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Monolithic Nb5Si3 films and microlaminates consisting of alternating, equally thick layers of Nb and Nb5Si3 were synthesized by magnetron sputtering. Thick monolithic Nb5Si3 films (25,000 nm) were deposited on a sapphire substrate to set process parameters and evaluate the microstructure and mechanical properties of as-deposited crystalline films. Nb5Si3/Nb micro-laminates with modulation wavelengths (i.e., bilayer thickness) of 40 and 200 nm were deposited on Nb substrates. Mechanical properties (elastic modulus, microhardness, compressive yield strength) of the films and microlaminates were studied using the nanoindentation method and Vickers microhardness. Mechanical property test results are presented.

The mode of superplastic deformation is an important issue that is under considerable discussion in many the unusual resistance to necking is due to the high strain rate sensitivity of flow stress(10), no general agreement exists at present as to what mechanism is responsible for this effect. The high strain rate sensitivity of flow stress has been attributed to diffusional