Tesi sul tema "Copper alloys"
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1
Wood, G. P. "Electrodeposition of copper-zinc alloys". Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355428.
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2
Hamilton, M. A. "The optical properties of oxide films on copper and copper alloys". Thesis, London Metropolitan University, 1985. http://repository.londonmet.ac.uk/3378/.
Testo completoAbstract (sommario):
Suitable conditions were selected to allow thin, thermal oxide films consisting of cuprous oxide only to be grown on copper and dilute copper alloy substrates. The identity of the oxide was confirmed by x-ray diffraction and coulometry. Spectral measurements covering the wavelength range 350 - 750 nm were made using an automatic, self-nulling ellipsometer. From this data the optical constants and thickness of the oxide films were computed and compared to those of the bulk oxide. The optical constants of the oxide were found to depend on the thickness of the film and the identity of the alloying addition in the substrate. The effect of different substrates on the optical constants of cuprous oxide was tested by growing thin cuprous oxide films on gold and glass substrates. Optical property changes of the oxide are attributed to space-charge effects existing at the substrate/oxide interface.
3
Durandet, Y. C. "Rapidly solidified high-copper dental amalgam alloys /". Title page, contents and summary only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phd949.pdf.
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4
Gao, Guilian. "Dealloying of copper alloys in aqueous solutions". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316771.
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5
Smith, Jacob A. "Electrical Performance of Copper-Graphene Nano-Alloys". Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1550675878730599.
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6
Cottle, Rand Duprez. "Isotropic copper-invar alloys for microelectronics packaging /". Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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7
Athavale, Saurabh. "Effect of Cu concentration and cooling rate on microstructure of Sn-3.9Ag-XCu". Diss., Online access via UMI:, 2006.
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8
Vega-Garcia, Jean-Paul. "Microstructural Investigation of Precipitation Hardened CuNi2S+Zr Alloys for Rotor Applications". Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2157.
Testo completoAbstract (sommario):
Industrial generator components experience high stresses and electrical fields during their service life. Material integrity is key in guaranteeing component performance. CuNi2SiZr, used as rotor wedges in generators, serve to maintain rotor slot content in place while experiencing high centrifugal stresses and low cycle fatigue during start and stop at elevated temperature. The quality and integrity of this material in service can be directly related to its microstructure, which is determined by the processing procedures of the wedges. In this study, the microstructure development in this material is evaluated to eliminate grain boundary defects by optimizing processing parameters, determining the best temperature/time combination for precipitation hardening, and determining cold work effect on aging parameters. Two chemistries containing Nickel-to-Silicon ratios of 3.2 and 3.8 were selected for analysis. Cast samples were hot extruded, cold worked, and precipitation hardened. Parameters were varied at each processing step. Five different levels of cold work (4, 5, 7, 10 and 13%) were evaluated using 5 different aging temperatures (450, 460, 470, 490 and 500°C). Each processing parameters' effect on microstructure and subsequently on hardness, conductivity, and tensile strength was recorded to assess material performance and identify grain boundary defects origination. Finding of this study identified observed grain boundary defects, using Transmission Electron Analysis, as voids/micro-tears. These defects on grain boundary are detrimental to low cycle fatigue, creep rupture and tensile strength properties and important aspects of the material performance. Grain boundary defects were observed at all levels of cold work, however, origination of defects was only observed in grain sizes larger than 50µm. The strengthening phases for the CuNi2Si+Zr alloy system were identified as Ni2Si and Cr3Si. The Nickel-to-Silicon ratio had an evident effect on the electrical conductivity of the material. However, aging benefits were not clearly established between the two Nickel-to-Silicon ratios.M.S.M.S.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Materials Science & Engr MSMSE
9
Tarhan, Elif. "Ageing Characteristics Of Copper Based Shape Memory Alloys". Phd thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/593541/index.pdf.
Testo completoAbstract (sommario):
Martensite-to-Beta transformation temperatures of CuAlNiMn and CuAlNi shape memory alloys has been determined by differential scanning calorimetry (DSC). In CuAlNiMn alloys, each new betatizing treatment has resulted in randomly varying transformation temperatures on the same specimen and an anomalously diffuse and serrated Martensite-to-Beta transformation peaks in the first cycle. Therefore, as quenched alloy samples were thermally cycled for three times in DSC prior to ageing to obtain thermally stable and reproducible transformation temperatures and to eliminate the anomalous effect of betatizing on the transformation temperatures.
CuAlNiMn alloys were aged in martensitic condition at temperatures in the range 80
C to 150&
#61616
C for 24 hours to 312 hours ageing periods. Both A_s and A_f temperatures have increased with ageing temperature and time while M_s and M_f temperatures have not changed during martensite ageing. Transformation temperatures of CuAlNi alloys, on the other hand, have not changed during martensite ageing. In this respect, CuAlNiMn alloys were found to be more prone to martensite stabilization than the CuAlNi alloys. Through Transmission Electron Microscope investigation in the Cu-12.6wt%Al-5.9wt%Ni-1.8wt%Mn alloy aged at 150&
#61616
C for 312 hours has revealed no sign of precipitate formation and it has been concluded that the &
#65533
precipitates pinning martensite boundaries&
#65533
mechanism could not be responsible of martensite stabilization. Beta phase ageing of CuAlNiMn alloys at temperatures 200&
#61616
C, 230&
#61616
C, 250&
#61616
C and 270&
#61616
C, have drastically shortened the periods for stabilization to the extent that &
#946
-to-M transformation completely ceases. With regard to the Manganese content, highest Manganese bearing alloy was the one stabilized first and the lowest manganese containing one was the longest lasting alloy during beta phase ageing. Beta stabilization was not observed in any of the four CuAlNi alloys at the end of 96 hours ageing at 200&
#61616
C while beta stabilization was realized after 26, 38 and 11 hours ageing at the same temperature in the three Mn containing alloys studied. In conclusion, on the basis of ageing studies at 200&
#61616
C, with regard to beta stabilization, CuAlNi alloys were found to be more resistant to high temperature ageing than CuAlNiMn alloys. Equilibrium &
#947
_2 and &
#945
phases were observed with coupled-grown lamellar morphologies in Cu-13.6%Al-3.0%Ni alloy aged above 400&
#61616
C.
