A Note on the Micromechanics of Plastic Yield of Porous Solids

Experimental evidence suggests that, for materials exhibiting no appreciable work hardening and containing no more than approximately 20% volume fraction of pores, the macroscopic strain at which yield occurs is nearly constant, with a tendency to increase slightly as porosity increases. The present work shows that both observations - approximate constancy of strain at yield and its tendency to increase with porosity - have a relatively simple micromechanical explanation.