Metallurgy Commons^™

Preparation And Separation Of Metallic Chlorides, Norbert Felix Neumann

Doctoral Dissertations

"The use of chlorine and chlorine compounds as metallurgical reagents has long been known to the metallurgical industry. Recent developments in corrosion resistant metals and alloys as well as new equipment and techniques have led to a revival of chlorine processes. Many of the objections to the use of chlorine in metallurgical operations have been overcome and many are being reconsidered, as evidenced by the new processes in which chlorine and chlorides are the primary reagents. The Betterton process employs chlorine or lead chloride for the dezincing of lead. Ductile zirconium and titanium have been made by reducing their chlorides …

Deposition Of Metallic Coatings From Fused Salt Baths, Andrew Hessler Larson

Masters Theses

"This thesis is the result of an investigation undertaken to study some of the important factors affecting the deposition of metallic diffusion coatings on other metals immersed in a fused salt bath….

There are many methods which have been devised to obtain diffusion coatings on various metals. One which is quite well known and used commercially is the process of “chromizing” which produces a diffusion layer if chromium on another metal. One method of “chromizing” consists of immersing the specimen to be coated in a mixed chloride fused bath containing chromium metal flakes. Another method consists of packing a low …

Effect Of Carbon Content In Steels Upon The Deposition Of Titanium From A Fused Salt Bath, Reinhard Paul Abendroth

Masters Theses

"STATEMENT OF PROBLEM Previous work done at the Missouri School of Mines and Metallurgy on the deposition of titanium upon various metals, especially iron and steel, bas shown that titanium can be deposited upon ingot iron and. low carbon steels with comparitive ease. Difficulty was encountered in attempts to deposit titanium upon steels of higher carbon content and upon cast irons.

For this reason, it was decided to investigate more thoroughly the relationship between the carbon content of various steels and the quality of titanium coatings deposited on these steels. Once this relationship had been established, a suitable theoretical explanation …

Corrosion Products Of Titanium In Fused Salt Baths, Kai-Chai Chiou

Masters Theses

"Titanium is gaining great interest in the modern metal industry because of its natural abundance and its desirable physical and chemical properties. Among them, its excellent corrosion resistance, such as the resistance to normal atmosphere attack, humid and saline atmosphere attack, sea water attack, and nitric acid attack, is the most prominent characteristic being welcomed by the engineers. The usefulness of titanium would be greatly increased if it were possible to plate titanium on other metals, thus increasing the corrosion resistance of these other metals.

Much concern, at present, has been given to the possibilities of the electrodeposition of titanium …

Mechanism And Measurement Of First Stage Graphitization In White Cast Iron, David S. Gould

Masters Theses

"The original object of this thesis was to ascertain if coercive force measurements could be used for the determination of degree of malleablization in malleable iron. Since first stage graphitization was involved, it was only natural that an interest in the mechanism of first stage graphitization developed. The investigation which resulted from this interest was done primarily for the edification of the author, however it was subsequently deemed of enough importance to be included in this thesis. For this reason the thesis may appear at times to deviate from the original objective"--Preface, page iii.

The Rate Of Dissolution Of Aluminum In Hydrofluoric Acid, Yen-Ngen Wang

Doctoral Dissertations

"Pure aluminum has a relatively low strength, and its use is, therefore, rather limited. However, the resistance of pure aluminum to the attack of acids and many neutral solutions is higher than that of less pure aluminum or most of the aluminum-base alloys. For this reason, alclad alloy sheets, are made with a coating of pure aluminum on one or both sides of an aluminum alloy core. The coating is metallurgically bonded to the core over the entire area of contact. Thus the coating electrochemically protects the core from corrosive attack.

Aluminum is more negative in the electrochemical series than …

Hydrogen Overvoltage On Titanium, Sheng-Tai Shih

Doctoral Dissertations

"The hydrogen overvoltage has been defined as the difference between the potential of the working electrode (cathode) and the theoretical reversible value for the same solution. This definition brings out the difficulty involved in the measurement of the "theoretical reversible potential for the same solution” as the potential of the hydrogen electrode in such a solution is usually different from the value of a standard reversible hydrogen electrode, for which the activity of hydrogen ions is set as being “1” and the potential arbitrarily set as being “0”. Besides, it is sometimes necessary to add addition agents to the solution …

A Study Of The Deformation Texture And Its Variation In Cold Drawn Nickel Rods, Krishan Kumar Tangri

