Synthesis of nonequilibrium metallic phases has been an area of great interest to the materials processing community since early 1960. Inherent rapid cooling rates in laser processing are being used to engineer non-equilibrium microstructures which cannot be rivaled by other processes. This lecture will discuss the phenomena involved and its application in designing materials with tailored properties. What is non-equilibrium Synthesis? This is a synthesis method to produce binary or higher order materials where kinetics of the pro cess affects the transport of the constituent elements during phase transformation resulting in a composition or crystallographic configuration which is different from what is observed when the elements arranges themselves with the lowest possible Gibbs Free energy, which is the equilibrium condition. Figure 1 illustrates the phenomena. Phase diagram under equilibrium condition is illustrated by the solid line whereas the no-equilibrium phase diagram is represented by the dotted line. One can observe the shrinkage of the phase field under non-equilibrium condition. Any alloy composition between the solidus lines of the equilibrium and non-equilibrium phase diagram will be a non equilibrium alloys with extended solid solution.

Synthesis of nonequilibrium metallic phases has been an area of great interest to the materials processing community since early 1960. Inherent rapid cooling rates in laser processing are being used to engineer non-equilibrium microstructures which cannot be rivaled by other processes. This lecture will discuss the phenomena involved and its application in designing materials with tailored properties. What is non-equilibrium Synthesis? This is a synthesis method to produce binary or higher order materials where kinetics of the pro cess affects the transport of the constituent elements during phase transformation resulting in a composition or crystallographic configuration which is different from what is observed when the elements arranges themselves with the lowest possible Gibbs Free energy, which is the equilibrium condition. Figure 1 illustrates the phenomena. Phase diagram under equilibrium condition is illustrated by the solid line whereas the no-equilibrium phase diagram is represented by the dotted line. One can observe the shrinkage of the phase field under non-equilibrium condition. Any alloy composition between the solidus lines of the equilibrium and non-equilibrium phase diagram will be a non equilibrium alloys with extended solid solution.

The current status of the science and technology related to coatings, thin films and surface modifications produced by directed energy techniques is assessed in Materials Surface Processing by Directed Energy Techniques. The subject matter is divided into 20 chapters - each presented at a tutorial level – rich with fundamental science and experimental results. New trends and new results are also evoked to give an overview of future developments and applications. - Provides a broad overview on modern coating and thin film deposition techniques, and their applications - Presents and discusses various problems of physics and chemistry involved in the production, characterization and applications of coatings and thin films - Each chapter includes experimental results illustrating various models, mechanisms or theories

Proceedings of the NATO Advanced Study Institute, San Miniato, Italy, September 2-13, 1985

Corrosion and erosion processes often occur synergistically to cause serious damage to metal alloys. Laser surface modification techniques such as laser surface melting or alloying are being increasingly used to treat surfaces to prevent corrosion or repair corroded or damaged components. Laser surface modification of alloys for corrosion and erosion resistance reviews the wealth of recent research on these important techniques and their applications.After an introductory overview, part one reviews the use of laser surface melting and other techniques to improve the corrosion resistance of stainless and other steels as well as nickel-titanium and a range of other alloys. Part two covers the use of laser surface modification to prevent different types of erosion, including liquid impingement, slurry (solid particle) and electrical erosion as well as laser remanufacturing of damaged components.With its distinguished editor and international team of contributors, Laser surface modification of alloys for corrosion and erosion resistance is a standard reference for all those concerned with preventing corrosion and erosion damage in metallic components in sectors as diverse as energy production and electrical engineering. - Reviews recent research on the use of laser surface modification techniques, including the prevention of corrosion and repair of corroded or damaged components - Discusses the techniques for improving the corrosion resistance of steels, nickel-titanium and a range of alloys - Analyses the use of laser surface modification to prevent different types of erosion, including liquid impingement and laser remanufacturing of damaged components

The rapid development of laser sources opens up new and fascinating ways for using light as a tool to characterize and modify surfaces and thin films. Quite remarkable progress is being made in improving lasers in their performance with respect to power, tunability, or generation of ultrashort light pulses. In particular, the application of laser diodes both as a direct light source and for pumping other laser materials is flourishing. Among the laser methods for surface treatment and modification a large variety of processes are under investigation, such as etching by laser induced chemical reactions, annealing and cleaning of semiconductor surfaces, or the maskless production of submicron periodic structures. Also film deposition by means of laser processing is widely being used, including high temperature superconductors and diamond like films. In laser diagnostics new time domains have become accessible by optical microscopy with femtosecond light pulses, and nonlinear effects are exploited e.g. to characterize adsorbates by their nonlinear optical response, or magnetic interfaces by means of the nonlinear magnetooptic Kerr effect. New materials with characteristic dimensions on nanoscopic scales - a particularly prominent example being porous silicon - are attracting tremendous attraction due to quantum size effects which give rise to novel optical phenomena not observed in the corresponding bulk materials. As a result of this wealth of developments it is difficult yet essential to obtain thorough reviews of the field, covering fundamental aspects as well as applications. For the latter, it is also very important to realize which processes are already well accepted in industry, which phenomena may not be so suitable for industrial purposes, and which are the most desirable new directions to go.

New chapters on bending and cleaning reflect the changes in the field since the last edition, completing the range of practical knowledge about the processes possible with lasers already familiar to users of this well-known text. Professor Steen's lively presentation is supported by a number of original cartoons by Patrick Wright and Noel Ford, which will bring a smile to your face and ease the learning process. From the reviews: "...well organized, and the text is very practical...The engineering community will find this book informative and useful." (OPTICS AND PHOTONICS NEWS, July/August 2005)

This book describes the basic mechanisms, theory, simulations and technological aspects of Laser processing techniques. It covers the principles of laser quenching, welding, cutting, alloying, selective sintering, ablation, etc. The main attention is paid to the quantitative description. The diversity and complexity of technological and physical processes is discussed using a unitary approach. The book aims on understanding the cause-and-effect relations in physical processes in Laser technologies. It will help researchers and engineers to improve the existing and develop new Laser machining techniques. The book addresses readers with a certain background in general physics and mathematical analysis: graduate students, researchers and engineers practicing laser applications.

This text aims at providing a comprehensive and up to date treatment of the new and rapidly expanding field of laser pro cessing of thin films, particularly, though by no means exclu sively, of recent progress in the dielectrics area. The volume covers all the major aspects of laser processing technology in general, from the background and history to its many potential applications, and from the theory to the necessary experimental considerations. It highlights and compares the vast array of processing conditions now available with intense photon beams, as well as the properties of the films and microstructures pro duced. Separate chapters deal with the fundamentals of laser interactions with matter, and with experimental considerations. Detailed consideration is also given to film deposition, nuclea tion and growth, oxidation and annealing, as well as selective and localized. etching and ablation, not only in terms of the various photon-induced processes, but also with respect to traditional as well as other competing new technologies.

The book provides a unique overview on laser techniques and applications for the purpose of improving adhesion by altering surface chemistry and topography/morphology of the substrate. It details laser surface modification techniques for a wide range of industrially relevant materials (plastics, metals, ceramics, composites) with the aim to improve and enhance their adhesion to other materials. The joining of different materials is of critical importance in the fabrication of many and varied products.