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The partial constitutions of the Au-Ge-X and Au-Pb-X ternary alloys have been investigated, where X is a metallic element, selected from the sub-groups period 1m and rrm of the periodic table (In, Ga, Zn, or Cd), which forms one or more stable compounds with gold, but which forms no stable compound with Ge and Pb. The Smith Thermal Analysis Method, supplemented by metallographic and X-ray techniques, was used to determine the constitutions of the ternary systems. Eutectiferous, pseudobinary systems were found between Ge and the stable congruent intermediate compounds, AuIn, Auln2' AuGa, AuGa2' AuZn and AuCd. The solubility of Ge in the AuX compounds was not determined directly. However, it was 1.3 at.% Ge for Zn and Cd containing alloys and less than 1.0 at. % Ge for In and Ga containing alloys at the eutectic temperatures, which is in accordance with the Hume-Rothery rule. Ternary eutectic points were also determined in the Auln-AuIn2-Ge, Auln2-In-Ge and AuGa-AuGa2-Ge partial ternary systems. No evidence of liquid immiscibility was found in any of these ternary systems. The experimental results obtained were in good agreement with computed features of the diagrams. However, pseudobinary systems were not found between Pb and the stable congruent melting intermediate compounds, AuGa, AuGa2, AuZn and AuCd (the AuIn-Pb and AuIn2-Pb sections had already been investigated). The evidence of an extensive liquid immiscibility was found in each of these systems. The miscibility in the liquid state was found to decrease progressively down group IV when the elements of this group react with AuX compounds, which can be attributed to the progressive increase of the atomic size and decrease in electronegativities and solubility parameters of the elements, down this group. Two rules were derived to relate the liquid immiscibility/miscibility of ternary systems. One of the rules based upon the atomic sizes and melting points of the constituent elements showed a fair agreement with many systems. However, the other rule based upon the solubility parameter and electronegativities of the constituent elements showed good agreement with immiscible systems, but gave a poor predictability for miscible systems. The lower temperature equilibria of the Au-rich portion of the Au-Sn binary phase diagram are not well defined. So, long term heat treatment of samples at appropriate temperatures and compositions was carried out. Optical microscopy and SEMIEDAX techniques were employed and hence the low temperature equilibria of the Au-Sn binary system have been amended.

This thesis describes an ion irradiation study of ordered Cu<sub>3M/sub>Au. Argon, Copper and Krypton ions of 50 and 100keV were implanted to nominal doses of 10¹¹ ions cm^-2 both at room temperature and at liquid helium temperature. The damage induced at low temperature was observed in-situ and after subsequent warming to room temperature. The collapse of collision cascades to vacancy dislocation loops was observed to occur with moderately high probability under all irradiation conditions at low temperature, with no subsequent increase in the number of loops on warming. Comparison of the collapsed fraction of cascades at low temperature with that produced by room temperature irradiation revealed that the collapse process is more efficient in the latter case. An increase in collapse probability with ion mass was also observed, although no dependence on ion energy was found over the range investigated. Quantitative analysis of the disordered zones which result in ordered Cu₃Au at individual cascade sites revealed that cascades which had collapsed to loops generally produced larger disordered zones. Additionally, increases in disordered zone size with ion mass, ion energy and irradiation temperature were identified. The observation that disordered zone sizes exceed the theoretically predicted cascade dimensions for the case of the highest energy density in this study (50keV Kr) is interpreted as evidence for leakage of energy from the cascade region to the surrounding lattice. A model is proposed which attributes the observed cascade collapse behaviour to vacancy migration during the cooling of the cascade region being systematically directed toward its centre, and accounts for the observed disordered zones in terms of extensive atomic rearrangement during the cooling. The major factors identified as controlling this vacancy and atomic motion are the initial spatial distribution of energy and vacancies within the region, and the rate at which the region cools.

Thesis (PhD)--University of South Australia, 1997

Includes bibliographies. / 2 v. : [1] ill., [1] map ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis aims to tabulate information on the pattern of international trade in chromite and ferrochromium in a systematic form for the whole world during a period of more than fifty years prior to and including 1980. The study describes the main features of the international trade pattern, and outlines the various factors that have had an influence in determining the pattern of international trade in chromite and gerrochromium. / Thesis (Ph.D.)--University of Adelaide, Dept. of Commerce, 1997?

254 leaves : ill. + graphs, tables, photo ; 26 cm / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering, 1976

107 leaves : ill., photos ; 25 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering,1972

Thesis (Ph. D.)--University of Washington, 1988. / Vita. Includes bibliographical references.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Dec. 5, 2007). PDF text: xi, 137 p. : ill. ; 7 Mb. UMI publication number: AAT 3271927. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Aluminum; quench sensitivity; heating rate. Includes bibliographical references (p.67-68).