The Theory of Transformations in Metals and Alloys (Part I + II),
This book reveals the history of metals and alloys and their importance in prosthodontics. This book covers the review of literature, classification, discuss the metals and alloys and also the recent alloys used in prosthodontics.This book also revels the recent classification of the alloys according to ADA. This book explains each alloys properties,uses, compositions, advantages and disadvantages of each alloy.
Nowadays, the use of pure metals is quite limited in dentistry because they appear to be soft and may tend to corrode rapidly.To optimize properties, most of the metals commonly used in dental applications are mixtures of two or more metallic elements or one or more metals and/or non-metals. Although such mixtures can be produced in a number of ways. The use of these cast metals has decreased because of increased consumer demand for aesthetics over durability. Knowledge of the structure and properties of cast metals and alloys is essential to ensure proper handling of these materials. Thus this book is a compilation of all dental casting alloys and their applications in clinical dentistry.
New contributions to the cyclic plasticity of engineering materials Written by leading experts in the field, this book provides an authoritative and comprehensive introduction to cyclic plasticity of metals, polymers, composites and shape memory alloys. Each chapter is devoted to fundamentals of cyclic plasticity or to one of the major classes of materials, thereby providing a wide coverage of the field. The book deals with experimental observations on metals, composites, polymers and shape memory alloys, and the corresponding cyclic plasticity models for metals, polymers, particle reinforced metal matrix composites and shape memory alloys. Also, the thermo-mechanical coupled cyclic plasticity models are discussed for metals and shape memory alloys. Key features: Provides a comprehensive introduction to cyclic plasticity Presents Macroscopic and microscopic observations on the ratchetting of different materials Establishes cyclic plasticity constitutive models for different materials. Analysis of cyclic plasticity in engineering structures. This book is an important reference for students, practicing engineers and researchers who study cyclic plasticity in the areas of mechanical, civil, nuclear, and aerospace engineering as well as materials science.
Metal ion release from metallic materials, e.g. metallic alloys and pure metals, implanted into the human body in dental and orthopedic surgery are becoming a major cause for concern. This book briefly provides an overview of both metallic alloys and pure metals used in implant materials in dental and orthopedic surgery. Additionally, a short section is dedicated to important biomaterials and their corrosive behavior in both real solutions and various types of media that model human biological fluids and tissues. The present book gives an overview of analytical methods, techniques and different approaches applied to measurement of in vivo trace metals released into body fluids and tissues from patients carrying metal-on-metal prosthesis and metal dental implants. Reference levels of ion concentrations in body fluids and tissues that have been determined by a host of studies are compiled, reviewed and presented in this paper. Finally, a collection of published clinical data on in vivo released trace metals from metallic medical implants is included.
The growth of technology has placed rather severe demands on materials engineers to come up with novel materials at low cost to meet stringent and often contradictory property requirements which conventional materials cannot satisfy. In this respect,composite materials show great promise because of their superior stiness, high strength at elevated temperatures and better creep characteristics. Starting as early as 1906 the rotating isotropic disc has been studied by Grubler (1906)followed by Donatch (1912). Probably the first recognition given to the industrial importance of creep was by Dickenson in 1922. Experimental studies have demonstrated that steady state creep rate in aluminum or its alloys may be reduced by several orders of magnitude when it is reinforced with ceramic particles/whiskers like silicon carbide. The purpose of the present work is to study the isotropic and anisotropic properties with different distribution of material particulates. In many applications,rotating discs are exposed to elevated temperatures where creep deformation becomes important. From this point of view, an attempt has been made to analyze creep in rotating disc made of Al-SiC composites.
The present book included three of the published papers, which have been chosen in CSA's Mechanical & Transportation Engineering Abstracts Database, America, 2005. Also, one of the published paper has the name of " New lead free solder alloy". Also one paper has been published in Key to metals,2012. In this book, we explained some basic concepts of metallic alloys, types and applications of metallic alloys. Furthermore we explained the types of solder alloys. In addition, illustration the importance of the rapid solidification technology that is used for producing alloys with improved properties.
