Metallurgy Commons^™

Assessment Of The Accuracy Of Metal Cutting In A Microcomputer Controlled Machine, Aly Mohamed Saad Ed-Din Dars

Archived Theses and Dissertations

No abstract provided.

Solid Solubility Of Sulfur In Transition Metal Oxides And Stability Of Sulfates Relevant To Roasting Processes, Zeynal Karakus

Masters Theses

"Two types of sulfur equilibration experiments were carried out in this study using either a conventional thermal gravimetric analysis (TGA) technique or a horizontal tube furnace apparatus. Samples were equilibrated with flowing SO₂-O₂ gas mixtures of either 58% SO₂ or 10% SO₂.

The types of experiments were:
1. Investigation of the extent of solid solution of sulfur in ZnO, NiO, CuO, and Fe₂O₃ over a wide range of temperature.
2. Studies of compound or solid solution formation between binary sulfate mixtures of Fe-Zn, Cu-Zn, Ni-Zn, Fe-Cr, and Cd-Zn by TGA.

The …

Ion Implantation For Improvement Of Wear Properties Of Steels, Kenneth W. Burris

Masters Theses

"Previous research on ion implantation at U.M.R. has dealt with the development of a modified Falex Lubricant Tester as a valid wear test and its use in dose curve determination. Our recent work uses Auger surface analysis and scanning electron microscopy to gather support for a model that will tie together some of the many theories proposed as to why ion-implantation improves the surface related mechanical properties of steels"--Abstract, page ii.

Dynamics Of Twinning In Natural Α-Quartz, Alexander Aning, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

Finite amplitude internal friction experiments in α-quartz are described and interpreted in terms of the theory of nonlinear anelasticity. The theory predicts a linear relationship between the driving force of the excitation and the period of the auto modulation at its onset. This relation is substantiated by experiments performed with a natural α-quartz reed vibrating in flexure at resonance frequencies between 65 and 170 Hz in the temperature range of 162° and 224°C. The data suggests that Dauphiné twinning in α-quartz causes the auto modulation governed by an activation energy of 92 kJ mole. This activation energy characterizes short distance …

Dynamics Of Stress Induced Hydride Formation In Vanadium, Alex Aning, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Non-Linear Oscillation, Automodulation And Anelasticity, Tetsuro Suzuki, Manfred Wuttig

Physics Faculty Research & Creative Works

The auto modulation observed in the course of internal friction is discussed as a special example of the universal nature of non-linear oscillations. Universal features of non-linear oscillations are the requirement of energy supply or negative damping and the period doubling route to chaos. The negative damping responsible for the auto modulation is described in terms of the soliton model for twinning deformation. © 1984 The Japan Society of Applied Physics.

Electrogalvanizing And Drawing Of Steel Wires, Thomas Joseph O'Keefe Jr.

Masters Theses

"The effects of varying current density, temperature, Zn⁺² and licorice concentrations on the morphology of the zinc deposited on steel wire have been studied and compared. The plated wires were then drawn and evaluated in terms of required drawing energy and zinc loss during processing of up to 40% reduction in area. Scanning electron microscope and X-ray diffraction were used to evaluate the electrodeposits"--Abstract, page ii.

The Role Of Boron In So32 And So43 Steels, Sunil S. Moghe

Masters Theses

"In this project study was conducted with the goal of understanding the role of boron involved in structure-toughness property relationship for SO32 and SO43 steels. For a standard heat-treatment of austenitizing (1 hr.) at 1700°F, water quenching and 1 hr. tempering at 1150°F SO32 steel (with 37 ppm B) lacked in toughness, while SO43 steel (with 2 ppm B) showed good toughness. In both steels all the boron was present in the form of "soluble boron" i.e., Fe₂₃ (B,C)₆ borocarbide. Experiments were carried out to study the effect of various heat treatment parameters on the precipitation behavior of …

The Effects Of Certain Impurities And Their Interactions On Zinc Electrowinning, Donald R. Fosnacht, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

The effects of germanium, antimony, arsenic, cobalt, glue, and free acid concentration were studied on both commercial and synthetic electrolytes. The effects of a single factor and the combined effects of multiple factors were elucidated. The temperature, zinc concentration, and current density were varied for some of the tests. It was found that the acid content was the most critical factor when impurity levels were at normal plant solution concentrations. The ranges where the effect of the impurity became apparent were: greater than 20 ppb (parts per billion) for antimony; 40 ppb for germanium; 120 ppb for arsenic; and 7 …