Doctoral Dissertations

"The production of rods by cold drawing is a development of recent years as compared to other methods of fabrication. Though a good many investigations correlating the observed mechanical properties to the mill practices employed have been reported, the results nevertheless are more of a qualitative and empirical nature. It is well known that the physical properties of a metal product are related to its deformation textures which are characteristic of the metal and the fabricating method used. Thus a study of the deformation textures of cold-drawn rods, specially by x-ray diffraction techniques should provide a much more precise and …

The Preparation Of Zirconium Powder, Herbert S. Kalish

Professional Degree Theses

"The preparation of zirconium powder by several different methods is fully described and evaluated. Most of the methods described are of a rather classical nature and these methods are discussed as taken from their original sources with suggestions for possible streamlining. Flow sheets are provided.

The first series of steps to produce zirconium powder is almost invariably the production of pure zirconium tetrachloride or pure zirconium oxide from the tetrachloride. The processes described include the sodium reduction of zirconium tetrachloride, sodium reduction of the double alkali fluorides, the calcium reduction of zirconium oxide, hydrogen embrittlement and comminution of reduction products. …

The Lattice Constant And Coefficient Of Expansion Of Chromium, Chao-Ching Weng

Masters Theses

"The most important use of chromium, other than as an alloying element in the manufacture of stainless steel, is for electroplating; to form a coating on other metals for corrosion prevention in order to procure longer life, and to achieve a decorative effect.

The physical properties of chromium are important in the effectiveness of its uses, and its lattice constant, as well as coefficient of thermal expansion, seem worthy of exact determination.

A number of research workers, over a span of thirty years, have spent considerable effort in determining the aforementioned constants. However, their results do not check, and the …

Vapor Pressures & Relative Stabilities Of Certain Double Flourides, Walter L. Gage

Missouri School of Mines and Metallurgy Reports

The vapor pressures and relative stabilities of certain double fluorides such as sodium titanium fluoride and strontium titanium fluoride will be investigated by heating them under vacuum to determine the extent of evaporation or decomposition.

An Investigation Of The Deformation Textures Of Titanium, Dean Nesbit Williams

Doctoral Dissertations

"With the increase in production of titanium in recent years has come a great interest in the mechanical properties and in the possible uses of this metal. Due to the affinity of titanium for oxygen, nitrogen, carbon, and hydrogen, and the market effect of these elements on the mechanical properties, much of the work previously reported is unreliable. As purer commercial grades of titanium and high purity iodide titanium have become available for examination, research has been undertaken to correct and expand the knowledge of the properties of titanium. Although the uses of titanium are limited at the present time, …

The Effect Of Impeller Speed And Air-Volume On The Flotation Rate With Respect To Particle Size, William Edward Horst

Masters Theses

"Today the ore being mined is low grade and the mineralization has become very complex. In order to concentrate a complex ore, the requirement of grinding the ore very fine is imposed. The process of flotation was developed to concentrate the finely ground ore particles; however, the finer size fractions of the ore still present a concentrating problem.

The fact has been established that the flotation rate which is the recovery that can be attained during a given time interval varies with particle size. The flotation rate increases with an increase in particle size until the maximum flotation rate is …

X-Ray Studies Of Zirconium Cyanonitride, John T. Ballass

Masters Theses

"The purpose of this research was to study, by means of x-ray and metallographic analysis, a material reported to be zirconium cyanonitride.

The x-ray analysis had a three fold purpose, the determination of the symmetry of the constituents, the number of phases present, and the crystal structure type. Metallography was used to confirm some of the results obtained by x-ray analysis establishing certain definite phase relationships present in the microstructure.

The sample investigated contained three principal elements namely zirconium, nitrogen, and carbon. On the basis of constitution this work is a contribution toward the development of the three component equilibrum …

Direct Reduction Of Zinc Sulfide Under Vacuum, Merritt E. Langston

Masters Theses

"The present work is a continuation of the previous investigations of Gross and Warrington and Liu in which the effect of various reducing agents on the vacuum reduction of zinc sulfide was studied. The author became interested in this topic while reading the papers by these investigators in which they recommended that further work be performed in an attempt to prevent zinc sulfide from distilling over during reduction, thereby contaminating the zinc condensate. The original plan was to perform a few runs for the purpose of duplicating the results that were reported by Liu, and from this point carry on …

Dissociation And Relative Stability Of Sodium Fluotitanate, Walter L. Gage

Masters Theses

"Titanium is urgently needed in the armament industry especially as a substitute for 18-8 stainless steel. There would be an almost inexhaustible supply of ores of titanium if high-purity titanium metal could be produced economically in large quantities. The use of titanium would permit much of the scarce nickel and chromium to be made available for other important uses.

