ON THE CRUSHING OF OPEN-CELL FOAMS

Part I: Abstract - Kyriakides

Synthetic cellular materials such as open-cell foams have a complex microstructure consisting of an interconnected network of cells resulting from the foaming process through which they are usually made. The cells are irregular polyhedra with anywhere from 11 to 17 faces. The material is concentrated in the nearly straight edges of the polyhedra and at the nodes where they intersect, usually four at a time. This lecture is concerned with the understanding and modeling of the quasi-static compressive response of open cell polymeric and metal foams. For both classes of materials, the response starts with a nearly linear elastic regime that terminates into a limit load followed by an extensive load plateau. Results from polyester urethane and Al-6061-T6 open cell foams with relative densities of about 0.02 and 0.08 respectively are used to illustrate this behavior using experiments coupled with several levels of modeling. The experiments include characterization of the microstructure using micro-computed X-ray tomography, measurement of the properties of the base material, and measurement of the compressive response of foams of various cell sizes. A sequence of models for predicting the complete response of such foams has been developed.

Part II: Abstract - Reid

A brief account of work on the dynamic (impact or blast generated) crushing of foams, particularly aluminium-based foam (Duocel®) similar to that discussed in Part I, will be presented.  This will include application of the first-order 'shock theory' by Tan, Reid, Harrigan, Zou and Li (JMPS, 53, Parts I and II, 2174-223, 2005) applied to Duocel®.  If time, recently published work (IJIE, 36, 165, 2009) using ABAQUS to model 2D cellular arrays will also be discussed

Speaker

Prof Stelios Kyriakides & Prof S.R. Reid

Venue

Fraser Noble G013