10
Setna, R. P. "Study of the decomposition of copper-cobalt alloys". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239277.
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11
Richards, G. M. "Deformation processes during creep of copper-cobalt alloys". Thesis, Swansea University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638656.
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12
Vassiliou, George E. "The erosion-corrosion behaviour of copper-nickel alloys". Thesis, University of Glasgow, 2001. http://theses.gla.ac.uk/2458/.
Testo completoAbstract (sommario):
The research focuses on an investigation of the erosion-corrosion behaviour of Cu-Ni-base alloys in aqueous environments. The principal objectives of the research were to examine the fundamental mechanisms of the erosion-corrosion attack. The work was focused on a standard Cu-10%Ni alloy that is used extensively in a variety of marine industries and on Marinel alloy, which is a high strength precipitation-hardened copper-nickel alloy. Erosion-corrosion tests were carried out for exposure times up to 72 hours, in a solid free 3.5% NaCl solution impinging at velocities of 2.38-86 m/sec, (Re=4500-86000), at temperatures of 19°C and 35°C. The overall erosion-corrosion behaviour and the direct corrosion component were monitored using gravimetric and electrochemical-monitoring techniques. Contributes from mechanical erosions were assessed by cathodically protecting specimens under impingement conditions. The research also considered the influence of various parameters such as temperature, time, velocity, salinity variations, and impingement angle. The extent and morphology of material deterioration and protective film formation under various environmental conditions were assessed, utilizing surface profiling equipment and light optical and scanning electron microscopy. The work has quantified the complex contributions of corrosion, erosion and synergy to the overall erosion-corrosion material loss. An important finding was the substantial superior erosion-corrosion resistance of Marinel compared to the standard Cu-10%Ni, with interesting effects of impinging velocity and time of exposure being observed. Also this work provided some clear evidence of significant potential benefits in terms of erosion-corrosion resistance, obtained by the exposure of Marinel at the elevated temperature.
13
George, Faith Olajumoke. "Chromium-free conversion coating of aluminium-copper alloys". Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/chromiumfree-conversion-coating-of-aluminiumcopper-alloys(5176c8af-02af-44a8-a47f-44b5a0c2585c).html.
Testo completoAbstract (sommario):
Aluminium alloys are frequently pre-treated by a conversion coating before application of an organic coating in order to improve the corrosion resistance and adhesive properties of the surface and the corrosion resistance provided by the system. Chromate-containing conversion coatings are commonly used for this purpose. However, legislation limits future use of hexavalent chromium compounds due to their toxic and carcinogenic nature. Therefore, alternative, so-called chromium-free conversion coatings are being developed that are more environmentally-compliant.The purpose of the present work has therefore been to contribute to a better understanding of how the aluminium substrate affects the formation and properties of conversion coatings for adhesive bonding. In particular, a chrome-free zirconium-based conversion treatment process has been investigated as a possible replacement for conventional chromate conversion treatment. The influence of the conversion time on the thickness of the formed layer on pure aluminium was investigated using complementary surface analytical techniques. The conversion time was varied between 30 and 600 seconds.In this study, the structure and composition of zirconium-based chromium-free conversion coatings on magnetron sputtered superpure aluminium and a range of aluminium-copper alloys were characterised as a function of immersion time in the aqueous conversion bath to understand the mechanism of coating formation and protection. However, the presence of copper significantly influences the coating development and ultimately the performance of the conversion coatings formed on binary copper-containing aluminium alloys.The morphology and composition of the coatings have been probed using transmission electron microscopy, Rutherford backscattering spectroscopy and glow discharge optical emission spectroscopy, with loss of substrate through growth of the conversion coating also quantified. A comparison of the RBS spectra obtained for the superpure aluminium specimens after different immersion times revealed that zirconium (Zr) and oxygen (O) peaks were wider for longer immersion times, indicating thickening of the coating with increased immersion times. Thus, increasing the immersion time resulted in an increase in coating thickness but little change in coating composition occurred as determined by the RBS RUMP simulations. Alloying decreases the coating thickness, as well as metal consumption. Here, aspects of the corrosion behaviour of superpure aluminium and aluminium-copper alloys were also considered using electronoptical, electrochemical and surface analytical probing. The influence that short and prolonged treatment times exert on the performances of such conversion coating is discussed. The conversion coating formed after 60 s and 180 s of immersion in the zirconium-based conversion coating bath provide good corrosion resistance which can be attributed to the high stability of the compounds that constitute the surface oxide layer, and good adhesion properties.
14
Kear, Gareth. "Electrochemical corrosion of marine alloys under flowing conditions". Thesis, University of Portsmouth, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369433.
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15
Akdeniz, Mahmut Vedat. "Rapid solidification of zinc based alloys". Thesis, Open University, 1989. http://oro.open.ac.uk/57270/.
