Abstract
Phase decomposition and ordering reactions in /B2-phase containing TiAl alloys were utilized to establish a novel, previously unreported, type of laminate microstructure. The characteristic constituent of this microstructure are laths with a nanometer-scale substructure that are comprised of several stable and metastable phases. Microstructural control can be achieved by conventional thermomechanical processing and leads to a structurally and chemically very homogeneous material with excellent mechanical properties. The physical metallurgy of this novel type of alloy has been assessed by transmission electron microscope investigations and mechanical testing.