Syntactic Iron Foams – On Deformation Mechanisms and Strain‐Rate Dependence of Compressive Properties

Abstract

AbstractSyntactic iron foams are produced by metal injection moulding from pure Fe powder and two grades of commercial glass microspheres. Mechanical performance of samples containing 5/10/13 wt% of microspheres is compared to unfilled reference material properties at strain‐rates covering 6 orders of magnitude, including Split Hopkinson Pressure Bar (SHPB) experiments. Complex mechanical behavior including strengthening effects of microspheres leading to a plateau strength level which is nearly independent of porosity as well as strain‐rate sensitivity of compressive properties are observed. Typical plateau onset stress levels exceed equivalent characteristics of most comparable cellular metallic materials, reaching between approximately 220 and 270 MPa under quasi‐static conditions, depending on amount and type of added microspheres. A qualitative explanation of significant events in the deformation sequence as reflected in the stress–strain‐curve is offered and discussed in the context of existing studies on syntactic foams. A course for further investigations to verify this hypothesis is suggested.