It has been found by H. C. Kawecki and E. J. Bielecki that high-purity Na₂TiF₆, K₂TiF₆, and (NH4)₂TiF₆ can be produced from iron-bearing titaniferous raw material, ilmenite ores, or a …

Activation Energy For Recrystallization In Rolled Silver, Krishan Kumar Tangri

Masters Theses

"In several metals the process of recrystallization is accompanied by a change in the orientation of the recrystallized material with respect to the cold rolled material. If the change is sufficiently large, the changing position of the crystals can be determined by measuring the change in the intensity of the characteristic Bragg-reflection with a Geiger counter x-ray spectrometer. Recent determinations of the activation energies of copper and a 50/50 iron-nickel alloy have been made by using this x-ray technique. Both of these metals show a decided shift in the orientation as the material is recrystallized.

Silver was examined to find …

A Study Of The Dissolution Of Titanium In Acids With Ammonium Fluoride Added, Charles Burroughs Gill

Doctoral Dissertations

"Titanium can no longer be considered a rare metal, even though the modern era of its production came into being only a few years ago. The first discovery of titanium was in 1791 by an English clergyman, the Reverend William Gregor, and the name titanium became universally adopted when so called by a German mineralogist, Martin Klaproth, who rediscovered titanium three years later. Not until 1887 was the relatively pure, 75 percent, metal prepared by L. F. Nilson and O. Pettersson, whose experiments were repeated in 1910 by M. A. Hunter. Hunter is given credit for producing the first metallic …

Direct Reduction Of Zinc Sulfide Under Vacuum -- Course Work, Merritt E. Langston

Missouri School of Mines and Metallurgy Reports

A study of the reduction of zinc sulfide under vacuum by such reducing agents as iron, calcium oxide and carbon, graphite, and iron and carbon.

An attempt to refine the impure zinc metal condensates obtained from the above reductions under under by the mechanism of a differential displacement of the volatile constituents.

Progress Report: Reduction Of Zinc Sulfide, Merritt E. Langston

Missouri School of Mines and Metallurgy Reports

To date the work which has been completed has been concerned with an attempt to duplicate the results reported by Liu in his thesis. In short, little can be said in comparing the two separate investigations because there does not seem to be any apparent similarity, even though the operating conditions were kept as nearly the same as possible. Figure 1 shows the lack of agreement for the amount of total zinc distilled, expressed as weight percent....

The Effect Of Temper Carbon Nodule Number On The Physical Properties Of A Malleable Iron, William J. Ruprecht

Masters Theses

"It is known that the number of temper carbon nodules per unit volume of malleable iron has an effect on both the rate of anneal and on the resulting physical properties, but neither have been clearly worked out quantitatively. The purpose of this investigation is to ascertain the effect of temper carbon nodule number on certain of the physical properties of a commercial malleable iron.

Quantitative determinations of the effect of temper carbon nodule number would be essential from a theoretical viewpoint in working out the mechanism of graphtization, and would be useful in commercial practice in showing the most …

The Depression Of Quartz In Sulphide Flotation, William Mcminn Billinghurst

Masters Theses

"The flotation of sulphide minerals from siliceous and calcareous gangue minerals always gives a concentrate that is contaminated to a greater or lesser degree with the gangue minerals, even though the collectors used do not show any appreciable collecting properties for the gangue minerals when they are treated alone. In an effort to reduce the amount of undesirable gangue mineral floated with the concentrate it is the practice to add arbitrary amounts of various reagents such as quebracho, alkali hydroxides, carbonates, silicates, sulphides, phosphates, fluorides, and sulphuric acid which have been found to be advantageous. The mechanism of depression is …

The Reactions Of The Sodium-, Potassium-, And The Lithium Tungsten Bronzes In The Solid State, Keki Khodadad Irani

Masters Theses

"The first part of this dissertation has the intention of determining whether MoO₃ forms solid solutions with Na-W bronze corresponding to the formula NaWO_3(1-x) (MoO₃)_x and whether the so-called “sodium-molybdenum bronze” exists.

