Metallurgy Commons^™

The Effects Of Sulphur And Copper On Hot-Workability Of Pure Iron, Hung-Chi Chao

Masters Theses

"The independent effects of sulphur, copper and their combinations on the hot-workability of pure iron free from other elements was studied, with special emphasis on the red-short phenomenon. Electrolytic pure iron with the addition of 0.023 cent sulphur, 0.33 per cent copper and 0.024 per cent sulphur plus 0.032 per cent copper along with a heat of only electrolytic pure iron was melted under vacuum, and cast under helium pressure. The specimens machined from the forged bars were tested at various temperatures by the hot twist-test and by the constant energy single blow drop forging test to evaluate the hot-workability …

A Dissolution Rate Study Of Beryllium In Hydrofluoric Acid, Donald Lee Mathis

Masters Theses

"Beryllium was shown to react stoichiometrically with HF, HCl, and H₂SO₄ acids in accordance with a plus two valence. These reactions were investigated by the hydrogen evolution method.

Dissolution rates were determined in five concentrations, 0.01, 0.05, 0.10, 0.50, and 0,75 N, of HF acid at 10, 20, 30, 40 and 50°C, This was accomplished by the hydrogen evolution method and the results were based on the tested stoichiometry. Beryllium has a high dissolution rate in HF acid, which approximates the following under similar conditions: 10 times Al, 4 times Ti, and 1.5 times Zr. A kinetic …

Copper Converter: Basic Research Testing With A Plastic Model Converter And Four Types Of Refractories, Arthur C. Bigley Jr.

Bachelors Theses and Reports, 1928 - 1970

In recent years there has appeared an increasing number of papers on converting operations as related to thermodynamics. This approach is a powerful, potential tool. However, the development of new ideas and changes must rely on accurate basic information.

Microradiography Of Metals And Alloys Using A Medical X-Ray Unit, W. R. Byrne

Bachelors Theses and Reports, 1928 - 1970

There is no doubt that the microradiograph technique is of value to the metallurgist. A three-dimensional picture to supplement the photomicrographs should give a true picture of the microstructure. Microradiography can be used where etchants can not differentiate between the various components or where no etchant can be found suitable for a particular alloy.

Comminution Studies, George A. Grandy

Bachelors Theses and Reports, 1928 - 1970

Comminution, reduction in size, is one of the most important, yet least understood, steps in mineral dressing. So that more efficient comminuting devices may be designed and constructed, a better knowledge of the relationship between energy consumption and size reduction is desired. Occasional studies during the last 100 years have produced a few "laws" purporting to describe this relationship. In each case, the promulgators and supporters of these laws have presented experimental evidence for their verification. Obviously, all of these advocated practices cannot be correct. To the mill designer, the problem is "Which, if any, of these laws are valid." …

Secondary Recrystallization In Copper, James E. Thompson

Bachelors Theses and Reports, 1928 - 1970

The purpose of this thesis is to study the conditions under which secondary recrystallization will take place in copper. The variables considered were the time annealing, the temperature of annealing, and the degree of cold work undergone by the specimen before it was subjected to the heat treatment.

Growth Of A Preferentially Oriented Aluminum Single Crystal, John George Bjeletich

Bachelors Theses and Reports, 1928 - 1970

When studying some anisotropic property of a specific metal, such as the critical shear stress of aluminum, it is desirable that the test specimen be a single crystal with the crystal axes preferentially oriented. Therefore, it is necessary to obtain a single crystal by one of the methods mentioned and by use of x-rays to determine the orientation. Once the single crystal is obtained and the orientation known, it is possible to grow a preferentially oriented aluminum single crystal by a method generally known as "seeding". The purpose of this thesis problem was to grow a crystal by utilizing the …

The Identification Of Montana Clays By X-Ray Analysis, James Francis Donovan

Bachelors Theses and Reports, 1928 - 1970

This investigation is concerned primarily with the determination of the various clay minerals comprising certain deposits through the state. This investigation was accomplished with the use of X-Ray diffraction equipment and it can be easily understood why this equipment has been of such benefit to the clay mineralogist.

