The mechanical behaviour of interpenetrating phase composites — III: resin-impregnated porous stainless steel

Powder metallurgy (P/M) derived porous metals that have been impregnated with a polymer resin to create fully dense composites are examples of interpenetrating phase composites (IPCs), in which each phase forms a completely interconnected network. In this paper, we describe an experimental and modelling investigation of the mechanical properties of resin-impregnated P/M derived porous 316L stainless steel composites of various volume fractions, with a view to gaining a better understanding of the mechanical properties of IPCs. In comparison with a similar investigation of 420 stainless/bronze IPCs, properties of the 316L stainless/resin IPCs are less well represented by non-linear finite element analysis based on a unit cell model with periodic boundary conditions. This is attributed to the more irregular microstructure of the 316L/resin IPCs, greater uncertainty in the properties of the constituent materials, and larger differences between constituent properties. Considering only mechanical properties, the 316L stainless/resin combination does not appear to take advantage of the interpenetrating phase morphology, since the resin does not possess a superior property to contribute to the composite as a whole.