Application of a continuum constitutive model to metallic foam DEN-specimens in compression

The behavior of double-edge notched specimens of metallic foams in compress ion is studied numerically. To model the constitutive behavior of the metal lic foam, a recently developed phenomenological, pressure-sensitive yield s urface [1] is used. Compressive yielding in response to hydrostatic stress is incorporated through a dependence on the plastic Poisson ratio v(p). Res ults are presented in terms of limit load F-lim, as a function of notch dep th, a/W, and the plastic Poisson ratio v(p). For incompressible plastic beh avior, v(p) = 0.5, the results show notch-strengthening due to constrained plastic deformation near the crack/notch-tip. For fully compressible plasti c behavior (no lateral expansion on uniaxial compression, v(p) = 0), no not ch-effect is observed. The validity of using a continuum model for the anal ysis of metallic foam notched specimens is discussed. (C) 2001 Elsevier Sci ence Ltd. All rights reserved.