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In a high competitive market, the development of new alloys, new applications, price pressure and increases in product forces quality wire manufacturers to ask for increased mechanical characteristics without losing conductivity. As a particular example, development of new copper alloys such as CuZr, CuSn, CuMg and CuAg have been developed for automotive cables. Continuous extrusion is currently the most prevalent manufacturing technology in terms of chemical composition, mechanical properties and electrical properties, resulting in the production of high quality rods. However, continuous casting has good potential to also be adapted to the mass production of various copper alloy wires. Comparison of the continuous casting process to other thermal methods such as continuous extrusion highlighted that, in general, the mechanical properties of continuous cast materials are lower than that of material from thermomechanical methods. However, continuously cast alloys rods are cheap to produce and simple to manufacture. So, the key aims of this research were (a) to increase the understanding of the solidification behaviour of some industrially important continuously cast non-ferrous alloys, (b) to define an increased range of alloys and downstream processing techniques which could be performed using continuous casting technology, (c) to determine improved continuous casting process validation capabilities and (d) to define new capabilities in terms of casting equipment. The majority of this PhD thesis was focused on improving the current continuous casting technologies and development of casting capability of a range of copper and non-copper alloys. The analysis in this PhD thesis illustrated that the metallurgical and mechanical properties of components mainly produced by continuous casting are acceptable, and that this method could be a replacement production method for materials such as lead alloys and various copper alloy rod, e.g. CuMg and CuAg. However, in the case of Deoxidized High Phosphorus (DHP) copper tubes, the performance of the as-cast material was significantly lower than that of from extrusion or planetary rolling process. This PhD thesis also makes comment on the parameters controlling the solidification process in order to improve the quality of as cast alloys rods/tubes. Using specific casting parameters, a significant difference based on tensile strength and elongation percentage has been illustrated, and it was found that these parameters could improve the mechanical properties of continuously cast copper rods and tubes. This significant difference is as a result only of the change in casting parameters, with no difference in the chemical composition of the material, or the general method of production. These parameters were (1) water flow rate, (2) casting speed, (3) pull distance, (4) melt temperature, (5) cleanout cycle, (6) continuous casting direction and (7) super-cooler size. The new knowledge created and understanding gained during the course of this research improved the company’s capability in the marketplace, enabling it to supply equipment with improved competitive capabilities and the potential to enter new markets, leading to sales growth in existing sectors and significant longer-term growth into new technically challenging application areas.

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This thesis aims to examine the modes of production and the sources of metal supply for Migration period bow brooches, concentrating on a single form, the Anglian cruciform brooch. The thesis is in two volumes; text and bibliography (volume 1), catalogues, tables, illustrations (volume 2). The text is in six chapters. Attitudes to artefact studies are briefly discussed in Chapter 1 and the techniques employed in this study are outlined. Chapter 2 places the cruciform brooch forms into a simple hierarchical typology by formal similarity. A relative chronology is gained by contextual evidence, with absolute dates given by associations with other artefact types. Similarities between early English and continental forms are shown to be adequate to suggest importation, during the first half of the fifth century. Frisian and north German brooches have a special place in this system. Parallel stylistic development persisted during the second half of the fifth century but sixth-century English brooches are well distinguished from their continental contemporaries. Simple brooch types are thought to have had a long period of production and use. By examining methods of casting and assembling cruciform brooches, Chapter 3 establishes the types and ranges of technical variation observable. Some of these technical attributes provide links between England, Frisia, northern Germany and Denmark. English brooch manufacture is diverse throughout the period under study. Norwegian metalworkers developped a very different style and the technical evidence suggests a movement towards standardisation and mass production. In Chapter 4 we discover the types of alloy used and discuss the likely sources. Initially the alloys used were leaded brasses or bronzes. By the sixth century, copper alloys were commonly very impure. It is suggested that recycling provided a major part of the raw materials for cast copper alloys. Imports of copper alloys from France or the Celtic regions of Britain are relegated to a position of minor importance. The chemical compositions of Norwegian, Frisian, north German and Dutch cruciform brooches demonstrates access to high-tin, high-purity bronzes prevailed throughout the period. Brasses and mixed alloys were also available, probably originating from scrap. With the exception of Frisia, which appears to be more similar to Kent, alloy supplies were similar throughout the Scandinavian and continental cruciform brooch production. Chapter 5 provides a synthesis for these findings. Plans are given for a project extension into other regions (Chapter 6).

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In-situ copper leaching at BHP Copper's San Manuel open pit mine was established in 1986. Currently, over a thousand wells on the benches of the open pit mine are simultaneously injecting and pumping sulfuric acid solutions. A large-scale reconfiguration of the well field in 1996 led to a dramatic, yet temporary, increase in copper pounds, apparently due to changes in flowpaths. While the first reconfiguration was accomplished by means of hydrologic intuition, a question arose regarding the issue of whether subsequent reconfigurations supplemented with additional smaller scale characterization could ultimately lead to increased copper production. To study this question, two fifty-well sites were selected within the in-situ leach well field. Because in-situ leaching involves the movement of fluid within the subsurface, hydrology is a natural context in which to study the process. The desire to optimize well-to-well in-situ leaching for enhanced copper recovery through the fundamental understanding of important hydrologic mechanisms is the primary motivation for this dissertation. Hydrologic testing in San Manuel is inherently challenging due to the hydraulically dynamic environment. A hydraulic cross-hole testing procedure termed "Cyclic Pulse Testing" (CPT) was used to overcome this issue. Over 100 pressure responses obtained via CPT at the two test sites were examined by means of type curve analysis. The spatially distributed hydraulic parameters were analyzed within the framework of geostatistics. The kriged heterogeneous hydraulic conductivity fields were inputted into a numerical flow and transport model to study, along with other issues, the impact heterogeneity has upon the in-situ leaching process. A number of conclusions were reached based upon the investigation of the two test sites. Comparison between single-hole and cross-hole hydraulic tests revealed the probable presence of a low permeable skin surrounding the wells. By far, the most important hydrologic mechanism controlling the in-situ leaching process in San Manuel was the massively induced hydraulic background gradient, in places, on the order of 35°. Modeling revealed insignificant differences on the sweeping efficiency of the formation between heterogeneous and homogeneous simulations. However, due to the twodimensional nature of the collected data, additional three-dimensional information may lead to a different conclusion.