Microstructurally-based analysis and computational modeling of shock consolidation

The most important microstructural processes involved in shock consolidation are identified and illustrated for a nickel-based superalloy and silicon carbide. Interparticle melting, vorticity, voids, and particle fracture are observed. Various energy dissipation processes are identified and analyzed: plastic deformation, interparticle friction, microkmetic energy, defect generation. An analytical expression is proposed for the energy requirement to shock consolidate a powder as a function of strength, size, porosity, and temperature, based on a prescribed interparticle melting layer. These analytical results are compared to numerical solutions obtained by modeling the compaction of a discrete set of particles with an Eulerian finite element program. Based on the Analysis and computations, the inherent limitations of shock consolidation are identified and discussed.