Engineering Of Metallic Interpenetrating Phase Composites For The Control Of Deformation And Failure Modes During Dynamic Events

Aerospace components, automotive structures, and ballistics armor are all engineered to withstand high strain rate service events through a combination of material selection and design choices. However, structural components may be less effective when their implementation is constrained by other factors such as weight or design limitations. To meet these challenges, the development of next-generation materials will need to increasingly rely on composite material systems rather than monolithic materials. This thesis presents the fabrication, dynamic characterization testing, and post-mortem analysis of 316L/A356 interpenetrating phase composites (IPCs) made from the PrintCasting methodology. These composites consist of additively manufactured 316L stainless steel lattices as a reinforcement phase and infiltrated as-cast A356 aluminum for a matrix phase. Two reinforcement lattice geometries, the gyroid and simple cubic, were evaluated at volume fractions of 1/3 and 2/3 stainless steel. Dynamic behavior of the composites was performed using a Split-Hopkinson Pressure Bar (Kolsky bar) system to assess mechanical performance. Post-mortem optical and scanning electron microscopy (SEM) were used to characterize the deformation mechanisms of the composites. The results demonstrated that the lattice geometry and volume fractions of phases influence the mechanical behavior and deformation of the composites. This work establishes a framework for the fabrication of 316L/A356 IPCs and provides a foundation for future iterations involving new lattice designs, PrintCasting optimization, alternative material selection.