Interpenetrating Al O /Al composites were created by liquid metal infiltration of alumina structures with three-dimensional periodicity produced by a robotic deposition method. Volume-averaged lattice strains in the alumina phase were measured by synchrotron X-ray diffraction at various uniaxial compression stresses up to 200 MPa. Load transfer was observed to occur from the aluminum to the alumina phase, and the average state of stress in the alumina is close to uniaxial compression. No change in load transfer was observed upon unloading from 200 MPa, indicating that damage (by alumina fracture or interface decohesion) was absent. 2 3