Engineering Commons^™

Preparation Of Copper Single Crystals By Means Of Powder Metallurgy Methods, Wei-Kung Chang

Masters Theses

"Since different mechanical properties of metals result from different grain size became known, the metallurgists have been interested in finding out the true nature of the grain boundaries. Consequently, several different theories concerning the mechanism of recrystallization, grain growth, and the structure of metals were advanced and studied. These threw much light on the difference of properties between polycrystalline metals and single crystals of the same metals. The single crystals of metals were studied because they enabled the investigator to determine the important points of metallic behavior. The first work on single crystals was rather obscure and limited to isolated, …

An Investigation Of The Weavability Of Wire With Observations On The Defects Of Wire And Wire Cloth, Walston Chubb

Masters Theses

"In the course of this year's work under the auspices of the Ludlow-Saylor research fellowship many problems of interest to the wire weaving industry have been investigated. Some of these problems have no academic novelty; others were not completed and have been laid aside for future investigations. The major problem for investigation this year was to discover a method by which the weavability of wire might be evaluated. A second problem for investigation was to discover the causes of some of the defects of wire and wire cloth. In addition to presenting the results of these investigations, this thesis represents …

The Investigation Of Color Modification As A Result Of Solid Solution, Bobby Lee Mornin

Masters Theses

"To the ceramic industry, color has long been one of its chief problems, not only in reproducing colors in the many complex silicate structures but in the development of stains that are stable at high temperatures and that are economically feasible for mass production. At the present time a stable high temperature red or yellow would be very desirable. Solid solution has been employed in ceramics to modify and thereby provide ceramic materials of different physical characteristics. The limited data available with respect to such solid solution serves to indicate that perhaps this state may serve as an important means …

The Effect Of Silicate Ion And Hydroxyl Ion On The Abstraction Of Potassium Ethyl Xanthate By Galena, Pao-Zung Wu

Masters Theses

"The purpose of this research was to investigate the effect of the silicate ion and the hydroxyl ion on the removal of potassium ethyl xanthate by galena; since the former ion is encountered during flotation owing to dissolution of silicates, and also sodium silicate being often used to disperse gangue minerals, and the latter one is encountered during floating in an alkaline circuit"--Introduction, page 1.

Wetting Properties Of Enamel Glasses And Relation To Adherence, Chandrakant Chhotalal Shah

Masters Theses

"Various investigators have tried to find the cause of adherence of enamel glasses to iron metal and they have put forward different theories to explain this phenomena of adherence. In spite of much work done on adherence, no theory has generally been accepted to explain the function of adhering oxides like cobalt, nickel or manganese, etc., in sheet iron ground coats. In this investigation it was thought to find out whether adherence promoting oxides have any effect on the wetting abilities of enamel glasses at elevated temperatures or not, and further, whether this different wettability caused by the different adherence …

Evaluation Of Quenching Media Using The End-Quench Hardenability Test, Subodh C. Das Gupta

Masters Theses

"The purpose of the thesis was to evaluate the quenching speed of different quenching media by studying their behaviour in relation to hardenabilities of steels, using the standard A.S.T.M. End-quench Test. At the outset an understanding of the term "Hardenability", so extensively used in industrial heat-treatment, is necessary, The property of a steel, of hardening on quenching to various depths beneath the surface is referred to as the 'Hardenability". It may simply be called the "susceptibility to hardening". Hardenability should be distinguished from the "Hardening capacity", which represents the magnitude of the hardness achieved. The chief factors which affect the …

An Investigation Of The Production Of Multicarbide Of Tungsten And Titanium From Wo₃ - Tih₂ - C Mixtures, Chi-Mei Hsiao

Masters Theses

"The purpose of this research was to investigate the possibility of producing the multicarbides of tungsten and titanium from a tungsten oxide-titanium hydride-carbon mixture. It appears to be worthwhile to carry out the reduction, carburization, and pre-alloying in one process, i.e. reducing tungsten oxide with the dissociated hydrogen from titanium hydride and the added carbon; then carburizing the reduced tungsten metal and dissociated titanium metal; at last, pre-alloying the mixture of TiC and WC. The replacement of titanium hydride with titanium oxide seems to be more direct, simple, and economical process; but the difficulty in the reduction of titanium oxide …

Barium-Tin Alloys, James Richard Whanger

Masters Theses

"The author attempted to produce alloys of barium and tin using metallic barium and barium hydride. Also, an attempt was made to study the phase diagram using thermal analysis and X-ray investigation"--Introduction, page 2

The Lithium Tungsten Bronzes, Shun Sheng Hsu

Masters Theses

"The 'tungsten bronzes are a series of anionic substitutional solid solutions of alkali or alkaline earth metal metatungstates and tungstic oxide. They are neither alloys or intermetallic compounds, the term "tungsten bronzes" was adopted because of their remarkable metallic properties -- e.g., high electrical conductivity, metallic luster on the crystal, and high specific gravity. Also owing to their intense and vivid colors and chemical inactivity it was possible to use them in the paint industry as a substitute for the so-called "bronze powders", the latter term is applied to the finely divided metal powders, such as aluminum, copper, brass, and …

Treatment Of Zinc Crusts By Vacuum Distillation, Chang-Hsu Shih

Masters Theses

"The purpose of this research is to investigate the possibility of obtaining reasonably pure silver from the zinc crusts by vacuum distillation in one step. The effect of temperature, pressure, particle size, and time of distillation will be determined. The behavior of other constituents in the crusts are also to be studied"--Introduction, page 5.

