Effect of ceramic preform geometry on load partitioning in Al₂O₃-Al composites with three-dimensional periodic architecture

Interpenetrating Al₂O₃/Al composites were created by liquid-metal infiltration of 3D periodic ceramic preforms with face-centered-tetragonal symmetry produced by direct-write assembly. Volume-averaged lattice strains in the ceramic phase of the composite were measured by synchrotron X-ray diffraction for various levels of uniaxial compression stresses. Load transfer is found to occur from the metal phase to the ceramic phase, and the magnitude of the effect is in general agreement with simple rule-of-mixtures models. Spatially resolved diffraction measurements show variations in load transfer at two different positions within the composite for the elastic- and damage-deformation regimes, the latter being observed using phase-enhanced synchrotron imaging. The mechanical behavior of these interpenetrating Al₂O₃/Al composites with face-centered-tetragonal symmetry are compared with previous interpenetrating Al₂O₃/Al composites with simple-tetragonal symmetry.