Testo completoAbstract (sommario):
This work presents an investigation into two areas : the development of zinc based brazing alloys for the joining of copper produced by the rapid solidification technique; the study of the development of microstructures in rapidly solidified dilute zinc alloys. A new model has been proposed, based on the present experimental results and the available data from the literature, to account for the ribbon formation mechanism. Within this model ribbon formation in melt spinning is mainly determined by the behaviour of the viscosity in undercooled melts. It has been shown that, contrary to previous studies, the present model can be used to predict the ribbon thickness of both crystalline and amorphous alloys, and the agreement with the measured values is excellent. The development of microstructures in dilute zinc alloys during rapid solidification has been studied by the deliberate addition of impurity elements. Significant differences in structures are observed between the dilute zinc alloys and high purity zinc. The high purity zinc exhibits a strong preferred orientation with the basal plane parallel to the ribbon surface. The severity of this texture markedly reduces with the formation of cellular substructures in dilute zinc alloys. The morphology of the cells depends on the type of impurity elements present. The presence of impurity elements which expand on solidification leads to the development of an eutectic-like structure consisting of regular lamellae. This requires reorientation of the basal plane and instability of the solid liquid interface during solidification. The instability conditions of the planar solid liquid interface during rapid solidification of these alloys have been examined by using the morphological stability criterion. A possible mechanism which accounts for the formation of unusual structures observed in rapidly solidified dilute zinc alloys has been proposed. The observed variety of microstructures of binary Zn-Mg alloys, and the structural transitions across the ribbon thickness have been reported. Comparisons are made between as-cast and rapidly solidified materials and the resulting structures have been described using a growth rate composition map. Rapidly solidified eutectic and hypereutectic alloys show a tendency to form an amorphous phase. A total of more than 50 zinc based alloys have been investigated for the development of brazing filler metal. Alloys have been examined, and their compositions optimized, in terms of their spreading and wetting abilities and brazing performances to obtain a suitable candidate. Based on the experimental results it has been suggested that Zn-Mg alloys could be used for the joining of copper. They exhibit a lower surface tension, a lower density and comparable mechanical properties to high temperature high strength silver based brazing alloys.
16
Shepherd, Krupanand Solomon. "Diffusion Barriers/Adhesion Promoters. Surface and Interfacial Studies of Copper and Copper-Aluminum Alloys". Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2603/.
Testo completoAbstract (sommario):
The focus of this research is to study the interaction between copper and the diffusion barrier/adhesion promoter. The behavior of copper sputter-deposited onto sputter-cleaned tantalum nitride is investigated. The data show that copper growth on tantalum nitride proceeds with the formation of 3-D islands, indicating poor adhesion characteristics between copper and Ta0.4N. Post-annealing experiments indicate that copper will diffuse into Ta0.4N at 800 K. Although the data suggests that Ta0.4N is effective in preventing copper diffusion, copper's inability to wet Ta0.4N will render this barrier ineffective. The interaction of copper with oxidized tantalum silicon nitride (O/TaSiN) is characterized. The data indicate that initial copper depositions result in the formation a conformal ionic layer followed by Cu(0) formation in subsequent depositions. Post-deposition annealing experiments performed indicate that although diffusion does not occur for temperatures less than 800 K, copper "de-wetting" occurs for temperatures above 500 K. These results indicate that in conditions where the substrate has been oxidized facile de-wetting of copper may occur. The behavior of a sputter-deposited Cu0.6Al0.4 film with SiO2 (Cu0.6Al0.4/SiO2) is investigated. The data indicate that aluminum segregates to the SiO2 interface and becomes oxidized. For copper coverages less than ~ 0.31 ML (based on a Cu/O atomic ratio), only Cu(I) formation is observed. At higher coverages, Cu(0) is observed. These data are in contrast with the observed behavior of copper metal deposited onto SiO2 (Cu/SiO2). The data for Cu/SiO2 show that copper does not wet SiO2 and forms 3-D nuclei. Furthermore, post-annealing experiments performed on Cu0.6Al0.4/SiO2 show that neither de-wetting nor diffusion of copper occurs for temperatures up to 800 K, while Cu diffusion into SiO2 occurs ~ 600 K. These data indicate that aluminum alloyed with copper at the SiO2 interface serves as an effective adhesion promoter and thermal diffusion barrier.
17
鍾志源 e Chi-yuen Chung. "Recrystallization of cold rolled, direct-chill cast copper alloys". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31232565.
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18
Chung, Chi-yuen. "Recrystallization of cold rolled, direct-chill cast copper alloys /". [Hong Kong : University of Hong Kong], 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13212497.
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19
Subramaniam, Ameendraraj. "Fatigue behavior of copper zinc aluminum shape memory alloys". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0013/MQ32256.pdf.
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20
Brooks, Neal John. "The electronic and physical structure of copper palladium alloys". Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320609.
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21
Dungworth, David Barry. "Iron Age and Roman copper alloys from northern Britain". Thesis, Durham University, 1995. http://etheses.dur.ac.uk/1024/.
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22
Wu, Chang-Hong. "X-ray diffraction study of aged copper beryllium alloys". Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10022008-063043/.
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23
Elguindi, Jutta Ehlert. "Antimicrobial Efficacy of Copper Alloys in Changing Environmental Conditions". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202696.
Testo completoAbstract (sommario):
Copper cast alloys de-activate antibiotic-resistant bacteria on contact and could be very effective in decreasing potentially harmful microorganisms in the environment. In this study copper alloys with varying copper contents were utilized to evaluate their antimicrobial effects on Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecium in changing environmental conditions. The survival rates of P. aeruginosa wild type and its derivative transposon mutants of the cin operon on copper cast alloys were investigated in order to demonstrate the influence of genes involved in copper resistance. The gene disruption of the response regulator of the cin operon resulted in shorter survival rates on copper alloys, which was also influenced by temperature and method of exposure. Bacteria often have acquired copper resistance mechanisms in order to withstand higher copper concentrations in their surroundings, which may be a factor in their survival rates on copper surfaces. Copper- and antibiotic-resistant E. coli and E. faecium strains were obtained from pigs raised on feeds containing copper sulfate and antibiotics. Survival rates of these bacteria were influenced by the percentage of copper in the alloys, varying moisture conditions on copper surfaces, suspension media used, and differences between strains. Survival was also dependent on copper corrosion rates since corrosion inhibition with benzotriazole or a thick surface layer of thermal oxide resulted in prolonged survival on copper surfaces. Corrosion of copper surfaces releases copper ions which directly affect bacterial survival on copper alloys. The results obtained in this study emphasize that copper alloys are effective as antimicrobial materials but changing environmental conditions can significantly influence bacterial survival on copper surfaces. These findings can be applied to a better utilization of copper alloys in water, food, and healthcare environments. Antibiotic- and copper ion-resistant bacteria can be killed on contact with copper alloys which makes the proliferation of these microorganisms less likely and reduces the risk to human health. However, in a very different environment copper ion-resistant microbes can be useful for plant-microbe associations in bioremediation of copper mining wastelands.