Comparative Study Of The Collecting Property Of Naphthenic Acids With Oleic Acid As Applied To Calcite, Hematite, Barite, And Fluorspar, Siddhi Nath Mukherji

Masters Theses

"The present investigation was undertaken to find out any comparable collecting property of some of the industrial naphthenic acids available in the market with that of commercial grade of oleic acid so that some information may be available in selecting naphthenic acids as flotation collectors. In the flotation industry, usefulness of oleic acid as non-metallic minerals collector is well established. On the other hand, the use of naphthenic acids as flotation collector has been reported only in few cases. Even in those cases, no attempt has been made to correlate their collecting properties with that of their physical and chemical …

Effect Of Transition Elements On The Transmittance Of B₂O₃ Glasses, Chandubhai Gordhanbhai Amin

Masters Theses

"For many years, boric oxide has been used extensively as a minor constituents in silicate glasses, because of its beneficial influence on their physical properties as well as on glass melting processes; but when used without silica or in too large proportion, the resulting glasses lack chemical durability...Because of its detrimental effect as a major constituent in silicate glasses or in borate glasses, very little work has been done on borate glasses, especially on colored borate glasses...The purpose of this investigation is to find out the effect of the transition elements on the transmission curves of the colored borate glasses"--Introduction, …

Effect Of Titanium Dioxide As A Mineralizer In Silica Brick, Henry Clay Brassfield

Masters Theses

"The magnitude of the thermal expansion of silica brick and its inability to withstand rapid temperature changes gives rise to problems of considerable importance in the manufacture of silica brick. In firing the silica brick, mineralogical changes occur in the quartzite from which the brick is made, in which minerals of lower specific gravity are formed. This results in a permanent expansion of the brick. These mineralogical changes have been thoroughly studied and considerable information is known on the different forms of silica produced at the higher temperatures. If the conditions of firing are such that these changes have progressed …

A Study Of The Gelation Of Air-Setting Refractory Mortars, James Irving Mueller

Doctoral Dissertations

"Three basic mortar formulae were used in this investigation, each mix having some different materials present and each having its own gelling characteristics. The study was directed along the theory that the dry materials used play an important part in the hardening. Certain admixtures were tested and several were found to improve the workability after storage. The presence of additional sodium ions in the mortar was found to be helpful in overcoming the gelation but these tended to lower the refractoriness of the mortar.

A study was made of the base exchange capacities of the dry materials and the material …

X-Ray Investigations Of The Metal Deposits Resulting From The Electrochemical Displacement Process, Cheng Chih Fang

Masters Theses

"The principle of electrochemical displacement has been well established in the science of chemistry and applied as a commercial process in some metallurgical processes, such as the cementation process and the immersion method of metal coatings. According to the EMF series of the metals, the upper, the more electronegative metal,* (*Here the term of 'electronegative' means the metal possessing high electrolytic solution pressure and going into the solution with the formation of positive ions. Some authors preferred to use 'electropositive' instead of 'electronegative', referring to the ions which are electropositive during dissolution.) will displace the lower, the more electropositive one, …

A Preliminary Investigation Of The Titanium-Copper Equilibrium System, August Robert Savu

Masters Theses

"The element titanium has a high degree of chemical activity at room temperature when in a finely divided condition. In the massive state this activity is only exhibited at high temperatures. The powdered metal is highly pyrophoric. Titanium forms quite stable sulphides and carbides, although these are subject to oxidation at high temperatures. It also form nitrides. Titanium being a transitional element forms hydrides with hydrogen which are stable at ordinary temperatures, but which dissociate at red heat liberating the hydrogen and leaving the metallic titanium in a very active state. Alloys are formed with such metals as aluminum, manganese, …

Reduction Of Zinc Sulphide In A Vacuum, Tien-Shih Liu

Masters Theses

"The successful large scale commercial application of high vacuum for high temperature metallurgical operations is a comparatively new development. The use of Pidgeon and the carbothermic processes for the production of magnesium during the war forced a perfection of both equipments and techniques for high vacuum operations. This opens broadly the way for a great expansion of vacuum metallurgy. Vacuum operation is thus no more a laboratory method - it is a kind of industrial practice. Many metallurgical operations, which cannot be carried out by ordinary processes, are made feasible when conducted in a reduced pressure. typical examples are the …