Advanced Mechanical Properties And Deformation Mechanisms Of Bulk Nanostructured Materials

Special topic volume with invited peer reviewed papers only

Bulk nanostructured (NS) materials have emerged as a new class of materials having unusual structures and properties. As a result, they have attracted considerable attention in recent years. Bulk NS materials are single or multi-phase polycrystals with a nanoscale grain size and can usually be classified into nanocrystalline (

The processing and mechanical behaviour of bulk nanostructured materials are one of the most interesting new fields of research on advanced materials systems. Many nanocrystalline materials possess very high strength with still good ductility, and exhibit high values of fatigue resistance and fracture toughness. There has been continuing interest in these nanomaterials for use in structural and biomedical applications, and this has led to a large number of research programs worldwide. This book focuses on the processing techniques, microstructures, mechanical and physical properties, and applications of bulk nanostructured materials, as well as related fundamental issues. Only since recently can such bulk nanostructured materials be produced in large bulk dimensions, which opens the door to their commercial applications.

The investigation of nanocrystalline materials has been an extremely active field during the past two decades as it promises to yield new and exciting properties, which will both test the scientific understanding of the behaviour of materials in general, and offer new scope for applications. While considerable progress has been made in basic understanding, the shift from fundamental science to technological application has been slow, especially with regard to exploitation of the mechanical behaviour of these materials.

Volume is indexed by Thomson Reuters BCI (WoS). Strength and ductility are two of the most important mechanical properties of structural materials, but this usually involves a trade-off, because of the fundamental inverse proportionality of these two features. Since the 1980s, bulk nanostructured materials have emerged as a new class of material having unusual structures and, as a result, have attracted increasing attention. Unfortunately, most bulk nanostructured materials still do not evade the strength-ductility trade-off dilemma, and usually have very poor ductility. The poor ductility of bulk nanostructured materials has indeed become a seemingly insurmountable obstacle to the widespread technological application of structural bulk nanostructured materials.

This book presents a multifunctional approach to the design of bulk nanostructured metals through severe plastic deformation (SPD). Materials engineering has traditionally involved selecting a suitable material for a given application. However, modern engineering frequently requires materials with a set of multifunctional, often conflicting properties: Enhanced mechanical properties need to be combined with improved physical (electrical, magnetic, etc.) and/or chemical (corrosion resistance, biocompatibility) properties. So disparate materials properties need to be engineered and optimized simultaneously. These requirements have created a paradigm shift in which the classical materials selection approach is replaced by design of material microstructures to achieve certain performance requirements, subject to constraints on individual properties such as strength, conductivity, and corrosion resistance. Written by researchers at the forefront of this new materials design approach, the present volume provides a comprehensive introduction to multifunctional design of bulk nanostructured materials, with applications ranging from hydrogen storage to construction engineering.

This book presents the most recent results in the area of bulk nanostructured materials and new trends in their severe plastic deformation (SPD) processing, where these techniques are now emerging from the domain of laboratory-scale research into the commercial production of various bulk nanomaterials. Special emphasis is placed on an analysis of the effect of nanostructures in materials fabricated by SPD on mechanical properties (strength and ductility, fatigue strength and life, superplasticity) and functional behavior (shape memory effects, magnetic and electric properties), as well as the numerous examples of their innovative applications. There is a high innovation potential for industrial applications of bulk nanomaterials for structural use (materials with extreme strength) as well as for functional applications such as nanomagnets, materials for hydrogen storage, thermoelectric materials, superconductors, catalysts, and biomedical implants.

It has been already well established that the nanostructured materials (materials with a grain size of 100mm or less) is the future materials. Nanostructured materials possess properties superior to those of conventional, coarse grained materials. Hence designing potentially cost efficient and environmentally friendly products with better performance is a possibility. Among others, nanostructured materials exhibit increased strength, hardness and ductility and provide an opportunity for superplastic forming. When all the procedures in use for the production of nanostructured materials are examined, only severe plastic deformation (SPD) processes exhibit a potential for producing relatively large samples suitable for industrial applications. In this monograph, the state-of-the-art on severe plastic deformation methods is presented in one volume. The monograph is organised into eight chapters, each of which contains papers on different aspect of severe plastic deformation methods prepared by the experts in this field. The topics covered in the monograph are structure formation, phase transformation, superplasticity, mechanical properties of nanostructured materials, electronic and magnetic properties of nanostructured materials, deformation analysis, novel SPD methods, commercialisation of ECAE method.