Ion Irradiation Induced Damage and Dynamic Recovery in Single Crystal Silicon Carbide and Strontium Titanate


Book Description

The objective of this thesis work is to gain better understanding of ion-solid interaction in the energy regime where electronic and nuclear energy loss are comparable. Such responses of materials to ion irradiations are of fundamental importance for micro-electronics and nuclear applications. The ion irradiation induced modification for the crystal structure, the physical and chemical properties etc. may strongly affect the performance of functional materials that needs to be better understood. Experimentally, ion irradiation induced damage accumulation and dynamic recovery in SiC [silicon carbide] and SrTiO3 [strontium titanate] were studied in this dissertation project. Five chapters are presented: Firstly, electronic stopping power for heavy ions in light targets was experimentally evaluated for SiC. Secondly, out-surface diffusion of Ag atoms through SiC coating layer was studied by ion implantation and thermal annealing. The result also suggested that a SiO2 [silicon dioxide] thin film might serve as a diffusion barrier. Thirdly, a thermally induced recovery was studied for single crystal SiC. Through well controlled isothermal and isochronal annealing processes, activation energies were estimated and attributed to certain defect migration/recombination mechanisms. The fourth chapter focuses on a competing effect on defect dynamics due to ionization-induced defect recovery in SiC. Recovery of the existing defects resulting from a thermal spike along the ion path was expected, and was experimentally confirmed by using energetic ions. The results suggest a low threshold of electronic stopping power for the ionization-induced recovery. In the last chapter, an example of how the target material responses differently to energy deposition are demonstrated for single crystal SrTiO3. Instead of the recovery that was observed in SiC, a synergy effect of the coupled electronic and nuclear stopping energy deposition leads to formation of amorphous ion tracks. Systematic studies towards the role of defect concentration and electronic stopping power in the synergy effect were performed.







Forward Recoil Spectrometry


Book Description

The practical properties of many materials are dominated by surface and near-surface composition and structure. An understanding of how the surface region affects material properties starts with an understanding of the elemental composition of that region. Since the most common contaminants are light elements (for example, oxygen, nitrogen, carbon, and hydrogen), there is a clear need for an analytic probe that simultaneously and quantitatively records elemental profiles of all light elements. Energy recoil detection using high-energy heavy ions is unique in its ability to provide quantitative profiles of light and medium mass elements. As such this method holds great promise for the study of a variety of problems in a wide range of fields. While energy recoil detection is one of the newest and most promising ion beam analytic techniques, it is also the oldest in terms of when it was first described. Before discussing recent developments in this field, perhaps it is worth reviewing the early days of this century when the first energy recoil detection experiments were reported.




Chemical Abstracts


Book Description




Fundamentals of Radiation Materials Science


Book Description

The revised second edition of this established text offers readers a significantly expanded introduction to the effects of radiation on metals and alloys. It describes the various processes that occur when energetic particles strike a solid, inducing changes to the physical and mechanical properties of the material. Specifically it covers particle interaction with the metals and alloys used in nuclear reactor cores and hence subject to intense radiation fields. It describes the basics of particle-atom interaction for a range of particle types, the amount and spatial extent of the resulting radiation damage, the physical effects of irradiation and the changes in mechanical behavior of irradiated metals and alloys. Updated throughout, some major enhancements for the new edition include improved treatment of low- and intermediate-energy elastic collisions and stopping power, expanded sections on molecular dynamics and kinetic Monte Carlo methodologies describing collision cascade evolution, new treatment of the multi-frequency model of diffusion, numerous examples of RIS in austenitic and ferritic-martensitic alloys, expanded treatment of in-cascade defect clustering, cluster evolution, and cluster mobility, new discussion of void behavior near grain boundaries, a new section on ion beam assisted deposition, and reorganization of hardening, creep and fracture of irradiated materials (Chaps 12-14) to provide a smoother and more integrated transition between the topics. The book also contains two new chapters. Chapter 15 focuses on the fundamentals of corrosion and stress corrosion cracking, covering forms of corrosion, corrosion thermodynamics, corrosion kinetics, polarization theory, passivity, crevice corrosion, and stress corrosion cracking. Chapter 16 extends this treatment and considers the effects of irradiation on corrosion and environmentally assisted corrosion, including the effects of irradiation on water chemistry and the mechanisms of irradiation-induced stress corrosion cracking. The book maintains the previous style, concepts are developed systematically and quantitatively, supported by worked examples, references for further reading and end-of-chapter problem sets. Aimed primarily at students of materials sciences and nuclear engineering, the book will also provide a valuable resource for academic and industrial research professionals. Reviews of the first edition: "...nomenclature, problems and separate bibliography at the end of each chapter allow to the reader to reach a straightforward understanding of the subject, part by part. ... this book is very pleasant to read, well documented and can be seen as a very good introduction to the effects of irradiation on matter, or as a good references compilation for experimented readers." - Pauly Nicolas, Physicalia Magazine, Vol. 30 (1), 2008 “The text provides enough fundamental material to explain the science and theory behind radiation effects in solids, but is also written at a high enough level to be useful for professional scientists. Its organization suits a graduate level materials or nuclear science course... the text was written by a noted expert and active researcher in the field of radiation effects in metals, the selection and organization of the material is excellent... may well become a necessary reference for graduate students and researchers in radiation materials science.” - L.M. Dougherty, 07/11/2008, JOM, the Member Journal of The Minerals, Metals and Materials Society.