24
Benedict, Michael Scott. "Heterogeneous nucleation of Sn in Sn-Ag-Cu solder joints". Diss., Online access via UMI:, 2007.
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25
Page, David Gordon. "Electrodeposition of thin film shape memory alloys". Thesis, University of Newcastle Upon Tyne, 2001. http://hdl.handle.net/10443/470.
Testo completoAbstract (sommario):
There is considerable potential for the use of thin film shape memory alloys in the field of microtechnology due to their high power to volume ratio. The main obstacles for fabrication arise mainly due to the narrow regime over which shape memory behaviour is observed and the paucity of process techniques. Shape memory transition in brass only occurs in the alloy composition range 38.5 - 41.6 wt %% zinc. This study used a pyrophosphate electrolyte containing Cu2P2O7, Zn2P2O7 salts and an excess of K4P207 and KNO3, for brass deposition as a replacement for cyanide electrolytes because it is non-toxic and noncorrosive. A rotating disc electrode was employed to systematically examine polarisation data and a rotating cylinder electrode was employed to produce thin brass films and deduce the current efficiencies of copper, zinc and brass deposition with respect to deposition potential. Thin films were plated between 5- 301im, they all displayed a smooth, uniform homogenous deposit with no precipitates or oxide inclusions. The current efficiencies were found to be < 45% for copper, < 15% for zinc and between 10 - 30% for brass. The microstructural characterisation of the Cu-Zn thin alloys was undertaken by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray fluorescence (EDAX), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). XRD showed all the electrodeposited Cu-Zn alloys to have same phase composition as those predicted by the equilibrium phase diagram for Cu-Zn. This confirmed the existence of the parent p-phase within the shape memory composition range, which undergoes the martensitic transformation. TEM showed these foils to be composed of a matrix of a, p and martensite nano sized grains (< 40nm) co-existing with a sparse distribution of larger grains (200-300nm). The larger grains were always martensite in nature, recognisable by their twinning planes. Differential scanning calorimetry analysis shows evidence of a martensitic transformation change for the thin brass films.
26
Barker, Simon William. "Diffusion induced liquid film migration in the aluminum-copper system /". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/NQ42721.pdf.
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27
Williams, J. R. "Corrosion of aluminium-copper-magnesium metal matrix composites". Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239852.
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28
Chiu, Chuang-Wei. "Catalytic conversion of glycerol to propylene glycol synthesis and technology assessment /". Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4421.
Testo completoAbstract (sommario):
Thesis (Ph.D.)--University of Missouri-Columbia, 2006.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 May 1, 2009) Vita. Includes bibliographical references.
29
Penegar, Ian. "Copper-nickel alloys in a marine environment : fouling and AFM studies of copper resistant bacteria". Thesis, University of Portsmouth, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326980.
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30
Akinlabi, Esther Titilayo. "Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper". Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1536.
Testo completoAbstract (sommario):
Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in 1991, for joining ferrous and non-ferrous materials1. The FSW of Aluminium and its alloys has been commercialised; and recent interest is focused on joining dissimilar materials. However, in order to commercialise the process, research studies are required to characterise and establish process windows. This research work through material characterisation of the welded joints establishes a process window for the Friction Stir welding of 5754 Aluminium Alloy and C11000 Copper. Furthermore, preliminary studies83,85 on the FSW of aluminium and copper have revealed the presence of intermetallic compounds which are detrimental to the weld qualities. This research work is also aimed at establishing process parameters that will result in limited or no intermetallic formation in the weld. The joint integrity of the resulting welds will also be correlated with the input process parameters. Based on the preliminary investigations conducted, a final weld matrix consisting of twenty seven welds was produced by varying the rotational speed between 600 and 1200 rpm, and the feed rate between 50 and 300 mm/min using three different shoulder diameter tools – 15, 18 and 25 mm to compare the heat input into the welds and to achieve the best results. The welds were characterised through microstructural evaluation, tensile testing, microhardness profiling, X-Ray Diffraction analysis, electrical resistivity and statistical analysis – in order to establish the interrelationship between the process parameters and the weld qualities. viii Microstructural evaluation of the weld samples revealed that the interfacial regions are characterised by mixture layers of aluminium and copper; while 33 percent of the tensile samples are within the acceptable range (> 75 percent joint efficiency). High Vickers microhardness values were measured at the joint interfaces, which corresponded with the intermetallic compounds. The Energy Dispersive Spectroscopy analysis revealed the presence of thin layers of intermetallics in nanoscale at the interfacial regions. The diffractograms of the X-Ray Diffraction analysis showed small peaks for intermetallics in some of the welds. Low electrical resistivities were measured at the joint interfaces. The statistical analysis showed that the downward vertical force, (Fz) can significantly influence the resulting weld qualities. An overall summary of the analysis of the weld qualities - with respect to the shoulder diameter tools employed showed that the 18 mm shoulder diameter tool is most appropriate among the three shoulder diameters considered, and a process window of medium spindle speed of 950 rpm and low-to-medium feed rate between 50 and 150 mm/min is established for FSW of Aluminium and Copper. Welds produced at 1200 rpm and 300 mm/min with low heat input did not have intermetallics formed at the joint interface.
31
Goldstein, Alexandra Susan. "Computer simulations of amorphous copper-zirconium /". Thesis, Connect to this title online; UW restricted, 1995. http://hdl.handle.net/1773/8629.
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Junk, Margrit. "Material properties of copper alloys containing arsenic, antimony, and bismuth". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-1299566.
Testo completoAbstract (sommario):
This work deals with Early Bronze Age ingot torques, their composition, and material properties. The aim was to decide whether and how a choice of materials by composition or properties was possible during the Early Bronze Age. Early Bronze Age ingot torques were analysed and artefacts from several hoard finds and working stages were investigated metallographically. On the basis of these data the production technology was reconstructed. For the determination of mechanical and technological properties, reference alloys were produced and investigated. The production process was simulated by forging experiments. The investigations revealed that ingot torques were produced by a standardised technology, independent of their composition. The results of the material testing show that it is possible to distinguish the composition of the Early Bronze Age alloys by their mechanical and technological properties.
