Metallurgy Commons^™

Investigation Of Inoculant Effect On Cast Iron, Darrell W. Donis

Masters Theses

"An assumption was made that extensive holding time of an inoculated gray iron melt would result in a loss of physical properties of castings poured from this melt. This theory was examined in both a literature search and by testing and conclusions drawn from these findings are presented and discussed. Although there is a great deal of data available which discusses inoculants and their effects, very little mention is made of the effect of holding time in any of this material. The results indicate that holding time is of considerable importance when dealing with inoculated iron, and that calcium silicon …

Microscopic Observations On Etched Surfaces Of Zinc Single Crystals And On Anodic Disintegration., Yun Wang

Masters Theses

"The technique used to grow single zinc crystals was based on the Bridgman method. Zinc-gold, zinc-aluminum, and zinc-magnesium alloys were prepared and their single crystals were grown. Four crystallographic planes of the single zinc crystals were used for both chemical and anodic etching. The zinc alloys were etched more easily by acids than the purest (99.999%) zinc. The etching patterns changed for the different crystallographic planes of the single zinc crystals.

The appearance of particles during anodic dissolution of the single zinc crystals depended on time, acid concentration and current density. The partial disintegration of single zinc crystals is promoted …

Properties And Perfection Of Zr-H Solid Solutions At Room Temperature., Dirk Heinrich Wiebe

Masters Theses

"The lattice constants of α. - Zr with 122 ppm H are a₂₅ = 3.23622 ± o. 00005 Å and c₂₅ = 5 .1526 ± 0. 0003 Å. The thermal expansion coefficients of α - Zr are found to be α_a =4.6 x 10^-6(⁰C^-1) and α_C =11,0 x 10^-6(⁰C^-1) in the range between 15 and 55°c.

The solid solubility limit in the Zr - H system at room temperature and independent of the H pressure was determined by the parametric x-ray method to be …

A Study Of The Crystallographic Orientation Dependence Of Electrical Resistivity In Zinc, Paul Frederic Becher

Masters Theses

"A potentiometer and galvanometer setup was used to obtain electrical resistivity data for polycrystalline zinc. Cold working textures were investigated by the reflection technique with a quadrant x-ray spectrometer.

Resistivity data were obtained for specimens that were reduced up to forty per cent from the as received condition, and the corresponding textures were studied. The results indicated that the resistivity change in the rolling direction is due to the reorientation of the c-axis in the rolling caused by cold working"--Abstract, page ii.

The Effect Of Cation Size Of Xanthate Collectors In Sulphide Flotation., R. W. Bourne

Masters Theses

"Batch flotation tests on Utah Copper ore were used to show the effect of collector cation size.

The results obtained were:

(1) Recovery of copper in the concentrate decreases with increase in the size of the collector cation.

(2) Increased recovery with ethyl over that for amyl with a given cation.

(3) No beneficial recovery with sulphur enriched xanthates.

Statistical techniques were used to ascertain if significant differences in results were present"--Abstract, p. i

The Effect Of Moisture Content On The Action Of Sea Coal In Molding Sands., Robert J. Endres

Masters Theses

"An assumption was made that an increase in moisture content in the sand would result in an increase in the amount of volatile matter retained in a sand, clay, water, and sea coal mixture which had been subjected to the heat of molten iron. Because of a lack of positive evidence to support this assumption, it was concluded that the volatile matter retained within the sample is independent of the moisture content.

It was also shown that the volatile products do not travel back through the sand, away from the mold-metal interface. Rather, the volatiles escape from the sand and …

The Imperfect Structure Of Ti-, Zr-, And Hf- Nitrides Containing An Excess Of Nitrogen., Chester A. Faunce

Masters Theses

"Chemical analyses were made on all three nitrides using oxidation, Kjeldahl, dissolution and gas evolution techniques, and the chemical formulae were calculated. They are as follows: Ti_0•931^N, Zr_0•970^N, and Hf_0•792^N.

