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This research investigates metallurgy during the sixteenth and seventeenth centuries in Colombia. Drawing on theories from Material Culture Studies, Landscape Archaeology and the Anthropology of the Senses, and adopting a multidisciplinary approach that includes archaeological evidence, documentary sources and ethnographic interviews, this study aims at documenting and analysing what happened to metallurgy after the encounter. The study focuses on the town of Mompox, a World Heritage Site, in the Momposino Depression in northern Colombia. Here, a long-lasting metalwork tradition survives not only in the memories of the oldest goldsmiths but also in delicate silver filigree work. The study focuses on the relationships that emerged between things and people within different landscapes and in light of this it offers an alternative perspective to examine processes of change and transformation, movement, continuity, resistance, techniques, and experiences. This thesis argues that the entangled relationship among individuals, objects and landscapes brought important tensions and sensorial experiences into play, which in turn altered, resignified, modelled and influenced the metallurgical activity. This research is the first attempt at studying metalwork during the early colonial period in Colombia from a multidisciplinary perspective. It discusses the material record left by metalwork in the past that was recovered during excavations in Mompox. Archaeometallurgical analysis' results contribute to the discussion. From a historical point of view, primary sources, chronicles of Indies and official reports shed light on goldsmithing activity, the characteristics of workshops, and the social, economic and political circumstances of metalwork activity within this time frame. Finally, from an anthropological perspective, interviews with older goldsmiths in Mompox provide an ethnographic dimension to help understand present-day metalwork and to search for traces of the material culture remains.

A fairly new technology used to produce metallic components is powder metallurgy (PM). Among the advantages with this technique are decreased cost of production for complex-shaped parts, new alloys are made possible, reduced end processing, less material loss, and vibrational damping effects. The downside is the number of pores created which can alter the tribological properties of the material. The focus of this report is to investigate how lean PM steel behaves under tribological contacts.  Friction and wear will be investigated using a pin-on-disc setup to mimic the sliding part of a gear tooth mesh. Previous studies show that the amount of wear, and if the wear increases or decreases with increased density is dependent on the degree of porosity and the pore size. This means that the wear might be minimized by optimizing the number of pores in the material and their shape and size. The result of this study shows that the friction coefficient decreases with increasing density. The wear coefficient show signs of the same correlations but further tests are needed. The main wear comes from adhesive wear, with signs of abrasive wear. The amount of abrasive wear seems to increase with an increase in density, supporting previous studies claiming that pores can trap wear debris and decrease the number of abrasive particles in the contact.

This study was conducted as part of an ongoing research programme to evaluate and implement change in the School of Process and Materials Engineering (PRME) 1002 course curriculum to effect positive results in academic achievement, thus increasing throughput rates of first-year Chemical and Metallurgical engineering students. This study designed and implemented a cognitive mediated intervention programme adapted by Professor Skuy (2003) from Feuerstein's Instrumental Enrichment (1980) programme. The aim was to see if an extended programme period of time, 12 weeks as opposed to 5 weeks implemented in an earlier study by Viviers (2004), would significantly improve the academic performance of the sample of 20 first-year Metallurgy students as measured by the mid-year and end-of-year examination results. The study also aimed to find out if the cognitive mediation intervention programme would significantly improve the intellectual functioning of the Metallurgy students. The results show that mediating cognitive functions significantly improved the intellectual functioning of the sample of 20 students as measured by the pre- and post-test scores of the Cognitive Assessment System (Das & Naglieri, 1993). However, no significant improvement was found in the academic achievement of the students as measured by the examination results. Accordingly it was concluded that the extended period of time (12 weeks), was sufficient time to improve intellectual functioning of Metallurgy students, but insufficient time for this to transfer into academic achievement for the Metallurgy students. The study highlighted the difficulty of transfer in the engineering context, as well as the continued problem that first-year students have with the complex conceptual nature and demands of the PRME (1002) course.

