The research interests of M. E. McHenry can be broadly categorized as involving the development of an understanding of the magnetic properties of materials. This includes interfacing theoretical and experimental studies of magnetic materials. Superconducting materials are included in this broad realm since the most important technical property of superconductors, their current carrying capacity or critical current density, is a magnetic properties (i.e determined by the ability of these materials to pin magnetic flux). Given his perception of the great potential for application of high temperature superconducting materials his early research work after joining the CMU faculty was in this area.

He subsequently initiated a program to investigate fundamental magnetic properties of magnetic surfaces, interfaces and multilayers. The possibility of tailoring magnetic properties on the atomic level is just now being realized and hold great potential promise for development of novel magnetic materials perhaps even as magnetic storage media of the future. He has a continuing interest in the magnetic properties of icosahedral structures includes the study of magnetic quasicrystals and the magnetic and superconducting properties of fullerenes.

Prof. McHenry most recent efforts have evolved from the study of carbon-coated magnetic nanocrystals produced by the Kratschmer-Huffman carbon arc method and developing a description of fine particle magnetism in the same. This lead to studies of the plasma torch synthesis of metallic, C-coated, oxide, carbide and nitride nanoparticles. Most recently reactive gas plasma torch synthesis has been used to produce nanocrystalline ferrite materials for very high frequency applications. The surface structure, and its influence on properties, is being studied in faceted ferrite nanoparticles.

Prof. McHenry has developed an active program of research in the area of soft magnetic metallic nanocomposites. These nanocomposites have excellent soft magnetic properties as measured by the figures of merit of combined induction and magnetic permeability. Soft magnetic nanocomposite materials are categorized in terms of the nanocrystalline magnetic phase. FINEMET, has Fe-Si nanocrystals possessing an ordered DO₃ structure; NANOPERM (Fe₈₈Zr₇B₄Cu) has a-Fe and the CMU discovery HITPERM has alpha-FeCo nanocrystalline grains all embedded in amorphous magnets. In HITPERM nanocomposites the a (B2)-FeCo is formed with significantly improved high temperature magnetic properties than in NANOPERM and FINEMET. High temperature operation is advantageous for the application environment, to allow integration with other high temperature electronic components, or to increase efficiency by going to higher frequency.