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1–10 of about 1040 matches for metallurgy
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Aluminum Matrix Composites Reinforced with Si3N4, AlN and ZrB2, Produced by Conventional Powder Metallurgy and Mechanical Alloying (20072307)
KONA Powder & Particle N22 P143-150
The homogenous distribution of the reinforcement phase is a prime requisite for a composite material to present its superior performance. Powder metallurgy can produce composite materials in the whole range of matrix reinforcement composition, without the segregation typical of the casting process, and mechanical alloying serves to optimize the particle mixing stage, enhancing the reinforcement distribution. This work investigates the use of mechanical alloying plus hot extrusion to obtain Al6061 matrix composites reinforced with Si3N4, AlN and ZrB2, and compares the result with the same composite materials obtained by more conventional powder metallurgy techniques. The incorporation of the reinforcement does not suffice to produce a significant improvement of the mechanical properties of the conventional powder metallurgy composites. Mechanical alloying breaks the reinforcement particle clusters, eliminates most of the defect present in these particles, decreases their size and enhances their distribution, which together with the metallurgical phenomena that change the metallic matrix, such as work hardening and oxide and carbide dispersion, produces an increase of about 150% in the hardness of the powder when compared with the hardness of the as-received, non-reinforced aluminum powder alloy; and of 100% in the hardness and ultimate tensile strength of the consolidated materials, when compared with material of same composition processed by conventional powder metallurgy.

METALLURGY OF MALLEABLE IRON (19710933)
Available from the Malleable Founders Society, Cleveland, OH
This 94 page informative booklet contains basic up-to-date facts on the metallurgy of malleable iron. It covers pure iron, the temperature effect on pure iron, effect of carbon and silicon, solidification of malleable iron and mottling. It also covers the influence of composition and processing on annealing, nucleation along with the influence of various elements on malleable iron. The production of pearlitic malleable iron is discussed with the stages of graphitization. It concludes with a discussion of the hardening of malleable iron. The booklet contains a bibliography of 127 references to the metallurgy of malleable iron.

INFERENTIAL MODEL OF DESULFURIZATION FOR LADLE METALLURGY (20050448)
60th Electric Furnace Conference Proceedings – November 10-13, 2002, San Antonio, TX – Energy and Environment I
Feedback data from a process is important in achieving control of that process. Feedback data is used by the control system to determine the subsequent action on the manipulated variables. For example, metal analysis of a sample taken from a ladle is often used by the operator to make a judgment about the amount of stirring required in the remaining time. Automated control systems rely on algorithms rather than operator judgment but the principal is the same. When a measurement of the variable being controlled is not available in real time, an inferential model can be used. In the case of ladle metallurgy, it is very difficult to obtain reliable real time measurement of important variables such as metal chemistry, slag chemistry, temperature and stirring energy. An inferential model can be used to provide an estimate value of the process variable, which in turn can be used as feedback data to the control system. This principal is well established in process control engineering and has been applied to various metallurgical processes.

PROCESS METALLURGY - FUTURE (19870836)
Transactions of the American Foundrymen's Society V 95 Paper 87-13 P 431-434, 1987 (4 p)
This paper reviews the major areas of process metallurgy affecting steel castings in general and highlights two areas specifically, that of gating systems and advanced melting techniques as they may contribute to reductions in the macroinclusion problem. Briefly covered are bottom pour nozzles and shrouds, gating system design, inmold deoxidation, melt processing, ladle desulfurization and computer governed process controls. Many of the innovations will become standard practice in the short term (within five years) while advanced melting technologies will be accepted as their contributions to quality are recognized.

THE DEVELOPMENT TRENDS IN THE DUCTILE IRON METALLURGY (19970490)
The Institute of Indian Foundrymen 45th Indian Foundry Congress Proceedings P 341-370, Jan 1997 (30 p)
The article provides a comprehensive overview of the production and metallurgy of ductile iron, including the history of the material. Commercially, ductile iron became a production-viable material in the late 1940s; however, the first known ductile iron was produced by Chinese foundrymen approximately 2000 years ago. Worldwide, the cupola is used to produce more than 60% of the base iron. The article also describes factors affecting casting shrinkage and metallurgical microstructures.

Metallurgy Under High Pressure – The New Process in Foundry Practice (20082672)
Foundry – Science & Practice V1730-2250 P28-32
Some of the major achievements of Institute of Metal Science, Bulgarian Academy of Sciences in Sofia in the field of high nitrogen steels and, in general, in metallurgy under high pressure are briefly described. Composition and properties of a number of the steels are given. Installations for high pressure processing, available in IMS, are shown together with their technical characteristics. In the end, some particular applications of high nitrogen steels are discussed.

Dust Injection in Iron and Steel Metallurgy (20082891)
ISIJ V46 N12 P1745-1751
The occurrence of dusts in steelworks is surveyed. A brief overview of the European legislation situation is given. Current techniques of solid injection in different aggregates are presented. The investigations of the Department of Ferrous Metallurgy (IEHK) at RWTH Aachen University in the handling of various dusts in metallurgical processes are introduced. The dust injection into shaft furnaces and steel melts has been chosen as typical treatments. Former researches and recent works are presented and the results are discussed.

METALLURGY FOR DIE CASTERS (19840913)
Die Casting Engineer V 28 N 5 P 68, 70, 72 Sept/Oct 1984 (3 pages)
Article reviews the basic principles of metallurgy as they apply to a die caster. Covered are alloys and their constituents such as Si, Cu, Fe and their effects upon properties and behavior of the alloy during de casting operations. Of interest is a section on sludging, an effect of the heavier elements in an alloy such as the beta group in Al die casting alloys. Suggestions are offered to reduce metal loss due to sludging. Article concludes with brief summaries on heat treatment and modern melt filtering practices.

FOUNDRY SIZE LADLE METALLURGY VESSEL: FERROMANGANESE DISSOLUTION (20051004)
Transactions of the American Foundry Society V 113 Paper 05-080(09) P 985 - 996 (12 p)
This paper examines the dissolution rate of low carbon ferromanganese in steel. Forty-five kilogram (100 pound) heats were induction melted and poured into an unfired vessel fitted with a bottom porous plug for argon stirring. Alloy additions were made and timed samples taken to evaluate the effect of different gas flow rates, alloy particle sizes, and alloy concentrations on dissolution rate. In this study, it was found that for alloying to a nominal 0.30% manganese, ferroalloy particle size was more important to dissolution kinetics than gas flow rate, for the conditions examined. When alloying to 1.0% manganese, no clear correlation was observed due to alloy particle agglomeration. Activation energy could not be determined because of the rapid cooling during the experiments.

Effects of Near-Surface Metallurgy on Machinability of Gray Cast Iron (20083237)
AFS Transactions 2008, Vol. 116, Paper 08-139(05), P759-767
A technique for measuring cutting tool forces in facing cuts has been developed. The current study implemented a computer numerically controlled tool force measurement system and microstructure analysis. The specific cutting energy has been shown to decrease sharply as the cutting path occurs at a greater distance from the casting surface. Metallography of the near surface regions of the casting is quantitatively evaluated and compared to the variation of specific cutting energy with distance from the surface.

1–10 of about 1040 matches for metallurgy
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