"The goal of heat treating manufactured steel components is to enhance the characteristics of the metal so that the components meet pre-specified quality assurance criteria. However, the heat treatment process often creates considerable distortion, dimensional change, and residual stresses in the components. These are caused mainly by thermal stresses generated by a non-uniform temperature distribution in the part, and/or by transformation stresses due to the volume mismatch between the parent phase and product phases that may form by phase transformation. With the increasing demand for tighter dimensional tolerances and better mechanical properties from heat treated components, it is important for the manufacturer to be able to predict the ability of a component to be heat treated to a desired hardness and strength without undergoing cracking, distortion, and excessive dimensional change. Several commercial softwares are available to accurately predict the heat treatment response of wrought steel components. However, these softwares cannot be used to predict the heat treatment response of steel components that are made by powder metallurgy (PM) processes since these components generally contain pores which affect the mechanical, thermal, and transformation behavior of the material. Accordingly, the primary objective of this research is to adapt commercially available simulation software, namely DANTE, so that it can accurately predict the response of PM steel components to heat treatment. Additional objectives of the research are to characterize the effect of porosity on (1) the mechanical properties, (2) the heat transfer characteristics, and (3) the kinetics of phase transformation during heat treatment of PM steels."

Listening to Birth asserts that structures of power reproduce themselves by instituting particular modes of listening and sound production. Situating my research within feminist sound studies, I argue that meanings conjured around the audible, material bodies of women were carefully crafted by elites in antiquity, in order to construct gendered ideologies of kingship, civilisation, and nature. I examine these power dynamics as expressed in mythic and magical texts and iconographies, dating from the Bronze Age to later Roman antiquity. Throughout the thesis, I examine the development of symbolic systems and narrative tropes that linked mining and metallurgy with reproduction and vocality. My analysis emphasises how the invention of nature was accomplished, in part, through a metallurgical reclassification of the voices and sexualities of women as indiscrete phenomena: womb, mouth, and voice were elided with mining and smelting to form a unified semantic realm. I argue that this invention of ‘vulvar vocality’ reclassified female sounds as illicit, providing a plaform for the removal of women from the public sphere. I attempt to connect the gendered discourse found in myths and magical rituals to the political and economic domain of state-craft, to demonstrate the importance of hegemonic mythopoeic control of audible female reproduction for establishing ideologies of colonisation and extraction. I link analyses of texts and iconographies from the Bronze Age Mesopotamians, Hittites, Canaanites, Minoans, and Egyptians to later materials from the Iron Age Greeks, Israelites, and Romans—my goal is to demonstrate both the ubiquity and the continual reproduction of metallurgical ideology across the ancient world. I also present my preliminary research into the lasting impact that antique notions of vulvar vocality had on later state-craft. I begin to trace the preservation and elaboration of antique metallurgical literature by Byzantine and Islamic scholars, who in turn exerted strong influence on the Ottomans and late medieval and early modern Europeans. I outline future work to investigate the exponential rise of entrepreneurial metallurgy in late medieval and early modern Europe, arguing that this metallurgical discourse provided symbolic re-enforcement for the rapidly-accelerating mining and metal trade that formed the core of European colonial expansion. I suggest that vulvar vocality was central to early modern metallurgical, demonological, and colonial discourse, and that specific female vocalities and silences were purposefully crafted into the colonial project in order to forcibly redefine women, along with the lands and children stolen from them, as mere natural resources.