The Macromosaic Structure Of Lead Single Crystals, Eldon J. Nicholson

Bachelors Theses and Reports, 1928 - 1970

The purpose of this investigation is to examine this structure [macromosaic] to determine any properties or characteristics peculiar to it that could shed light on its cause or on the basic mechanism of crystal growth from the melt.

Autoclave Leaching Of Montana Chromite, Leonard S. Greely

Bachelors Theses and Reports, 1928 - 1970

The purpose of this investigation was to determine the feasibility of caustic autoclaving of Montana chromite in order to recover the chromium in a relatively pure solution of sodium chromate.

Imperfections In A Silicon Crystal Studied By The X-Ray And Density Method, Pierre Borgeaud

Masters Theses

"The study of imperfections in several crystals of silicon was conducted by the x-ray and density method"--Abstract, page 2.

A Thermodynamic Study Of The Germanium Sulphides, Satya Prakash Jain

Masters Theses

"The experimental determination of some of the thermodynamic properties of germanium sulphide phases was conducted by a hydrogen reduction technique. The equilibrium H₂S/H₂ ratios were determined as a function of temperature for the two phase equilibria GeS₂-GeS and GeS-Ge. A Tutwiler analysis technique was used to analyze the equilibrated gas mixture for hydrogen sulphide content.

A detailed description is given for the process and the apparatus used in performing the experiments for equilibration of H₂S/H₂ gas mixture. The methods used for the preparation of germanium sulphide phases are also discussed.

The investigation …

A Thermodynamic Study Of Germanium Sulfides, Sham Lal Malhotra

Masters Theses

"The vapour pressure of germanium monosulfide (liquid) was determined by a boiling point method. An expression for the vapour pressure as a function of temperature was obtained and the heat of vapourization calculated. Using the heat of sublimation data obtained by other investigators, the heat of fusion was calculated.

The thermodynamic properties, change of standard free energy (Δ F°) heat content (Δ H°) and entropy (Δ S°); of germanium disulfide were determined by using an indirect method. The equilibrium H₂S/H₂O ratios are determined for the reaction:

GeS₂ (s) + 2H₂O(g) = GeO_{2 …}

High Temperature Oxidation Of Nickel, Virgil R. Friebel

Masters Theses

"Using a sensitive volumetric technique, a study was made of the kinetics of oxidation of nickel at 1200° C. and 1300° C. Three purities of nickel were used for the investigation which was limited to the initial three hours of reaction.

The rate of oxidation of nickel followed the parabolic rate law after an initial period of deviation which lasted up to 40 minutes. No direct correlation was found between the oxide thickness and the end of the period of deviation from the parabolic rate law.

The purity of the nickel was found to have a marked effect on the …

The Constitution Of Magnesium-Rich Magnesium-Zirconium Alloys, Kenneth Allen Fowler

Masters Theses

"The magnesium-zirconium system has been studied to 0.8 per cent zirconium which represents the limit of solubility of zirconium in liquid magnesium at 950°C. Alloys have been prepared by two methods of alloy additions, and the results compared. Microstructural studies have been made of the alloys in the cast, extruded, and heat-treated conditions. The limit of solid solubility has been determined on the basis of resistivity and temperature coefficient of resistivity measurements, as well as by metallographic examination, with good agreement. A secondary structure resulting from precipitation of a second phase within cored regions of the alloy has been studied …

The Effect Of The Rare Earth Elements On The Hot Workability Of Ingot Iron, L. A. Neumeier

Masters Theses

"The effect of mischmetal and rare earth oxides on the hot workability of ingot iron in the hot-short region was studied. Thirteen heats were melted in air in a basic-lined induction furnace. All heats were thoroughly deoxidized with aluminum prior to the rare earth additions. Mischmetal was added in amounts of 0.1, 0.3 and 0.5 per cent. Rare earth oxides were added in amounts of 0.1 and 0.2 per cent. Temperatures were maintained at approximately 2900°F and holding intervals between mischmetal additions and pouring at two minutes. Bars were hot rolled and swaged for hot twisting in the hot-short region. …

Segregation Method As Possible Process To Beneficiate Oxidized Lead Ores, Jose Molfino Tomasio

Masters Theses

"In this investigation it has been demonstrated that the Segregation Process has merit for treating oxidized lead ores.

