The contact mechanics of cellular solids

A model for the contact of a cellular solid with a compact counter-surface is developed. The cell walls and edges at the surface of the cellular solid deform elastically by compression and bending and, at larger forces, colla pse. For open cell materials, a simple general equation is derived relating the fraction f of cell edges in contact to the applied compressive stress sigma. The ratio sigma/f is proportional to an average strain of the cell s truts in contact, which is calculated in particular cases. A geometrical co nstruction is described with which the fraction f can be obtained as a func tion of the applied stress sigma. The analysis of the contact of closed cel l materials is also undertaken, leading to relations between the applied st ress and the fractions of edges and walls in contact. (C) 1999 Elsevier Sci ence S.A. All rights reserved.