Thesis (Ph. D.)--University of New South Wales, 2002. / Also available online.

Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on December 28, 2007) Includes bibliographical references.

The effect of nonstirred aqueous Portland cement solution on the corrosion rates of zinc and cadmium metal using Tafel extrapolation and linear polarization measurements has been investigated. Results indicate that for the corrosion systems under investigation, zinc metal has a higher corrosion potential and lower corrosion rate than cadmium metal.

M. Tech. Metallurgical Engineering / Mild steel is vulnerable to corrosion; this behaviour affects the material strength and electrochemical behaviour during industrial application. Mild steel also has poor tribological resistance; its application for the components of machines, however, requires good tribological property. The cost incurred from equipment failures, properties loss and increased production overheads makes is imperative to enhance mild steel's electrochemical and tribological properties. Electroless nickel plating has found extensive use in various industries attesting to its exceptional properties. The effect of bath parameters on the electroless plating process is of importance as this affects the adhesion, morphological behaviour, electrochemical properties and uniformity of coating. The key aim of this research is: To generally improve the understanding of the effect of electroless binary and ternary alloys on the corrosion and wear resistance of mild steel using weight loss method, potential measurement, linear polarization and tribological sliding wear tests. This work studies the effect of temperature, concentration, deposition time and the inclusion of Tin (Sn) as a third addition to the electroless bath. Corrosion and wear behaviour of the electroless plated mild steel was studied.

Thesis (Ph. D.)--Murdoch University, 1991.

Thesis (Ph.D.) OGI School of Science & Engineering at OHSU, June 2008. / Includes bibliographical references.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 65-68). Also available via the Internet.

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Includes bibliographical references. / by David Malcolm Kundrat. / Sc.D.

In electrical contacts, thin films of nickel and gold or silver are traditionally plated on top of a copper base plate to provide corrosion resistance and wear protection. Most recently, the rising cost of noble metals and intensified competition in manufacturing technology has driven the industry towards thinner plating layers, which gives rise to questions regarding how interfacial contact and wear is affected by plating thickness and material characteristics. This study uses a combination of finite element analysis and ex-situ wear measurement to determine the effect of gold plating thickness on wear performance under linear reciprocating sliding contact. Correlations between predicted and measured results lead to insight into the stress state within the multi-layer system under contact conditions as well as a wear map for gold platings that can be used to inform future connector designs. The middle layer material, Ni, is relatedly inexpensive, but takes a relatively long time to deposit. Because this deposition time has a direct influence on the cost of manufacturing, it is important to reduce the Ni thickness as well. This project thus determines how different combinations of Ni and Au properties influence wear and subsurface layer exposure, which is critical for determining the makeup of future, low-cost, connector designs.

Hydrogen embrittlement is a mechanism by which hydrogen enters a metal, causing a loss in strength and ductility. This phenomenon is of great concern to the oil and gas industry as deep-sea wells operate in high temperature, highly acidic and high stress conditions. Nickel-based superalloys are ideal for use in such environments due to their high strength and exceptional resistance to both corrosion and hydrogen embrittlement. Alloy 945X is a newly developed nickel-based superalloy that has been specifically designed for use in downhole applications. This thesis compares the performance of hydrogenated Alloy 945X with the more established oil and gas grade Alloy 718. The hydrogenating environment of an oil well was simulated via cathodic polarisation. The effect of hydrogen content on the tensile performance of both alloys was studied, alongside fracture and microstructural analysis. A new video-recording technique was employed to investigate the crack initiation and propagation behaviour of both alloys, alongside in-SEM tensile testing. The diffusive nature of hydrogen in Alloy 945X and Alloy 718 was explored. With the use of a ppm-sensitive hydrogen analyser, it was possible to measure the rate at which hydrogen enters and outgassed from both materials as well as the saturation conentrations. Outgassing behaviour was also examined using X-ray diffraction and nano-indentation. The depth of brittle fracture in cathodically charged tensile specimens was correlated with Fick’s diffusion calculations and the critical concentration for embrittlement calculated. In a similar method, a parameter (based on diffusion coefficient calculations) that describes the rate of embrittlement in a material was proposed.