| Abstract Scope |
We evaluate sources of microstructure-driven variability in the mechanical behavior of porous metals intended for deployment in fusion reactors. Microstructural aspects of interest include properties of the cavities (e.g., spatial arrangement, size distribution, overpressure), matrix properties (e.g., lattice type, lattice orientation, and strain rate sensitivity), and their interaction effects. Results indicate that relatively low to moderate variability is associated with these aspects in well distributed random microstructures. However, significant variability, up to seven-fold relative difference, in the steady state strain-rate was found to be induced by a coupling among ordered cavity arrangements, lattice orientation, porosity, and strain-rate sensitivity. Results indicate that less compliant microstructures are more prone to coalescence whereas more compliant microstructures are more prone to diffuse growth. For random cavity arrangements, this coupling is effectively averaged out but it still influences the local stress fields in the anticipated locations in ways that affect coalescence, nucleation, and fracture. |