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Prologue
Published in Alan Cottrell, An Introduction to Metallurgy, 2019
Metallurgy is the art and science of making metals and alloys in forms and with properties suitable for practical use. Most people know it only as an ancient and mysterious art. Certainly it had a place in ancient history, having brought us out of the Stone Age into the Bronze Age and then into the Iron Age. The seemingly miraculous conversion of dull earths into shining metals was the very essence of alchemical mystery; and there was no science of metals to bring rationality and enlightenment into the mediaeval world of secret formulae for tempering metals and blending alloys.
Converting Minerals to Metals
Published in Karlheinz Spitz, John Trudinger, Mining and the Environment, 2019
Karlheinz Spitz, John Trudinger
Mineral processing or extractive metallurgy includes all activities and processes required to extract valuable minerals from their ores to produce pure metals. Metals are rarely found in their native metal form, gold being a notable exception. Most other metals exist as oxide, sulphide or silicate minerals, and these must be reduced to extract metals. Mineral processing plants usually combine a number of methods to extract and to purify metals.
Heat Treatment by Induction
Published in Valery Rudnev, Don Loveless, Raymond L. Cook, Handbook of Induction Heating, 2017
Valery Rudnev, Don Loveless, Raymond L. Cook
Metallurgy as an art has been practiced since the beginning of the history of mankind, but as a science, it traces its origin to the early 1860s when light optical microscopy began to be used to inspect the structure of metals and alloys. Metallurgy is a broad term that can be defined as a domain of science that deals with the process of extracting metals from the ores in which they are found, followed by its refining, alloying, developing desirable structures, obtaining needed properties, and fabricating useful objects.
A game approach to the parametric control of real-time systems
Published in International Journal of Control, 2019
Aleksandra Jovanović, Didier Lime, Olivier H. Roux
Let us consider the copper annealing controller depicted in Figure 3. Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered, causing changes in its properties such as strength and hardness. It is a process that produces conditions by heating to above the critical temperature, maintaining a suitable temperature, and then cooling.
Design optimization of conformal cooling channels for injection molds: 3D transient heat transfer analysis
Published in Mechanics of Advanced Materials and Structures, 2023
Hugo Miguel Silva, João Tiago Noversa, Leandro Fernandes, Hugo Luís Rodrigues, António José Pontes
Optimization is a discipline of applied mathematics concerned with discovering the extremal value of a function in a given domain while taking into consideration a variety of variable value constraints [27]. In the past two decades, global optimization has received considerable attention. Frequently, the objective function is nonlinear and nonconvex. Numerous local minimums are commonly encountered. Consequently, traditional nonlinear programming approaches may be unable to locate the global minimum [28]. The global optimization issue involves locating a point x in a solution space set X (also known as the feasible area) where a given function f: XT (also known as the objective function) reaches a minimum or maximum. In 1953, Metropolis et al. [29] developed the Monte Carlo method for “calculating the characteristics of any material presumed to be composed of interacting individual molecules.” This "Metropolis" technique based on statistical mechanics might be used to simulate how metal crystals reorganize and reach equilibrium during the annealing process. In the early 1980s, Kirkpatrick et al. [30] were inspired to develop and use the simulated annealing1 (SA) global optimization method to a wide range of combinatorial optimization problems. Cerny [31] and Kuo and Chen [32] and Kuo and Qiu [33] approached the traveling salesman problem in a comparable manner. The optimization approach of Simulated Annealing may be used to solve issues in a range of search and problem areas. Simulated annealing, similar to simple hill climbing algorithms, begins with a single individual and a unary search procedure. In the fields of metallurgy and material science, annealing2 is a heat treatment used to modify a material's properties, such as its hardness. Ion dislocations, for instance, damage the overall structure of metal crystals. When the metal is heated, both the ions’ energy and their diffusion rate increase. As the substance cools and achieves equilibrium, dislocations may be removed, and the crystal structure can be restored. When annealing metal, the starting temperature should not be too low, and cooling should occur slowly enough to avoid trapping the system in a meta-stable, noncrystalline state that represents a local energy minimum.