The lattice constant of all the nitride samples was determined at 25°C. The Ti_0•931^N sample obtained from Union Carbide Company had a lattice parameter of 4.23986± 0.00007A⁰, while the sample from W. Germany, Ti_1.0^N in the as received condition had a lattice parameter of 4.24027 t 0.00003A⁰• A second lattice parameter determination was …

Sonic Flow Meter., Daniel E. Wilson

Masters Theses

"The purpose of this thesis was to construct a device to measure the velocity of air employing sound waves. The principle of operation of the device is that the time interval required for the sound wave to travel between two points in the duct is a function of the fluid velocity. This time interval was measured both with the air flowing and with the air stationary. An equation was derived such that the mean velocity of the flowing air could be calculated by knowing the two-time intervals.

The mean velocity determined by this device was compared to the mean velocity …

Anodic Dissolution And Disintegration Of Indium, Thallium, And Indium-Cadmium Solid Solutions And Valency Of The Ions Going Into Solution., Richard Lloyd Martin

Masters Theses

"Indium was found to form only In⁺³ ions when dissolving anodically in aqueous acid solutions. Thallium dissolves anodically in acid solutions giving Tl⁺¹ ions only. The reason why Faraday's law is not being formed is that the anode undergoes partial disintegration producing small metallic particles.

Disintegration of these anodes depends on several factors: the nature and concentration of the corrosive medium, the surface condition of the anode, the current density, and the temperature of the corrosive solution. Disintegration may be due to different mechanisms depending on the nature of the electrolyte" -- Abstract, p. ii

The Anodic Dissolution And Disintegration Of Gallium And Aluminum And The Initial Valency Of The Ions Entering Aqueous Solutions., Kenneth Anderson Poush

Masters Theses

Gallium dissolved very slowly in dilute acids like HC1, H₂SO₄and HCIO₄. The rate was substantially accelerated if the metal was connected with a platinum electrode in the same solution. From the volume of the hydrogen developed the trivalency of gallium ions going into solution was calculated. This same ionic charge was obtained from coulometric measurements using gallium-amalgam as the anode. The initial ionic charge of aluminum dissolving from an aluminum amalgam anode was evidenced as being plus three by coulometric measurements.

Gallium and aluminum anodes were found to partially disintegrate while the current flowed. …

Study Of The Temperature Dependence Of The Haeffner Effect In Mercury, Charles George Arnold

Masters Theses

“In 1953, E. Haeffner (1) reported that after he had passed a direct electric current through a capillary tube filled with mercury, he obtained a separation of the isotopes of mercury. It was found that the heavier isotopes were enriched at the negative terminal and the lighter Isotopes at the positive terminal. This effect has since been referred to as the Haeffner Effect. Since this original experiment, other investigators have observed this effect in many other liquid and some solid metal systems.

The work of J. N. Baysden (2) showed that the separation of the isotopes in mercury could be …

A Thermodynamic Study Of The Zirconium-Sulfur, Titanium-Sulfur And Hafnium-Sulfur Systems In The Disulfide-Trisulfide Region, Norbert Achilles Vermaut

Doctoral Dissertations

"A static method was used to study the equilibria which exist between the higher sulfides of zirconium and sulfur at temperatures from 700° to 1000 °C. Both disulfide and trisulfide have been identified by chemical analysis and X-ray diffraction. There exists a two-phase region of 'ZrS₂' and 'ZrS₃'. The composition limit of the homogeneous disulfide phase appears to exist between ZrS_1.90 and ZrS_2.00. The lower composition limit of the homogeneous region of the trisulfide phase was established as ZrS_2.75.

An experimental method of Blitz and co-workers, i.e., the use of evacuated …

Lattice Parameters, Thermal Expansion Coefficients, Densities, And Imperfections In Silver And In The Alpha-Phase Of The Silver-Indium System, Samir Moustafa Riad

Doctoral Dissertations

“An investigation of structure insensitive properties (lattice parameters, thermal expansion coefficients, densities, and imperfections) of silver and the α-phase of the silver-indium system was suggested by the desirable uses for silver and its indium alloys.