Screening Design Test For Cobalt Cementation From Zinc Electrolyte, Mark S. Blaser, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Fuel And Process Efficiency's Affect On The Selection Of Surface Heat-Treating Processes, Christopher Scott Thorman

Graduate Research Papers

Ever since the advent of the Industrial Revolution part components and tooling have required production heat-treating to maximize life. Various forms of heat-treatment are available to heat-treating technologists and engineers, all of which have their advantages. To maximize investment, managers must decide between new processes to gain efficiency and the updating of current process to improve efficiency. Cost considerations are important but not the only ones. Quality and safety are also important to remember.

Production capacity, both present and future, is also related to cost effectiveness of heat-treating process. The heat-up and cool-down aspect which is a vital characteristic to …

Comments On A Paper By Baik And Raj, Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Twinning Pseudoelasticity In Intl, Manfred Wuttig, Lin Chun-Hung

Materials Science and Engineering Faculty Research & Creative Works

Twin boundaries generally contribute significantly to the damping of a twinned crystal. In an In-19.1 at.% Tl single crystal the damping gives rise to auto modulation if the internal friction studies are performed in the 10 Hz frequency range, with a strain amplitude larger than 0.05 and at temperatures lower than 10°C. The frequency of the auto modulation is about 60 times slower than the frequency with which the reed type sample is driven. The auto modulation frequency has a maximum at -6 C and is characterized by an activation energy of 29 kJ/mol (7 kcal/mol). This maximum can be …

The Influence Of Additives And Their Interactions On Copper Electrorefining, Chwan-Tsann Wang

Doctoral Dissertations

"Protein colloid (glue), thiourea, Avitone and chloride ion are the most common additives used electrorefining copper. The polarization behavior of these additives, single and combined, was studied by cyclic voltammetry techniques in conjunction with stationary and rotating disc electrodes. In the stationary electrode work, different protein colloids give substantially different results in polarization or interaction with other additives. The role played by Avitone is not clear, but it does somewhat modify other additives in the electrolyte. Thiourea can cause a depolarized peak and a polarized plateau depending on the concentration, the other additives present and the potential selected. Chloride ion …

The Effect Of Selected Alloying Elements On The Hardness And Microstructure Of Ductile Cast Iron, Chi-Hua Edward Tseng

Masters Theses

The effects of cooling rate and alloying element on the matrix structure, nodule count and hardness have been studied in this investigation.

Recommendations for producing ferritic ductile iron have been made and the relationship between hardness and pearlite percentage has been obtained in this study.

Separation Of Mineral Particles In Cyclones Under The Influence Of A Magnetic Field, Kwasi Amoako-Gyampah

Masters Theses

"The separation of mineral particles in a cyclone under the influence of a magnetic field was investigated using an electromagnetic - cyclone arrangement. Feed pulps of dolomite and magnetite were used in the study. Two different cyclone types were investigated: An air-type cyclone arrangement and a conventional cyclone arrangement. Magnetic field strengths of 0 to 3000 gauss (0 - 0.3 Tesla) were used in the study by varying the current through the coils of the electromagnet .

The parameters evaluated in the study were the grades and recoveries of the magnetic concentrates produced, the enrichment ratios, the improvement in recoveries …

Nonlinear Anelasticity Of Magnesium, Alexander Aning, Tetsuro Suzuki, Manfred Wuttig

Physics Faculty Research & Creative Works

An approximate solution of the equation of motion of a nonlinear anelastic reed at or near resonance is presented. The steady state solution reproduces the well-known nonlinear resonances. The solution also predicts the existence of auto modulations, i.e., self-excited modulations of the amplitude and phase at constant power of excitation of the reed. Numerical examples of such auto modulations are presented for an antisymmetric deformation potential. Experimental studies of finite amplitude oscillations of a magnesium reed vibrating at 72 and 431 Hz at room temperature confirm the existence of auto modulations. The experimental results can be semi quantitatively described in …

Desirable Combinations Of Electrode And Flux For Submerged Arc Welding Of Low Carbon Steel, James A. Husmann

Graduate Research Papers

The major purpose of this study was to provide information about desirable combinations of welding electrode and appropriate fluxes for submerged arc welding of low carbon steel. Other purposes were to:

1. Test a variety of combinations of available submerged arc welding electrodes and fluxes in welding low carbon steel.

a. Prepare specimens for tensile tests.

b. Conduct tensile tests.

c. Calculate tensile strength, yield point, break point, percent of elongation, and percent reduction of area.