The next part is concerned with the solubility of K-W bronze in Li-W bronze at high temperatures, in a vacuum, and the last part or this work has the intention of studying the solubility of K-W bronze in Na-W bronze at different temperatures.

The interest in this work is of a purely scientific nature rather than of academic interest"--Introduction, page 1.

A Study Of Volatility And Desulfurization Of Titanium Disulfide, Sheng-Tai Shih

Masters Theses

"The application of high vacuum for the promotion of metallurgical reactions is a comparatively new development. During the war the need for high vacuum in producing magnesium by the Pidgeon Process and in certain phases of uranium purification led to the perfection of both equipment and technique for high vacuum operations. These developments helped open the way for the entirely new field of vacuum metallurgy.

The reduction of metal oxides in vacuum has been studied by Dr. Kroll and Dr. Schlechten. They have been able to reduce many metals from their oxides under reduced pressures using carbon as a reducing …

Investigation To Improve Recovery Of Copper And Gold From A Refractory Ore, Raymond Franklin Cathcart

Masters Theses

"Results of tests presented in this paper indicate that the Santa Maria del Oro ores might be processed by a method which should yield a gold recovery of 96 to 98 percent and a copper recovery of about 78 percent, both figures subject to an increase with further work and study of the problem.

In the method of processing outlined in Figure IX, the ores, mixed as under present operating procedure, would be crushed to minus 20-mesh and roasted with ten pounds of sodium chloride per ton of feed in a multiple-hearth, down-draft roaster at temperatures varying to a maximum …

Precise Lattice Parameter Determinations Of Diamond Silicon And Germanium By The Asymmetric Method, Esrefettin Zeki Aka

Doctoral Dissertations

"The construction of the apparatus for production of powder patterns at a definite temperature and the technique for evaluation of x-ray powder patterns by the asymmetric method are described in detail, and the mode of error elimination is discussed.

A new scanning device is designed for use in x-ray diffraction work.

A modified method is described for the determination of densities of solids, which eliminates some of the difficulties interfering with other similar methods thus far proposed. Formulae are derived for the calculation of density as well as for reduction of density at a desired temperature.

The following conclusion are …

Development, Application And Operating Results Of The Center Peripheral Discharge Rod Mill, David Porter Hale

Professional Degree Theses

"The use of a rod mill for producing manufactured sand is not a recent application. A Marcy Open End Rod Mill has been operating at the plant of the Sun Sand Company, Thayer, West Virginia, since 1925. In early 1940 an 8' x 12' rod mill of the open end type was installed at Shasta. Dam, near Redding, California for sand production. In 1942 work began on Fontana Dam, a Tennessee Valley Authority Project on the Little Tennessee River. The flow sheet included two 9' x 12' high discharge rod mills driven by a single 800 H.P. motor. All of …

The Volatility Of Metallic Sulfides And Their Treatment By Vacuum Metallurgy, Chi-Mei Hsiao

Doctoral Dissertations

"The purpose of this investigation is to determine the vapor pressure or volatility of the sulfides of the following metals by Langmuir's method: a) Zinc b) Cadmium c) Mercury d) Manganese e) Tin f) Lead g) Arsenic h) Antimony i) Molybdenum J) Iron k) Cobalt l) Nickel m) Copper n) Silver o) Calcium p) Aluminum.

The relation of this property to the position of the metals in the periodic table will be discussed, thus the vapor pressure or volatility of the remaining metals can be predicted as to the order of magnitude if the law of periodicity holds.

The possible …

The Nature Of Molecular Films Of Oleic Acid On Quartz, Kenneth Lee Keating

Masters Theses

"The purpose of this research was to show the nature of oleic acid on quartz mineral by transferring calcium oleate films, known to be monomolecular and of a definite orientation, to the surface of a piece of quartz, and measuring the resulting coated mineral by contact angle technique"--Introduction, page 1.

A Study Of Cast Eutectic Structures By Means Of Optical And X-Ray Microscopy, John Stanton Winston

Masters Theses

"The present research is the result of interest in two rather broad, and at first thought, seemingly entirely separate topics: the structure of eutectics and x-ray microscopy. D. Hanson in 1923 in his correspondence with Albert M. Portevin in regard to his article on the structure of eutectics states, "A point that always stuck him (D. Hanson) in examining eutectics was that one of the constituents always formed a continuous phase round the other one. The orientation of one constituent was either constant or varied in a uniform manner. What, however, was the condition of the 'enveloped' constituent, which formed …