A rotor shroud for a rotary machine in a cabin air compressor includes a disk portion centered on a central axis of the rotor shroud, a frustoconical portion extending from the disk portion, a flared portion extending from the frustoconical portion, and a variable lattice structure in an interior of the rotor shroud. The variable lattice structure includes a first region of the rotor shroud having a first lattice structure and a second region of the rotor shroud having a second lattice structure. The second lattice structure of the second region is denser than the first lattice structure of the first region. The second region is a deflection region, a stress region, or an energy containment region of the rotor shroud.