2. Determine the most desirable combinations of electrode and flux for companies presently using or planning to use submerged arc welding for low carbon …

Phaseautomodulation In Magnesium, Alexander Aning, Tetsuro Suzuki, Manfred Wuttig

Physics Faculty Research & Creative Works

No abstract provided.

Anomalous Diffusion Of Carbon In A 70/30 Iron-Nickel Alloy, L. R. Chapman, D. A. Powers, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Drawing Characteristics Of Electrogalvanized Steel Wires., Chi-Yuan Tsao

Masters Theses

"As a means of investigating the often adverse drawing behavior of electrogalvanized steel wire, drawing experiments were conducted on a variety of industrially-supplied and laboratory-prepared electroplated steel wires. Back-flow and shaving appeared to be the mechanisms by which sizeable zinc losses occurred. Performance during drawing and the quality of the product depended upon both the characteristics of the plating and the drawing process variables. Grain size, grain texture, and surface 'flatness' can affect the required drawing force, surface finish and level of zinc retention. Low die angles and large reductions offered greatest efficiencies with minimum zinc loss"--Abstract p. ii

Computerized Twist Drill Selection For Cast Iron And Steel, Clinton K. Orth

Graduate Research Papers

The science of hole making can hardly be considered new to modern day industry. Evidence of drilling dates back as early as 4000 B.C. However, computers are considered relatively new to industry and their use is growing rapidly. One of the major concerns of industry is to identify a consistent method of selecting the proper drill when given a set of variables. The problem is to identify the sets of variables and select a drill that will give consistent results.

Model For Evaporation Of A Grain‐Boundary Phase, Manfred Wuttig, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The surface profile which develops in the vicinity of a grain boundary precipitate in the course of evaporation is calculated. It is shown that the presence of the grain boundary precipitate affects the profile significantly if the product of the width of the grain boundary precipitate and the ratio of the evaporation rates of the unperturbed surface and the grain boundary precipitate is larger than one. Copyright © 1981, Wiley Blackwell. All rights reserved

Plastic Deformation And Fracture Of Two-Phase Alloys Under Compressive Loading, Abla Mahmoud Zayed

Archived Theses and Dissertations

No abstract provided.

Autooscillations In Zinc, Manfred Wuttig, Alex Aning, Tetsuro Suzuki

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

The Inert Gas Effect On The Rate Of Evaporation Of Zinc And Cadmium, P. C.S. Wu, Thomas J. O'Keefe, Fred Kisslinger

Materials Science and Engineering Faculty Research & Creative Works

An experimental study has been made to investigate the effect of argon and helium on the rate of evaporation of zinc and cadmium under one atmosphere pressure at temperatures ranging from 500 to 850°C. The experimental results were compared with the maximum rates calculated using the effusion formula as well as with values obtained using two different types of equations based on kinetic theory, diffusion theory, and empirical data. Equations have been derived for expressing the rate of evaporation of zinc and cadmium in both argon and helium as functions of temperature of the liquid zinc and cadmium. It was …

Magnetic Properties Of Iron Rich Calcium Silicate Glasses And Their Aluminium Composites, Sylvia Menassa

Archived Theses and Dissertations

No abstract provided.

Evaluation Of Zinc Sulphate Electrolytes Containing Certain Impurities And Additives By Cyclic Voltammetry, D. R. Fosnacht, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

The polarization characteristics of acid zinc sulphate electrolytes containing various amounts of germanium and cobalt were examined by cyclic voltammetry. The effects of zinc and acid concentration, temperature, and surface preparation were also investigated. Small concentrations of impurities are shown to cause measurable changes in polarization behavior. Levels as low as 0.02 mgl-1 Ge and 0.1 mgl-1 Co can be detected using this technique. The actual mechanism of impurity behavior is more clearly delineated using this technique and evaluation of the data from these tests indicate that germanium and cobalt form local galvanic cells. The results of these short-term tests …

Mechanical Properties And Microstructure Examinations Of Aluminium-Steel Composites, Mervet Ibrahim Shenouda

Archived Theses and Dissertations

No abstract provided.

Solidification Of Aluminium Alloy Ingots, Hassan Abdel Kader Abdel Salam

Archived Theses and Dissertations

No abstract provided.