Both silver and indium used were 99.999 per cent pure. The silver-indium alloys were prepared by melting both metals inside evacuated and sealed fused quartz tubes. The solidified alloys were annealed and then examined by X-ray diffraction for homogeneity.

This experimental work is divided into three main parts:-

I. X-ray diffraction investigation to determine the solid solubility limit of the Ag-In α-phase at 25° C, …

Studies In Modulation Of Interfacial Reactions For Certain Sulphide Minerals, Robert Owen Beyaert

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Habit Modification Of Naclo3 With Nai, William A. Coghlan

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Production Of Standard-Grade Ferromanganese In An Electric Arc Furnace, Force F. Baney Jr.

Bachelors Theses and Reports, 1928 - 1970

The investigations conducted in this project were essentially concerned with the effects of various compositions of two different slag systems upon the increased recovery of manganese in a standard-grade ferromanganese.

Investigation Of The Ternary System Silver-Aluminum-Indium (Ag-Al-In), Elvin H. Beardslee

Bachelors Theses and Reports, 1928 - 1970

This thesis paper contains material pertaining to & preliminary investigation of the ternary system Ag-Al-In. Procedures in this preliminary investigation are discussed in detail.

Preliminary Examination Of The Aluminum Corner Of The Ternary System Aluminum-Silver-Indium (A1-Ag-In), Jerome J. Blake

Bachelors Theses and Reports, 1928 - 1970

In this paper the author attempts to lay the groundwork for future work on the Al-Ag-In system.

Increased Corrosion Of A 304 Stainless Steel Upon Bending, William C. Tiddy

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Identification Of Nonmetallic Inclusions In Armco Ingot Iron With Polarized Light, Frank E. Panisko

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

The Hydrometallurgy Of Uranium, John E. Cesarani

Bachelors Theses and Reports, 1928 - 1970

No abstract provided.

Liquid Mercury Embrittlement Of Thin-Walled 2024 Aluminum Tubes, Edward J. Beckemeyer

Masters Theses

"The dislocation theory, Zener-Stroh crack model, and the Petch relationship, which correlates fracture stress and grain size, were used to analyze the embrittlement of 2024 aluminum alloy tubes by liquid mercury.

Surface energy ratios, [formula], were determined for biaxial stress ratios of 1/2, 1, ∞. The values of the surface energy ratios considered were 4.24, 1.79, 1.46, respectively. As part of this study, an approximate Nabarro-Peierls frictional stress was calculated for each stress ratio"--Abstract, page 2.

A Dilatometric Study Of The Martensite Transformation And Maraging Behavior Of A Ni- Co- Mo Steel, Neal Matthias Griesenauer

Masters Theses

"An experimental investigation or the austenite to martensite transformation and the maraging behavior taking place in a nickel-cobalt-molybdenum steel was conducted for this project.

The austenite to martensite transformation was followed by the dilatometric method, being done on a Leitz Optical Dilatometer. An apparatus was constructed for the dilatometer in order to record dimensional changes at low temperatures, thus broadening the possible applications for the instrument.

The maraging behavior was investigated by means of metallographic analysis and hardness determinations"--Abstract, page i.

Phase Extent Of Gaas, Gasb, And Insb, And Solid Solubility In The System Gaas-Gasb Determined By The Lattice Constant-Density Method., Chang Don Kim

Masters Theses

"The lattice constant of the homogeneous gallium arsenide varies from 5.65298A⁰ to 5.65J26A⁰ at 25° c with a change of composition in the range from 49-935 to 50.015 atomic percent gallium. The lattice constants of g allium and indium antimonide are 6.09592A⁰ and 6.47876A⁰ at 25 ° c, respectively and the extent of the phases of gallium and indium antimonide could not be found in this work.

