AN ANALYTICAL STRESS-STRAIN MODEL FOR OPEN-CELL METAL FOAM

The main objective of the present investigation is to develop an analytical stress-strain model to quantitatively describe the stress-strain behavior of open-cell metal foam. Based on solid mechanics, an analytical stress-strain model is developed. This new stress-strain model involves two main parameters: relative density and plastic Poisson's ratio. As a key characteristic of metal foam, relative density directly takes effect on the uniaxial stress-strain behavior of metal foam and the uniaxial stress of metal foam increases with increasing relative density. Plastic Poisson's ratio is measured as a function of uniaxial compressive plastic strain and its value is neither 0 nor 0.5. Corresponding uniaxial compression tests of metal foams were conducted and numerical simulations were also carried out. The results indicate that this analytical stress-strain model of metal foam is in good agreement with both the experimental validations and the numerical simulations. This work provides useful information for understanding the deformation mechanism of open-cell metal foam.