Extractive Metallurgy of Niobium


Book Description

The growth and development witnessed today in modern science, engineering, and technology owes a heavy debt to the rare, refractory, and reactive metals group, of which niobium is a member. Extractive Metallurgy of Niobium presents a vivid account of the metal through its comprehensive discussions of properties and applications, resources and resource processing, chemical processing and compound preparation, metal extraction, and refining and consolidation. Typical flow sheets adopted in some leading niobium-producing countries for the beneficiation of various niobium sources are presented, and various chemical processes for producing pure forms of niobium intermediates such as chloride, fluoride, and oxide are discussed. The book also explains how to liberate the metal from its intermediates and describes the physico-chemical principles involved. It is an excellent reference for chemical metallurgists, hydrometallurgists, extraction and process metallurgists, and minerals processors. It is also valuable to a wide variety of scientists, engineers, technologists, and students interested in the topic.




Introduction to Glass Science and Technology


Book Description

This book provides a concise and inexpensive introduction for an undergraduate course in glass science and technology. The level of the book has deliberately been maintained at the introductory level to avoid confusion of the student by inclusion of more advanced material, and is unique in that its text is limited to the amount suitable for a one term course for students in materials science, ceramics or inorganic chemistry. The contents cover the fundamental topics of importance in glass science and technology, including glass formation, crystallization, phase separation and structure of glasses. Additional chapters discuss the most important properties of glasses, including discussion of physical, optical, electrical, chemical and mechanical properties. A final chapter provides an introduction to a number of methods used to form technical glasses, including glass sheet, bottles, insulation fibre, optical fibres and other common commercial products. In addition, the book contains discussion of the effects of phase separation and crystallization on the properties of glasses, which is neglected in other texts. Although intended primarily as a textbook, Introduction to Glass Science and Technology will also be invaluable to the engineer or scientist who desires more knowledge regarding the formation, properties and production of glass.




Field-Assisted Sintering


Book Description

This book represents the first ever scientific monograph including an in-depth analysis of all major field-assisted sintering techniques. Until now, the electromagnetic field-assisted technologies of materials processing were lacking a systematic and generalized description in one fundamental publication; this work promotes the development of generalized concepts and of comparative analyses in this emerging area of materials fabrication. This book describes modern technologies for the powder processing-based fabrication of advanced materials. New approaches for the development of well-tailored and stable structures are thoroughly discussed. Since the potential of traditional thermo-mechanical methods of material treatment is limited due to inadequate control during processing, the book addresses ways to more accurately control the resultant material's structure and properties by an assisting application of electro-magnetic fields. The book describes resistance sintering, high-voltage consolidation, sintering by low-voltage electric pulses (including spark plasma sintering), flash sintering, microwave sintering, induction heating sintering, magnetic pulse compaction and other field-assisted sintering techniques. Includes an in-depth analysis of all major field-assisted sintering techniques; Explains new techniques and approaches for material treatment; Provides detailed descriptions of spark plasma sintering, microwave sintering, high-voltage consolidation, magnetic pulse compaction, and various other approaches when field-assisted treatment is applied.




Freezing Colloids: Observations, Principles, Control, and Use


Book Description

This book presents a comprehensive overview of the freezing of colloidal suspensions and explores cutting-edge research in the field. It is the first book to deal with this phenomenon from a multidisciplinary perspective, and examines the various occurrences, their technological uses, the fundamental phenomena, and the different modeling approaches. Its chapters integrate input from fields as diverse as materials science, physics, biology, mathematics, geophysics, and food science, and therefore provide an excellent point of departure for anyone interested in the topic. The main content is supplemented by a wealth of figures and illustrations to elucidate the concepts presented, and includes a final chapter providing advice for those starting out in the field. As such, the book provides an invaluable resource for materials scientists, physicists, biologists, and mathematicians, and will also benefit food engineers, civil engineers, and materials processing professionals.




Complex Concentrated Alloys (CCAs)


Book Description

This book is a collection of several unique articles on the current state of research on complex concentrated alloys, as well as their compelling future opportunities in wide ranging applications. Complex concentrated alloys consist of multiple principal elements and represent a new paradigm in structural alloy design. They show a range of exceptional properties that are unachievable in conventional alloys, including high strength–ductility combination, resistance to oxidation, corrosion/wear resistance, and excellent high-temperature properties. The research articles, reviews, and perspectives are intended to provide a wholistic view of this multidisciplinary subject of interest to scientists and engineers.