Processing of structural nanocrystalline materials

Abstract

Structural nanomaterials are finding applications in bulk materials, films, coatings, and composites. Applications vary from wear-resistance coatings to load-bearing structures. Nanophase or nanocrystalline materials are also being used in electronics, refractory, biological, and catalytic applications. Progress in a wide range of structural applications for nanomaterials crucially depends on the development of new fabrication and processing technologies, along with a fundamental understanding of the relationship between the structure and properties of the feedstock powders and consolidated parts. Among the most important issues discussed here are experimental data, and theoretical and computer models concerning mechanical properties in nanostructured materials, which, in general, are different from the conventional coarse-grained counterparts. The competition between conventional and unusual deformation modes is believed to cause the unique mechanical properties of nanomaterials, serving as a basis for their structural applications. Fabrication of nanomaterials with bimodal (nano- and sub-micro-particles) composites, that exhibit both very high strength and reasonable ductility, represents a promising strategy in the synthesis of nanomaterials with enhanced properties for various structural applications. High strain rate and low-temperature superplasticity of some nanocrystalline materials are the subjects of growing fundamental research efforts motivated by a range of new applications of these super strong and super plastic materials in net shaping technologies.