Pore collapse in powder metal mixtures during shock compression

A multiscale modeling approach is proposed to simulate the mechanical response in porous energetic mixtures during shock loading. A spherically symmetric single pore model is developed that incorporates viscoplastic and temperature dependent effects for a mixture. Our proposed model introduces parameters that capture microstructural effects due to changes in mixture morphology, particle size, and magnitude of the shock load applied to the mixture. These parameters are used to describe geometric, inertial, and constituent interaction effects. The proposed pore collapse model is incorporated into a gas-gun simulation and the parameters are studied with comparisons to experimental results for an intermetallic powder mixture containing Ni+Al.