33
Khalid, Fazal Ahmad. "Precipitation of microalloying elements and copper in steels and alloys". Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303007.
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Forslund, Mattias. "Micro-galvanic effects and corrosion inhibition of copper-zinc alloys". Doctoral thesis, KTH, Yt- och korrosionsvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-151189.
Testo completoAbstract (sommario):
With the advancement and accessibility of local probing techniques that can operate at the submicron scale it has become possible to analyse the local corrosion properties of industrially important metallic materials and relate these properties to microstructure characteristics of the same materials. In this doctoral study the focus has been on copper-zinc samples, both as industrial brass alloys and as micro-patterned copper-zinc samples. They have been exposed to dilute chloride solutions and to an atmosphere that mimics indoor conditions that cause corrosion. The main goal has been to investigate micro-galvanic effects caused by surface heterogeneities in the copper-zinc samples, and the corrosion inhibition ability of a self-assembled octadecanethiol (ODT, CH3(CH2)17SH) monolayer when applied to these heterogeneous samples. The local chemistry, local electrochemistry, and local surface chemistry in the presence of the copper-zinc galvanic couplings have been elucidated, and their importance has been investigated for corrosion initiation, propagation, termination, and inhibition. A broad spectrum of local probe techniques has been utilised. They include optical microscopy (ex situ and in situ), electrochemical techniques, scanning electron microscopy with energy dispersive spectroscopy, atomic force microscopy, scanning Kelvin probe force microscopy and confocal Raman spectroscopy. In addition, infrared reflection absorption spectroscopy (in situ) and vibrational sum frequency spectroscopy have been employed to analyse the formation of corrosion products and monitor the corrosion kinetics. A characteristic selective zinc dissolution process was triggered in non-metallic inclusions when a brass alloy was exposed to 1 mM NaCl. Disc-like corrosion areas spread radially outwards from the inclusions, the shape and termination of which was attributed to accessibility to chloride ions. An ODT-layer deposited on brass retarded access to chloride ions at the brass surface and slowed down the radial corrosion process. Instead a delayed formation of filiform-like corrosion was observed. Upon exposure of the copper-zinc patterned sample to humidified air containing formic acid, micro-galvanic effects were induced by the copper patches on zinc that accelerated the zinc dissolution in the thin aqueous adlayer with concomitant precipitation of zinc formate. The micro-galvanic effects not only resulted in accelerated corrosion rates for zinc, but also in broadening of shapes and atomic structures for the corrosion products formed. Crystalline zinc oxide and zinc formate were observed on the copper-zinc patterned samples, whereas amorphous zinc oxide and zinc formate were formed on the bare zinc surface. Micro-galvanic effects occurred in the two-phase Cu40Zn (Cu with 40 wt% Zn) brass alloy as well, induced by more zinc-rich beta-phase grains surrounded by an alpha matrix with lower zinc-content. The application of a self-assembled monolayer of ODT for corrosion inhibition of pure zinc and the patterned copper-zinc samples was also explored. In situ infrared reflection absorption spectroscopy analyses showed that ODT initially reduced the rate of zinc formate formation on pure zinc and on the copper-zinc micro-patterned sample. However, the inhibition efficiency was slightly reduced with exposure time due to local removal of ODT on pure zinc and on the micro-patterned samples. This caused micro-galvanic effects that resulted in increased rates of zinc formate formation on the ODT-covered samples – even higher than on the uncovered samples. When applied to the single-phase Cu20Zn alloy, ODT resulted in a corrosion inhibition that was comparable to that of pure copper, a metal for which ODT has shown very good corrosion inhibition. On double-phase Cu40Zn local galvanic effects resulted in less efficient corrosion inhibition and more abundant corrosion products than on Cu20Zn. Based on vibrational sum frequency spectroscopy, the ODT-layer retained its well-ordered molecular structure throughout the exposure to both Cu20Zn and Cu40Zn. In all, the inhibiting action of the ODT-layer was attributed to the transport hindrance of corrosion promoters (O2, H2O, and HCOOH) to the brass surface. This result suggests that ODT can function as a temporary corrosion inhibitor for brass exposed to benign indoor environments.Med utvecklingen av och tillgången till lokala analysmetoder som kan ge information med en lateral upplösning på mindre än en mikrometer har det blivit möjligt att analysera lokala korrosionsegenskaper hos industriellt viktiga metalliska material och relatera dessa egenskaper till mikrostrukturen hos samma material. I doktorsavhandlingen har denna möjlighet utnyttjats för koppar-zinkprover, dels som industriella mässingslegeringar dels som mikro-mönstrade koppar-zinkprover, som exponerats för utspädda kloridlösningar samt för en atmosfär som kan efterlikna den atmosfäriska korrosionen inomhus. Det huvudsakliga målet har varit att undersöka dels mikro-galvaniska korrosionseffekter som orsakas av heterogeniteter på koppar-zinkytorna dels korrosionsförmågan hos självorganiserande monolager av oktadekantiol (ODT, CH3(CH2)17SH) vid adsorption på dessa heterogena ytor. På så vis har den lokala kemin, ytkemin och elektrokemin kunnat klarläggas i närvaro av galvaniska effekter, och dess betydelse har undersökts för korrosionsprocessens initiering, propagering, terminering och inhibering. Ett brett spektrum av lokala analysmetoder har utnyttjats. De innefattar ljusoptisk mikroskopi (ex situ och in situ), elektrokemiska metoder, svepelektronmikroskopi med energidispersiv röntgen-spektroskopi, atomkraftsmikroskopi för mikro-kartering och Voltapotentialmätningar samt konfokal Raman-spektroskopi. Dessutom har infrarödreflektions absorptionsspektroskopi (in situ) och vibrationssummafrekvens