This is the first major art historical study of Elkington & Co., the British art-metalwork company that from c.1840 invented and patented methods of electro-depositing gold and silver, which they developed artistically and commercially into the modern industrial art of electro-metallurgy. It analyses how Elkington's syntheses of science and art into industrial manufacturing processes revolutionized the design and production, replication and reproduction of precious metalwork, metal sculpture, and ornamental art-metalwork, and why the art of electro-metallurgy, the world's first electrical art, exemplifies the social, and cultural change of the mid-Victorian era. This PhD thesis studies Elkington's technical development from c.1840-1900, analyzing how they developed new methods of gilding and plating, and important collateral technologies. It identifies key people in the company, and analyses the chronology of scientific discoveries that shaped the industrial processes and artistic practices at their manufactories in Birmingham. It then analyses the development of the company's creative strategy, and identifies key people whose artistic contributions collectively shaped the evolution of the art of electro-metallurgy. It provides the first study of Elkington as non-precious metals manufacturers, identifying and analyzing the key artworks that they produced in copper and copper alloys as 'bronzists,' and examines how Elkington applied the art of electro-metallurgy to the manufacture of monumental statues. By critically analyzing key sculptures it demonstrates how Elkington became the preeminent British bronze foundry of the mid-Victorian era. It concludes with a study of Elkington & Co.'s oeuvre from 1851-1878, and analyzes how their art of electro-metallurgy was influenced by the technical and stylistic eclecticism of l'orfèvrerie française of the French 2nd Empire. It describes how, from 1853- 1899, Elkington employed three Frenchmen as their chief artists: Pierre-Emile Jeannest, Auguste Willms, and Léonard Morel-Ladeuil, who further elevated the company's artistic reputation. It concludes with a detailed analysis of Elkington's masterpiece, The Milton Shield (1867) and analyses how its publication as electrotype reproductions in America exemplified the art of electro-metallurgy.

Thesis (Ph. D.)--Oregon Graduate Center, 1988.

The metallurgy and superconductivity of the Nb-Ti-Ta ternary alloy system were studied. The Nb-Ti, and Ta-Ti binary samples, and Nb-Ti-Ta ternary samples were precipitation heat treated under different schedules. After the precipitating heat treatment, the samples were characterized by X-Ray Diffraction (XRD) techniques. Equilibrium binary and ternary phase diagrams based on the different alloy compositions and heat treatment temperatures were developed. The Ta-Ti binary phase diagram is very close to the ASM standard phase diagram. The ��-phase boundary of Nb-Ti binary phase diagram developed here is at a higher temperature relative to the ASM standard one. A working ternary equilibrium phase diagram for the Nb-Ti-Ta system has been developed that is based on the experimental measurements and quantitative thermodynamic calculations. Measurements of superconducting critical temperature, Tc, show a good agreement with previous measurements of Tc in the ternary alloys. / Graduation date: 2002

In the scope of this study, TiNi foams with porosities in the range of 39-64 vol% were processed from prealloyed powders by Mg space holder technique. Porous TiNi alloys displayed homogeneously distributed spherical pores with interconnections, which is suitable for bone ingrowth. Porous Ti-50.8 at%Ni alloys were processed by sintering at 1200 &deg / C for 2 h to analyze the microstructure as well as mechanical behavior. SEM, TEM and XRD studies were conducted for the characterization of microstructure and phase analyses in addition to the mechanical characterization performed by monotonic and superelasticity compression tests as well as compressive fatigue tests. It was observed that stress required to trigger martensitic transformation was decreased via increasing porosity. The monotonic compression test results also indicated that altering the porosity content of TiNi foams leads to different monotonic compression behaviors. It was observed that the foams display more bulk deformation like behavior as a composite structure composed of TiNi and macropores when the porosity content was low. As the porosity content has increased, the struts became more effective and deformation proceeds by the collapse of favorable struts. On the other hand, cyclic superelasticity tests results indicated that maximum achieved and recovered strain values at the end of fifth cycle increase while the fraction of strain recovered at the end of fifth cycle decreases with decreasing porosity content. Furthermore, the fatigue lives of the processed foams were observed to vary within a band which has a width decreasing with decreasing &sigma / max / &sigma / y yielding an endurance limit ranging in between 26-89 MPa or 0.5-0.6 &sigma / y. Fractography studies on the failed foams after fatigue testing revealed that the failure occurs by the coalescence of micro-cracks initiated from pore walls leading to macro-cracks aligned at 45o with respect to the loading axis. In addition to the mentioned characterization studies, the effects of sintering temperature and time on TiNi foams with 58 vol% porosity as well as heat treatment on the microstructure and the mechanical behavior of TiNi foams with 49 vol% porosity were analyzed with SEM and compression tests. Aging of TiNi foams with 49 vol% porosity at 450 &deg / C for 1.5 h has shown that the presence of Ti3Ni4 precipitates improve the superelastic response.