Mechanical vibrations of ultrasonic frequency exert a considerable influence upon the mechanical properties of metals, in particular, their deformation characteristics. The following three phenomena are considered: ultrasonic softening, ultrasonic hardening and the influence of preliminary ultrasonic treatment upon the steady-state creep of metals. Ultrasonic softening takes place when a ultrasonic loading is superimposed upon a static one, which results in the decrease of static load needed to deform the metal. Ultrasonic hardening occurs during the sonication of annealed material without a static loading. The ultrasonic hardening manifests itself in the increase of the yield strength of material due to the defects of crystalline structure nucleated and developed in acoustic field. Ultrasonic treatment consists of the ultrasonic irradiation of material and subsequent annealing. Materials treated in such a way can offer a considerable resistance to creep deformation. However, this tendency is not a monotonic function of the preliminary sonification parameters. A new theory, the synthetic theory of irrecoverable deformation, is employed to model the phenomena discussed above.
The text book entitled X-RAY DEBYE TEMPERATURE STUDIES OF METALS AND ALLOYS. This book is designed to meet the requirements of research students. This book has been divided into five parts: 1.Theoretical explanation: Theoretical explanation of Debye-Waller factors, Debye temperatures and mean square amplitude of vibrations data included, 2.Experimental: Experimental data with suitable diagrams and equations included 3.Few Additional Chapters : related additional chapters (crystallograpghy-crystal structure, X-ray diffraction, Nanomaterial) added. The Debye-Waller factors and Debye temperatures of crystals are parameters of lattice dynamical interest. The experimental determination of these parameters by the X-ray diffraction technique is the objective of an on-going programme in this book. So far the Debye-Waller factors and Debye temperatures have been determined for a large number of materials possessing different crystal structures. I express my deep sense of gratitude to my beloved teacher and Research Supervisor Prof. N. Gopi Krishna, Department of Physics, Kakatiya University, Warangal for his inspiration, creative encouragement and constructive guidance throughout my work
Positron annihilation spectroscopy is non-destructive method for studying defects in solid state materials. Binary alloys of iron and aluminium are industrially interesting materials and are suitable candidate for studying the behavior of intermetallics with vacancy concentrations several orders higher than in pure metals. Measuring of the positron lifetime enables to classify defects type, volume size and concentration. Measuring of coincidence Doppler broadening of annihilation peak carries information about chemical environment of a positron trapped at the defect. These measurements are supported by quantum-mechanics theoretical calculations which help us to interpret the measured data. Mechanical properties were studied simultaneously by the measuring of Vickers microhardness and compared with the positron annihilation spectroscopy results. The correlation of defect concentration with mechanical properties was observed in Fe-Al alloys with various composition and after various thermal treatments.
This work presents a new formulation of the Boundary Element Method (BEM) for nonlinear time-dependent problems. An incremental process, in order to reach the steady state condition and the secondary steady stage for visco-plasticity and creep respectively, has also been developed. This research includes the development of a new Boundary Element Formulation for analysis of fracture problems related to visco-plasticity and creep. For the visco-plastic and creep crack analysis the Dual Boundary Element Method, (DBEM) is formulated. The implementation of visco-plasticity and creep in the formulation is taken into account by domain integrals in both boundary integral equations. The creep analysis is basically applied to metals, and this is confined to standard power law creep equations. Constant applied loads are used to demonstrate time and strain hardening effects. The calculation of the modified fracture parameter J-Integral, which is called C(t)-Integral for creep analysis, is obtained by applying this method to crack problems. This book is appropriate for researchers, Ph.D. and postgraduate students involved in modern numerical methods and non-linear analysis.
A filling is the repair of a damaged or decayed tooth, restoring it back to its normal shape, appearance and function. Amalgam Restoration is an example of the material giving its name to the process. Amalgam fillings are made up of mercury, powdered silver and tin. They are mixed and packed into cavities in teeth where it hardens slowly and replaces the missing tooth substance. The high copper have become material of choice as compared to low copper alloys nowadays because of their improved mechanical properties, corrosion resistance, better marginal integrity and improved performance in clinical trial. The high copper amalgam was used as a restorative material and was found to be much more useful than low copper amalgam. High copper had much more strength, corrosion resistance, durability and resistance to tarnish as compared to low copper amalgams. No marked expansion or condensation was noted in the amalgam restoration after its setting after 24 hrs. By using the high copper alloy, the chances of creep were also minimized in the restored tooth. No discomfort or any kind of odd sensation in the tooth was noted after few days of amalgam restoration in the tooth.