spektroskopi (engelska: vibrational sum frequency generation) använts. När en mässingslegering exponerades för 1 mM NaCl observerades en selektiv utlösning av zink med karakteristiskt utseende som växte radiellt från icke-metalliska inneslutningar för att bilda cirkulärt formade korrosionsområden. Formen och termineringen av denna korrosionsprocess bestäms av tillgången på kloridjoner. När ett monolager av ODT adsorberades på mässingslegeringen hämmades tillgången av kloridjoner på mässingsytan och den radiella korrosionsprocessen stannade upp. Istället iakttogs en fördröjd bildning av s.k. filiform korrosion. Vid exponering av mikro-mönstrade koppar-zinkprover för befuktad luft med låga tillsatser av myrsyra inducerades mikro-galvaniska effekter i gränsen mellan koppar och zink som accelererade utlösningen av zink i den adsorberade fuktfilmen på provet, under samtidig utfällning av zinkformat. De mikro-galvaniska effekterna resulterade inte bara i förhöjda korrosionshastigheter jämfört med de på ren zink, utan även i andra faser hos bildade korrosionsprodukter. På de mikro-mönstrade koppar-zinkproverna bildades kristallint zinkoxid och zinkformat, under det att amorft zinkoxid och zinkhydroxyformat bildades på ren zink. Mikrogalvaniska effekter observerades även i den tvåfasiga mässingslegeringen Cu40Zn (Cu med 40 vikt-% Zn) orsakade av kontakten mellan den mer zinkrika beta-fasen och den omgivande alfa-fasen med lägre zinkhalt. Appliceringen av ett självorganiserat monolager av ODT för korrosionsinhibering av ren zink och koppar-zinkprover har också undersöks. In situ infrarödreflektions absorptionsspektroskopi visade att adsorberat ODT initialt hämmade bildningen av zinkformat på ren zink och på de mikro-mönstrade koppar-zinkproverna. Med tiden minskade ODTs korrosionsinhiberings-förmåga på grund av att ODTs vidhäftning lokalt försvann. De mikro-galvaniska effekter som därigenom uppstod resulterade i bildandet av zinkformat som med tiden blev snabbare på de ODT-belagda proverna än på motsvarande prover utan ODT. När ODT applicerades på den enfasiga mässingslegeringen Cu20Zn resulterade detta i en korrosionsinhibering som var jämförbar med den på ren koppar, en metall på vilken ODT tidigare visat mycket bra korrosionsskydd. På den tvåfasiga mässingslegeringen Cu40Zn ledde lokala galvaniska effekter till en mindre effektiv korrosions-inhibering och en rikligare mängd korrosionsprodukter än på Cu20Zn. Baserat på vibrationssummafrekvens spektroskopi behöll ODT-lagret dess välordnade struktur under hela exponeringen på både Cu20Zn och Cu40Zn. ODTs korrosionsinhibering tillskrivs främst transport-hämningen av korrosionsstimulatorer (O2, H2O och HCOOH) till mässingsytan och antyder att ODT kan fungera som en temporär korrosionsinhibitor för mässing i milda inomhusmiljöer.
QC 20140915
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Harsacky, Frank J. Jr. "Processing studies of aluminum-magnesium and aluminum-copper-lithium alloys". Thesis, Monterey, California: Naval Postgraduate School, 1990. http://hdl.handle.net/10945/34850.
Testo completoAbstract (sommario):
Approved for public release; distribution is unlimited.Investigation into the effect on superplastic behavior of two aluminum alloys produced by variations of thermomechanical processing parameters was conducted. The alloys in this study are Al-10Mg-0.1Zr (weight percent) and 2090, which is Al-2.56Cu-2.03Li-0.12Zr (weight percent). Determination of the existence of an optimum balance between deformation and recovery for the Al-10Mg-0.1Zr alloy was accomplished by extending the annealing interval to 60 minutes during warm rolling at 300 C. The optimum balance is a 30 minute annealing interval between rolling passes. Processing of Al-10Mg-0.1Zr with a rolling temperature lower than the annealing temperature produced ductilities which are less than those obtained by utilization of the optimum process. The extension of annealing intervals in the processing of 2090 resulted in increased superplastic response when compared with results obtained employing shorter annealing intervals. By application of a two-temperature process which incorporates rolling at a lower temperature than the annealing temperature, the determination has been made that enhanced ductility results however, the annealing interval of 14 minutes should be extended.
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De, Bono Paola. "Laser welding of copper and aluminium alloys for electrical interconnects". Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6898/.
Testo completoAbstract (sommario):
The adoption of lithium-ion and/or super-capacitor battery technologies is a current hot topic in the automotive industry. For both battery types, the terminals and busbars are manufactured from copper (Cu) and/or aluminium-based (Al-based) alloys, as a result of their high electrical and thermal conductivities. Laser welding is considered an attractive process to industry due to its easy auto-motability, high processing speed and highly repeatable cost-effective processing. However, laser welding of monometallic and dissimilar Cu and A1 presents several difficulties due to the high surface reflectivity at infrared (IR.) wavelengths. Three main areas were investigated in this research work: • Laser beam lap-welding of monometallic Cu sheets, with the aim of validating the developed welding procedures against target specifications addressed by the automotive industry, in line with production environment setups. • The suitability of using tailored energy distributions, produced using a 1070nm laser source delivered through a laser beam scanner, for welding multiple overlapping Al or Cu foils. • The effects of different laser processing parameters on the formation of deleterious brittle intermetallic phases when welding Alto Cu with a continuous-wave Yb-fibre laser.
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Low, C. T. John. "Rotating electrodes : the electrodeposition of tin and tin-copper alloys". Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/195955/.
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Touzé, Stéphane. "Laser Metal Deposition of Aluminium-Copper alloys for Repair applications". Thesis, Ecole centrale de Nantes, 2019. http://www.theses.fr/2019ECDN0025.