The process comprises heating the crushed ore with salt and coal at about 750° C. to produce metallic lead attached to the carbon particles, which then is recovered by conventional flotation methods.

The quantities of sodium chloride and coal required for the best segregation of lead obtained in this work was 1.0 percent of coal and 1.0 percent of salt by weight.

Good segregation was obtained by using salt and coal as fine as 65 or 48 mesh. Segregation varied with the …

A Thermodynamic Study Of The System Pbo-Pbs, John P. Hager

Masters Theses

"An experimental investigation was conducted in order to determine the thermodynamic and kinetic behavior of the system PbO-PbS.

The thermodynamic behavior of the system PbO-PbS was studied by measuring the P_SO₂ in argon-SO₂ mixtures equilibrated with various PbO-PbS mixtures in a recirculating-type equilibrium apparatus, and analyzing the condensed phases by means of X-ray diffraction.

The effect of temperature and PbO/PbS ratio on the rate of SO₂ evolution was investigated in order to determine the reaction mechanisms involved in the approach to equilibrium.

A sodium hydroxide, hydrogen peroxide titration technique was employed in the analysis of SO_{2 …}

Preparation Of Casting Slips Containing Ferrous Powders And Alginates, Robert Eugene Newcomer

Masters Theses

"The preparation of casting slips containing ferrous powders dispersed by alginates was studied and an attempt was made to determine the mechanism by which suspension was attained. The colloidal aspects of preparing ceramic casting slips are discussed and an analogy is drawn to preparation of metallic slips suspended by alginates.

Sodium and ammonium alginates were used to suspend stainless steel and iron powders. The effect of NaOH, HC1, and various phosphate additions on the properties of slips and algin solutions was considered.

It was found that colloidal concepts can not be applied to explain observed behavior in the system studied. …

A Dissolution Rate Study In Hydrofluoric Acid Of Titanium And The Alpha Solid Solutions Of Oxygen In Titanium, John L. Ratliff

Masters Theses

"The dissolution mechanism of titanium in hydrofluoric acid was studied by collecting the hydrogen evolved during the dissolution reaction. A concentration range of 0.05 N to 0.50 N and a temperature range of 15°C to 45°C were employed for the determination. Values of the reaction order and energy of activation were determined for both pure titanium and the alpha solid solutions of oxygen in titanium and found to be the same within experimental limits. This indicated that the reaction giving rise to hydrogen evolution on the surfaces of both pure titanium and the TiO_x alloys was the same. The …

Identification Of Inclusions In Armco Ingot Iron By The Use Of Polarized Light, Carl A. Plate

Bachelors Theses and Reports, 1928 - 1970

It is the author's hope that by systematically investigating the inclusions in ingot iron and comparing their specific properties with the properties of substances known to exist as inclusions, a rapid and accurate method may be found to identify them using a polarizing microscope. Where possible photomicrographs will be used to illustrate the results obtained so that the reader may obtain a better picture of the effects produced by polarized light.

An Investigation Of The Fundamental Factors Affecting The Green Ball Characteristics In Pellet Formation, Thomas J. Wright

Bachelors Theses and Reports, 1928 - 1970

The purpose of this investigation is to determine the relative effects on the quality and characteristics of the pellets. Once the major factors effecting agglomerating materials are understood, formerly poor and nonagglomerating materials may be affected so that they will produce good quality agglomerates. Should the factors prove difficult to vary or impossible at least they may be identified and understood, thus serving as a guide for further attack or judgment in overall process design.

