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The bonding of gold and gold alloys to non-metallic materials
William S. Rapson
Gold Bulletin , 1979, DOI: 10.1007/BF03215110
Abstract: A number of industrial applications of gold are based upon the bonding of it or its alloys to non-metallic substrates. Such applications are reviewed in this article with special reference to the techniques employed and the bonding mechanisms which are involved.
TOPICAL REVIEW: Metallo-supramolecular modules as a paradigm for materials science
Dirk G Kurth
Science and Technology of Advanced Materials , 2008,
Abstract: Metal ion coordination in discrete or extended metallo-supramolecular assemblies offers ample opportunity to fabricate and study devices and materials that are equally important for fundamental research and new technologies. Metal ions embedded in a specific ligand field offer diverse thermodynamic, kinetic, chemical, physical and structural properties that make these systems promising candidates for active components in functional materials. A key challenge is to improve and develop methodologies for placing these active modules in suitable device architectures, such as thin films or mesophases. This review highlights recent developments in extended, polymeric metallo-supramolecular systems and discrete polyoxometalates with an emphasis on materials science.
Corrosion Behaviour of Fe/Co Based Amorphous Metallic Alloys in Saline Solutions: New Materials for GMI Based Biosensors
Marzo,F.F.; Pierna,A.R.; Barranco,J.; Vara,G.; Lorenzo,A.; Pérez,A.; García,J.A.;
Portugaliae Electrochimica Acta , 2007,
Abstract: the objective of this investigation has been the study of corrosion resistance of fe2.5co64.5cr3si15b15, fe3co67cr3si15b12 and fe5co70si15b10 amorphous metallic alloys obtained by the melt spinning technique, used as based materials to create a new type of giant magnetoimpedance (gmi) biosensor. the corrosion behaviour has been studied in phosphate buffered saline (pbs) solutions at ph 7.3 and 37.5 oc. the electrochemical characterization of alloys has been made by means of dc techniques, obtaining the corrosion potential, pitting and protection potentials, as well as the perfect and imperfect passive regions of alloys. in this work, the experimental results obtained are discussed in order to study their corrosion behaviour in artificial biological solutions and thus determine their possible use as gmi-biosensor prototype materials.
A generic method for modelling the behavior of anisotropic metallic materials : application to recrystallized zirconium alloys  [PDF]
S. Leclercq,Gilles Rousselier,Georges Cailletaud
Physics , 2007,
Abstract: A simplified polycrystalline model (the so-called RL model) is proposed to simulate the anisotropic viscoplastic behavior of metallic materials. A generic method is presented that makes it possible to build a simplified anisotropic material texture, based on the principal features of the pole figures. The method is applied to a recrystallized zirconium alloy, used as clad material in the fuel rods of nuclear power plants. An important database consisting in mechanical tests performed on Zircaloy tubes is collected. Only a small number of tests (pure tension, pure shear) are used to identify the material parameters, and the texture parameters. It is shown that six crystallographic orientations (6 "grains") are sufficient to describe the large anisotropy of such hcp alloy. The identified crystallographic orientations match the experimental pole figures of the material, not used in the identification procedure. Special attention is paid to the predictive ability of the model, i.e., its ability to simulate correctly experimental tests not belonging to the identification database. These predictive results are good, thanks to an identification procedure that enables to consider the contribution of each slip system in each crystallographic orientation.
Ferrimagnetism and antiferromagnetism in half-metallic Heusler alloys  [PDF]
I. Galanakis,K. Ozdogan,E. Sasioglu,B. Aktas
Physics , 2007, DOI: 10.1002/pssa.200776454
Abstract: Half-metallic Heusler alloys are among the most promising materials for future applications in spintronic devices. Although most Heusler alloys are ferromagnets, ferrimagnetic or antiferromagnetic (also called fully-compensated ferrimagnetic) alloys would be more desirable for applications due to the lower external fields. Ferrimagnetism can be either found in perfect Heusler compounds or achieved through the creation of defects in ferromagnetic Heusler alloys.
Coating and Surface Treatments on Orthodontic Metallic Materials  [PDF]
Santiago Arango,Alejandro Peláez-Vargas,Claudia García
Coatings , 2013, DOI: 10.3390/coatings3010001
Abstract: Metallic biomaterials have been extensively used in orthodontics throughout history. Gold, stainless steel, cobalt-chromium alloys, titanium and its alloys, among other metallic biomaterials, have been part of the orthodontic armamentarium since the twentieth century. Metals and alloys possess outstanding properties and offer numerous possibilities for the fabrication of orthodontic devices such as brackets, wires, bands, ligatures, among others. However, these materials have drawbacks that can present problems for the orthodontist. Poor friction control, allergic reactions, and metal ionic release are some of the most common disadvantages found when using metallic alloys for manufacturing orthodontic appliances. In order to overcome such weaknesses, research has been conducted aiming at different approaches, such as coatings and surface treatments, which have been developed to render these materials more suitable for orthodontic applications. The purpose of this paper is to provide an overview of the coating and surface treatment methods performed on metallic biomaterials used in orthodontics.
Pareto-optimal alloys  [PDF]
Thomas Bligaard,Gisli H. Johannesson,Andrei V. Ruban,Hans L. Skriver,Karsten W. Jacobsen,Jens K. Norskov
Physics , 2003, DOI: 10.1063/1.1631051
Abstract: Large databases that can be used in the search for new materials with specific properties remain an elusive goal in materials science. The search problem is complicated by the fact that the optimal material for a given application is usually a compromise between a number of materials properties and the price. In this letter we present a database consisting of the lattice parameters, bulk moduli, and heats of formation for over 64,000 ordered metallic alloys, which has been established by direct first-principles density-functional-theory calculations. Furthermore, we use a concept from economic theory, the Pareto-optimal set, to determine optimal alloy solutions for the compromise between low compressibility, high stability and price.
Changing Wisdom of Metallic Alloys Development  [PDF]
Manoj Gupta
Materials Sciences and Applications (MSA) , 2018, DOI: 10.4236/msa.2018.913074
Abstract: Metallic alloys have been instrumental through the ages in shaping the progress of human civilization. The development of the alloys from ancient to present time initiated from accidents to through the use of well-defined scientific principles. This article provides a snapshot of the alloys development from ancient to present time and the likely future direction.
Spin-polarization and electronic properties of half-metallic Heusler alloys calculated from first-principles  [PDF]
I. Galanakis,Ph. Mavropoulos
Physics , 2006, DOI: 10.1088/0953-8984/19/31/315213
Abstract: Half-metallic Heusler alloys are amongst the most promising materials for future magnetoelectronic applications. We review some recent results on the electronic properties of these compounds. The origin of the gap in these half-metallic alloys and its connection to the magnetic properties are well understood. Changing the lattice parameter shifts slightly the Fermi level. Spin-orbit coupling induces states within the gap but the alloys keep a very high degree of spin-polarization at the Fermi level. Small degrees of doping and disorder as well as defects with low formation energy have little effect on the properties of the gap, while temperature effects can lead to a quick loss of half-metallicity. Finally we discuss two special issues; the case of quaternary Heusler alloys and the half-metallic ferrimagnets.
Charge Distributions in Metallic Alloys: a Charge Excess Functional theory approach  [PDF]
Ezio Bruno
Physics , 2002, DOI: 10.1103/PhysRevLett.91.166401
Abstract: Charge Distributions in Metallic Alloys: a Charge Excess Functional theory approach
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