Testo completoAbstract (sommario):
Ce travail de thèse vise à démontrer la faisabilité de la réparation de pièces de fonderie à haute performance et haute valeur ajoutée faites d’un alliage aluminiumcuivre en utilisant un procédé de fabrication additive métallique par projection de poudre avec fusion laser dénommé Laser Metal Deposition. Ces alliages présentent notamment une faible soudabilité et ne peuvent donc être réparés de façon fiable par des procédés traditionnels de soudage à l’arc. Afin de permettre l’utilisation de ce procédé innovant pour la réparation de pièces en alliage Al-Cu, des difficultés majeures ont dû être levées en ce qui concerne notamment la coulabilité des poudres Al-Cu et leur comportement en fusion et en solidification, ainsi que la méthodologie de réparation pour effectuer l’opération de façon fiable et efficace. Des travaux expérimentaux, théoriques et numériques ont permis d’élucider ces aspects et in fine de permettre l’utilisation de ce matériau avec ce procédé de fabrication additive. Une méthode de réparation comprenant un algorithme de segmentation robuste a également été développée et mise en oeuvre afin d’automatiser le processus de réparation en permettant la génération de trajectoire sur la base de mesures 3D in-situ. Des réparations de pièces de fonderie en aluminium-cuivre ont ainsi pu être effectuées avec le procédé Laser Metal Deposition, et les analyses métallographiques montrent que les rechargements effectués avec ce procédé offrent une microstructure très fine avec un taux de ségrégation chimique limité et peu de fissuration à chaudThe present thesis aims at demonstrating the feasibility of repairing high performance castings made of an aluminiumcopper alloy using the Laser Metal Deposition metal additive manufacturing process. These alloys present a low weldability and thus cannot be reliably repaired with manual arc-welding processes. To instead use this innovative additive manufacturing process for repair applications and thereby improve upon current methods, major challenges had to be overcome regarding the flowability and solidification behavior of this aluminium alloy powder as well as the overall methodology to reliably and efficiently perform the repair operation. Experimental, theoretical and numerical studies allowed to elucidate some of these aspects and eventually enabled the use of a 224.0 casting aluminium alloy with the Laser Metal Deposition metal additive manufacturing process. A repair methodology including a robust segmentation algorithm was also developped to automate the repair process and permit the generation of toolpaths based on raw in-situ 3D scanning measurements. Repairs of high performance aluminium-copper castings were carried out successfully as no major lack of fusion, bonding or cracking defects were observed. A metallographic analysis showed that the aluminium deposits obtained by Laser Metal Deposition generally offer a refined microstructure with limited solute segregation and hot cracking
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Ocansey, Paul Morgan-Narteh. "Nucleation and early growth during solidification of aluminum-copper alloys". Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187082.
Testo completoAbstract (sommario):
Using a relatively simple experimental setup, thermal history, microstructural evolution, nucleation, and early growth during solidification of aluminum-copper alloys are investigated. In particular, nucleation rates are measured, and contact angles calculated using the classical heterogeneous nucleation theory. Also, growth velocities of the dendrites are measured and compared with those predicted using kinetic models in order to elucidate which model is controlling during recalescence or early growth. Two groups of aluminum alloys with 5.1, 6.6, 15.6, and 30 wt% Cu are studied. One group is uninoculated and the other is grain refined with Ti-B-Al, Ti-B, and Ti-C-Al master alloys. In alloys that exhibit recalescence of primary solid, solidification occurs at a temperature, approximately 0.4 °C or less before the minimum in the curve is reached. Grain refined alloys exhibit dendrites which are equiaxed in morphology and appear as clusters in a matrix of quenched liquid. Uninoculated alloys, however, contain somewhat columnar dendrites. Nucleation rates are composition sensitive and range from 4.8 x 10¹³ m³/s to 1.6 x 10\sp¹⁵ m³/s in uninoculated alloys; with an increase in copper content there is an increase in nucleation rate. In grain refined alloys, the same metric measures from 4.4 x 10¹⁶ m³/s to 1.4 x 10¹⁹ m³/s. The calculated contact angles are consistently smaller in the grain refined alloys when compared with their uninoculated counterparts and are rather sensitive to small changes in the measured undercooling. For example, if the undercooling with respect to the liquidus temperature is known to within ± 1°, the calculated contact angle changes by ± 0.8°. Experimental growth rates in grain refined alloys are less than in uninoculated alloys, because the undercoolings during the early stages of growth are less. While growth rate in uninoculated alloys typically range from 2.2 x 10⁻⁴ m/s in the most concentrated alloy to 1.8 x 10⁻³ m/s in the most dilute alloy, the same metric in grain refined alloys ranges from 7.8 x 10⁻⁵ m/s to 1.7 x 10⁻⁴ m/s. Experimental growth rates compare favorably to dendrite growth models of Ivantsov, and Lipton-Glicksman-Kurz. Consequently, during recalescence and/or early growth, the growth velocity of primary solid is controlled by solute diffusion processes and not by interface kinetics.
40
Nemeth, Bill. "Casting conditions and iron variant effects on the subsequent nucleation of Al₂₀Cu₂Mn₃ dispersoid phase in Al-4Cu-0.4Mn-0.2Si alloys". Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/20805.
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McCusker, Niall. "Deposition and characterisation of copper for high density interconnects". Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314085.
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Totty, Jennifer L. "Linear cellular copper in bending, compression and shear". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/16913.
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Jonnalagadda, Krishna Praveen. "Influence of Graphite type on copper diffusion in P/M copper steels". Thesis, KTH, Materialens processteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98264.