An Investigation Of The Effectiveness Of Certain Organic Compounds In The Flotation Of Manganese Oxide Minerals, Johannes P. Dreyer

Bachelors Theses and Reports, 1928 - 1970

This thesis has to do with the selective flotation of the manganese oxide minerals in an ore from Charco Redondo Mine, Oriente Province, Cuba. Since a sound knowledge of the nature of the emulsion-induced flotation process of these minerals does not exist, experimental research constitutes the most valuable resource for determining the extent to which different reagents influence the process. Moreover, a correlation of experimental results with the chemical and physical properties of the minerals and reagents can lead to the improvement of existing theories regarding the mechanism of a process.

Separation And Concentration Of Stibiconite, William Howard Painter

Bachelors Theses and Reports, 1928 - 1970

Primarily, the purpose of this study is to separate stibiconite from associated gangue minerals. The ore containing antimony, as an oxide stibiconite, occurs in Mexico and its benefication would be an advantage to the mineral resources of that country. While the deposit from which this ore is derived is American owned, the resource is presently non-economic. A concentrate must be derived of suitable grade for its use in a smelting operation and from which metallic antimony would be produced.

Streaming Potential Studies On Rutile, Albert R. Rule

Bachelors Theses and Reports, 1928 - 1970

This investigation was undertaken to determine some of the electrokinetic properties exhibited by rutile in solutions of various electrolytes. Results presented in this thesis are for rutile in solutions of conductivity water and in potassium chloride solutions. The data obtained in this investigation are presented graphically in the body of the thesis and are tabulated in the appendix for convenience.

Electrical Methods Of Mineral Concentration, Gordon F. Ziesing

Bachelors Theses and Reports, 1928 - 1970

The evaluation of a mineral-dressing method cannot be carried out successfully without an initial understanding of the basic fundamentals and concepts governing the operation of the method. Experimentation, governed by the understanding of the basic concepts, together with intelligent conclusions based on the experimental data, complete the evaluation of the dressing method.

Electrical concentration, being the given dressing method, will be evaluated as discussed above. As they are thoroughly covered by Mora (13), the fundamental concepts will not be given a lengthy discussion.

Electric Arc Furnace Production Of Standard-Grade Ferromanganese, Curtis Bates

Bachelors Theses and Reports, 1928 - 1970

The purpose of this investigation is to determine an operating procedure for electric arc furnace production of standard ferromanganese. An attempt was made to determine a charge which would give steady power consumption in the furnace and at the same time keep the manganese content in the slag to a minimum.

Stress-Induced Martensite Transformation In An Alloy Of The Copper-Aluminum-Nickel System, Gary D. Alexander

Bachelors Theses and Reports, 1928 - 1970

It was intended that the alloy be thoroughly investigated for martensite transformation that would make the alloy "super-elastic," but due to the many difficulties that arose this was not possible. Attempts to grow a single crystal from the cast alloy were not successful because of the difficulties that were encountered with the Kanthal resistance furnace (referred to later). Consequently, the growing of the single crystal was abandoned and the alloy was tested in the poly-crystalline form.

Growth And Examination Of Calcium Single Crystals, Richard W. Roberts

Bachelors Theses and Reports, 1928 - 1970

This report is in two sections. The first section relates to a vacuum technique for growing single crystals of calcium. The second section discusses the results of an X-ray examination of crystals of zinc by the back reflection Laue method.

The Identification Of Montana Clays By X-Ray Analysis, George Mason Maxwell

Bachelors Theses and Reports, 1928 - 1970

This thesis is to be written with the assumption that the reader is familiar with the more elementary facts of X-ray crystal analysis, such as the production and properties of X-rays, and the Bragg reflection law.

The purpose of this paper is to report on the investigations carried on to find some relatively simple means of identifying Montana Clays.