The thermal expansion coefficient of gallium arsenide is 6.4 x 10^-6/⁰ C in the range between 10 and 65° c regardless of composition, ar.d those of …

A Study Of A Method For Determining Properties Of Metals At High Strain Rates., Warren Heidbreder

Masters Theses

"An experimental method has been developed for determining the tensile and other physical properties of metals under high loading rates. Experimental equipment was designed, fabricated and tested. It was desirable to keep the equipment simple and inexpensive so that it could be used by operators Lacking experience in electronics and high-speed photography which are required for some of the more sophisticated methods now in use. The energy for pulling the specimens is supplied by smokeless gun powder. The firing of a cartridge into a closed cylinder with movable piston accomplishes the breaking of the specimen. A record of the time, …

Non-Ferrous Metal Mining And Smelting In Australia, H. R. Hanley

Missouri School of Mines and Metallurgy Bulletins

No abstract provided.

Zinc Sulfide-Sulfate Reaction Pressures, William L. Hallerberg

Masters Theses

"A static manometric method was used to find the equilibrium reaction pressure as a function of temperature for the reaction:

11 ZnSO₄ + ZnS → 4 (ZnO·2ZnSO₄) + 4 SO₂

From the reaction pressures, the standard free energy of the reaction was found to be:

ΔF⁰ = + 51,320 - 36.68 T

Using thermodynamic data for ZnSO₄, ZnS and SO₂ the standard free energy of formation of the basic salt ZnO·2ZnSO₄ was found to be:

ΔF⁰ = - 377,000 - 65.9 T cal/mole

in the temperature range 350 to 420⁰ C.

Above …

Dissolution Rates Of Zone Refined Iron And Steel In Hydrochloric And Sulfuric Acids And In Sodium Chloride Solutions., Gary E. Welch

Masters Theses

"Dissolution rates for two carbon steels were deter­ mined in four concentrations of sulfuric acid at five temperatures and in four concentrations of hydrochloric acid at four temperatures.

No general relationship was found for the variation in activation energies in sulfuric and hydrochloric acid. An explanation of the difference in the reaction rates and a possible explanation of the activation energy is presented on the basis of chunk formation.

The results of this investigation indicate an electrochemical control mechanism for the dissolution reaction of steel in acid solutions.

Results of dissolution rate studies in sulfuric and hydrochloric acid solutions and …

A Thermodynamic Study Of The Molybdenum-Sulfur System At 1100⁰C, Seth C. Schaefer

Masters Theses

"A static method was used to determine equilibrium sulfur pressure for molybdenum-sulfur mixtures at 1100°C.

The results obtained were:
(1) The molybdenum disulfide phase was stable in a sulfur pressure range of 1.023 x 10^-5 to 6.026 x 10^-1 atmospheres. A range of non-stoichiometry from MoS_2.00 to MoS_2.22 was determined under these conditions.
(2) The upper limit of sulfur content of molybdenum sesquisulfide (Mo₂S₃) is nearly stoichiometric.
(3) The extent of solid solution of sulfur in molybdenum is approximately 1.5 atomic % (0.5 wt %).
(4) Molybdenum sesqu-isulfide (Mo₂S_{3 …}

A Study Of The Solubility Of Gold In Aluminum And The Extent Of The Al₂Au Phase., Kuldip Singh Chopra

Masters Theses

"The lattice constant of pure aluminum (99.998%) at 25° C 0 was determined to be 4.04953 A and the limit of solubility of gold in aluminum at 58O° c was found to be about o.4 weight percent gold. The minimum of the lattice constant was observed at O.75 weight percent gold. No change in the lattice constant with time was found.

The Al₂Au phase has a range from 77.66 to 78.94 weight percent gold with the theoretical composition of Al₂Au nearly in the middle of the phase. The thermal coefficient of expansion, the density and the …