Testo completoAbstract (sommario):
One main reason for the use of Fe-Cu-C system in PM industry is the presence of liquid phase (copper) at the start of sintering (1120oC). The diffusion of liquid copper into iron causes swelling in the structure. This in turn can cause high dimensional change and, if not controlled properly, may cause distortion. So it is of paramount importance to control the copper diffusion. Carbon, added as graphite, reduces the swelling of copper by changing the dihedral angle. The affect of graphite on copper diffusion depends on the graphite type, particle size of graphite and heating rate. The aim of this work was to find the influence of graphite type and particle size of graphite on copper diffusion. Water Atomized iron (ASC100.29) produced in Höganäs AB was taken as the base powder. Two types of graphite were used each with two different particle sizes. Two different graphite quantities (0.2% & 0.8%) for each type was taken. Natural fine graphite (UF4), Natural coarse graphite (PG44), Synthetic fine graphite (F10) and Synthetic coarse graphite (KS44) were the graphites used in this work. Powders were compacted at 600 Mpa and the sintering was done at 1120oC for 30 minutes in 90/10 N2/H2. Dilatometry and metallographic investigation of the samples sintered in the production furnace were used to understand the graphite influence. The investigation showed that at low graphite levels (0.2%), the affect of graphite type or graphite size was not significant on copper diffusion. At high graphite levels (0.8%), synthetic graphites were more effective in reducing the swelling of copper. Influence of particle size of synthetic graphites on Cu diffusion was not significant compared to the influence of particle size of natural graphite. There was also a considerable affect of heating rate on graphite dissolution and copper swelling.
44
Monaghan, Dermot. "High rate unbalanced magnetron sputtering of thick films of ultra-fine brained OFHC copper and copper alloys". Thesis, University of Salford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336163.
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Hsu, Yiu-Kang. "Dynamic flows of copper and copper alloys across the prehistoric Eurasian steppe from 2000 to 300 BCE". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:e6e7b95e-b852-4e38-8793-76d817149ce9.
Testo completoAbstract (sommario):
The study of ancient Eurasian metallurgy has been suffering from (or preoccupied by) two conventional perspectives. One is that of the diffusion model emphasising the importance of the settled empires of ancient Egypt and Mesopotamia, of south-eastern Europe and of China (Shennan 1986, 1993; Kristiansen 1984). The supremacy of these 'cradles' of early civilisation is marked not only by social hierarchies, but also by technological inventions such as metal production. This view sees the mobile populations of the Eurasian steppe as occupying the "hinterland" of these early settled states in the south, believing that the emergence of metal technologies in the Steppe was the result of the expansions of "advanced" civilisations. The second perspective is rooted in the provenance study which traces metal objects back to their geological sources (Pernicka 2014). It assumes that chemical and isotopic composition of metal is static and only reflects a simple linear relationship between artefacts and specific ore deposits. Drawing from a legacy database of approximately 9,000 chemical analyses of copper-based artefacts, this thesis rejects the simplicity of both the diffusion and the provenance models. While admitting that the use of metal might have originated from western Asia, the development of metallurgy in the Eurasian steppe should be understood on its own terms. It is constantly re-shaped by vigorous circulation of metal artefacts across mobile communities on a regional or inter-regional scale. This observation is based on the application of a new innovative framework to interpret the patterns of compositional data (Bray et al. 2015). This novel method argues that metal can flow, quite literally, from one object to another as it is re-melted, re-mixed and re-cast in different shapes and colours, depending on different social contexts. Thermodynamic modelling and modern experiments have shown that during the copper melt, some volatile elements in copper alloys (e.g. arsenic, antimony, and zinc) are preferentially removed through oxidative loss. Instead, some elements, such as silver, nickel, and gold, tend to be preserved in metals. These predictable patterns of elemental losses provide valuable information to trace the directional flow of metal units between regions/cultures, if we combine chemical data of metal artefacts properly with archaeological context, landscape and chronology. By using this new methodology, several routes of copper supplies have been identified in the Steppe during different periods. They feature the exchange of metals within regional networks, fuelled by local copper sources. The Urals, central Kazakhstan, the Altai, and the Minusinsk-Tuva regions were the primary copper production centres that developed distinct trace-element chemistry and artefact typology. By contrast, alloying techniques employed by steppe peoples, generally demonstrate the long-distance connections based on two major metallurgical practices: arsenical copper in the western steppe and tin-bronze in the eastern steppe. Copper-arsenic production was concentrated in the Caucasus but the recycling of its arsenical copper became more apparent further away towards the Urals. On the other hand, the invention of tin-bronze metallurgy was triggered by the formation of the Seima-Turbino phenomenon (c. 2100- 1800/1700 BC) in the Altai, and this alloying tradition was amplified by the emergence of the Andronovo culture (c. 1700-1400 BC) in the Ural-Kazakh steppe. Tin-bronze ornaments, in particular, were exchanged between eastern and western mobile communities over a considerable distance, through the mechanism of pastoral seasonal movements. In conclusion, traditional views of diffusion and provenance theories cannot be uncritically applied to the inception of ancient metallurgy in the Eurasian steppe. Mobile pastoralists developed multi-regional production hubs based on the accessibility of ore resources and the variations in subsistence strategies. Although steppe metalwork revealed some technological borrowings from settled communities, steppe peoples had transformed them into locally adapted products that could fit into their socio-economic systems. That is, when dealing with the issues of Eurasian metallurgy, we should acknowledge the complexity of human engagement with metal and look into subtler differences in cultural context, landscape, and ideology.
46
Lamport, Robert Anthony. "Defect characterization in binary aluminum-copper alloys by position annihilation spectroscopy". Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/19918.
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Kam, Weng Seng. "Laser surface alloying of copper with Ni-based hardfacing alloys for enhancing hardness and corrosion resistance". Thesis, University of Macau, 2017. http://umaclib3.umac.mo/record=b3691686.
Testo completo
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Nielsen, Øyvind. "Mushy zone permeability and grain morphology in equiaxed aluminium-copper alloys". Doctoral thesis, Norwegian University of Science and Technology, Department of Materials Technology, 2000. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1486.
Testo completo
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Nicol, Alison. "Aspects of copper precipitation and irradiation hardening in Fe-Cu alloys". Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325841.
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Watson, Neil John. "Corrosion studies of 70/30 copper/nickel alloys in sea water". Thesis, University of Brighton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290480.
Testo completo