotropy of the matrix (textured metal) can reproduce the measured anisotropic elastic constants. This indicates that the elastic properties of the various types of porous metals can be predicted and designed with the present approach using micromechanics modeling.