This publication presents the proceedings of the International Symposium towards Innovation in Superplasticity. The research project, "Innovation in Superplasticity", was chosen to be one of the priority scientific research efforts in 1996, of the Ministry of Education, Science and Culture, Japan.

The papers of this second conference summarize the progress made in three major target areas; (1) to identify new phenomena in superplasticity, (2) to extend superplasticity research into the atomistic level of grain boundary analysis and (3) to find ways of enhancing collaboration between scientists and industrial engineers.

Superplasticity is the ability of polycrystalline materials under certain conditions to exhibit extreme tensile elongation in a nearly homogeneous/isotropic manner. Historically, this phenomenon was discovered and systematically studied by metallurgists and physicists. They, along with practising engineers, used materials in the superplastic state for materials forming applications. Metallurgists concluded that they had the necessary information on superplasticity and so theoretical studies focussed mostly on understanding the physical and metallurgi cal properties of superplastic materials. Practical applications, in contrast, were led by empirical approaches, rules of thumb and creative design. It has become clear that mathematical models of superplastic deformation as well as analyses for metal working processes that exploit the superplastic state are not adequate. A systematic approach based on the methods of mechanics of solids is likely to prove useful in improving the situation. The present book aims at the following. 1. Outline briefly the techniques of mechanics of solids, particularly as it applies to strain rate sensitive materials. 2. Assess the present level of investigations on the mechanical behaviour of superplastics. 3. Formulate the main issues and challenges in mechanics ofsuperplasticity. 4. Analyse the mathematical models/constitutive equations for superplastic flow from the viewpoint of mechanics. 5. Review the models of superplastic metal working processes. 6. Indicate with examples new results that may be obtained using the methods of mechanics of solids.

This book combines the perspectives of materials science of Superplasticity, on the one hand, and those of design and mechanics, on the other, in order to provide a holistic view of materials, design, mechanics and performance which will lead to useful solutions of societal benefits, in addition to providing great intellectual challenges. After considering the experimental evidence for superplasticity in different classes of materials, the book discusses the physics-based models, along with their advantages and limitations. Then, the analyses for superplastic forming available in the framework of continuum mechanics, finite element analysis and numerical simulations are presented. Finally, the authors highlight some successful industrial applications. This book is recommended as a text book for courses on Superplasticity and as supplementary use for courses on Materials Processing, Manufacturing, High Temperature Deformation, Nanotechnology and Mechanical Behavior of Materials. Persons working in Department of Materials Science and Engineering, Physics, Mechanics, Mechanical Engineering, Aerospace Engineering, Metallurgy, Ceramics and Geo-sciences are likely to find the book to be useful. It is also recommended as a reference source for practicing engineers involved in the design, processing and manufacture of industrial components, which exploit the unique properties associated with superplastic materials.

The book presents practical and theoretical works on superplasticity in metals and ceramics, on deformation mechanisms, on processes to obtain large ultrafine-grained structures, on advanced characterization techniques, and on hot deformation of advanced materials. Key papers focus on (1) processing of metallic alloys for achieving exceptional superplastic properties, (2) high-pressure sliding (HPS) processes, (3) in-situ neutron and synchrotron methods, and (4) ultra-severe plastic deformation. Keywords: Superplasticity, Superfunctionality, High-pressure Sliding, High-pressure Torsion, Precise Forming, Numerical Simulation, Aeronautical Parts, Near-unconstrained Superplastic Parts, Low-temperature Superplasticity, Friction Stir Processing, Microstructure Evolution, Corrosion Properties, Duplex Stainless Steel, Grain Boundary Sliding, Laminated Materials, Asymmetric Hot Rolling, Uniaxial Hot Pressing, Diffusion Bonding.

This book describes the fundamentals and potential applications of 'friction stir superplasticity for unitized structures'. Conventional superplastic forming of sheets is limited to the thickness of 3 mm because the fine grained starting material is produced by rolling. Friction stir superplasticity has grown rapidly in the last decade because of the effectiveness of microstructural refinement. The thickness of the material remains almost constant, and that allows for forming of thick sheets/plates, which was not possible before. The field has reached a point where designers have opportunities to expand the extent of unitized structures, which are structures in which the traditional primary part and any supporting structures are fabricated as a single unit. With advanced optimization and material considerations, this class of structures can be lighter weight and more efficient, making them less costly, as well as mechanically less complex, reducing areas of possible failure. - Discusses how friction stir processing allows selective microstructural refinement without thickness change - Demonstrates how higher thickness sheets and plates can be superplastically formed - Examples are presented for aluminum, magnesium and titanium alloys - Covers the production of low-cost unitized structures by selectively processing cast sheets/plates

This book provides a comprehensive illustration to the superplastic forming/diffusion bonding (SPF/DB) technology developed over decades of research on titanium alloys, process modeling, and its application. SPF/DB technology plays key roles in building aviation components with complicated structures, with highly beneficial effects when well designed. With the ever-increasing demand on components with multiple layers, there is an urgent need for an updated assessment of traditional and modern SPF/DB processing methods. Success critically depends on making the most practical and effective choice of SPF/DB method for a given application. The book introduces titanium and titanium alloys, SPF/DB processing and its modeling, and applications for building typical single or multiple layer(s) structures. Particular attention is paid to illustrating the microstructure evolution during SPF/DB processes. The information for making technical decisions about optimal choice of measurement and evaluation methods is also given in the book. Each chapter follows a focused and pragmatic format. Fully illustrated throughout, the book presents the state of the art in SPF/DB technology in a manner that makes it useful for engineers to improve the established forming processes and quality of components. This book is an essential reading material for industrial practitioners, academic researchers and postgraduates.