Summary: Materials are the essential part of our daily life and civilizations have been known by the materials they introduced. As the science progressed, scientists used the different combinations of material to enhance their properties to cope with new challenges and requirements. Alloys are also the combination of different materials specifically of metals. In early ages Iron and their alloys were used in the manufacturing heavy machineries. Gradually elements of lighter weight replaced the ferrous material like Alloys of Mg and Al. The main focus of this book will be on Aluminum Alloys specifically on Aluminum Alloy 2024. Aluminium alloys called super alloys because of their preferable mechanical and chemical properties for wide range of applications and uses. 2024 aluminium alloy was fabricated by taking percentage weight composition of Al-Cu-Mg-Zn.Corrosion tests were performed in 0.1M NaCl, 1% aqua regia and 5% aqua regia, 1% Potassium Dichromate solution and weight change was recorded in different intervals of time. Corrosion rate was studied by using Atomic Absorption Spectroscopy and morphological studies was accomplished by using Optical Microscopy.
A consideration has been given to dynamic models of formation of martensite plates with a fine structure of transformation twins, which are compatible with the supersonic growth rate of martensite crystals. Along with relatively long quasi-longitudinal waves, which determine the orientation of the habit plane, the control wave process includes relatively short longitudinal waves, which act in synchronism and control the growth of the main component of a regular twin structure. Preference is given to a model containing, at the initial moment of time, the only active dynamic cell capable of periodic reproduction in the interphase region at the stage of the martensite crystal growth. The calculated macroscopic morphological attributes, which were deduced from dynamic considerations, have been compared with the experimental data and crystallogeometrical calculation. Discussion of results and conclusions in a final part of the monography represent the independent interest. For scientific employees and experts in the field of metallography and physics of metals and alloys, as well as teachers, post-graduate students and the students who are specializing in materials technology.
Fundamentals and Practices in Colouration of Textiles
With the advancements in technology more & more artificial metals, alloys and other implantable and non implantable materials are being used in the fields of medicine and dentistry. These materials directly or indirectly come in contact with skin, epithelium, connective tissue or bone. Given this long term intimate contact with vital tissues, it is paramount that alloy biocompatibility be investigated and understood. Moreover the oral and maxillofacial environment is complex and varied with different requirement and biocompatibility issues depending on the specific use. Unfortunately in our educational curriculums these important issues are not thoroughly understood, investigated or taught. In this book authors have made an utmost effort to make readers get a fair idea about these important issues and discuss the recent researches in this field. This will surely be a very useful piece of work for the medical and dental students, practitioners, assistants, technicians, manufacturer and many others who directly or indirectly come in contact with these materials.
Nanomaterials have wide range of applications such as catalysis,medicine, electronics, lubricants, medical implants, water purification, fuel additives, energy production etc. Studies on nanomaterials, such as transition metal oxides, cobaltite, ferrites, metals and their alloys have been undertaken. Chapter 1 includes general information about nanomaterials, their properties, classification (1D, 2D and 3D) on the basis of dimensions, significance of materials on nano scale and their applications. Several methods of synthesis of nanomaterials such sol-gel, co-percipitation, template synthesis etc. along with detail of various techniques used for their characterization such as TEM, SEM, HRTEM, XRD etc. Studies embodied in Chapter 2 isabout ammonium perchlorate, their Properties, and Mechanism of thermal decomposition and effect of metal and alloys on their thermal decomposition of AP are also discussed. Details about AP based propellants are included. Components like oxidizer, meral fuel, binder, plasticizer modifier, curing agent and properties of propellants are mentioned.
One of the most important quantities characterizing a liquid metal is the static structure factor, S(k), i.e., the Fourier transforms of the pair correlation function g(r). A detailed knowledge of this quantity is essential for a quantitative understanding not only of the structure of fluid but also of numerous other properties of liquid metals and their alloys. There is an increasing need for understanding the various properties of metals, oxides and salts in the liquid state, because of their important role in metallurgical processes. The main problem in studying the properties of liquid metals is the non-availability of the exact interatomic potential. There are great uncertainties associated with the ab initio calculations of liquid metal interactions. Thus, although we can borrow the techniques of classical statistical mechanics, up to some extent, but unsure of the potential to which they are to be applied. The objective of this work is to determine the static structure factor for some liquid metals described in the long-wavelength limit and then its corresponding structure factor.