Ionometallurgy is a new trend to utilise ionic liquids as alternative green solvents for oxidic and sulfidic copper minerals. It has broad potential for traditional pyrometallurgy and hydrometallurgy. Ionometallurgy utilises ionic liquids (ILs), highly potent complexing ligands (chloride), to process oxide and copper sulfide minerals. This work focused on using the deep eutectic solvents (DES) of ionic liquids, which and provide alternative options for processing various metals, alloys, and concentrates. For this job, various analytical methods were used to determine the copper concentrate and its residue after leaching (MLA-SEM and XRPD), quantify the elements in the solution (IC and ICP-OES/MS) and explain the oxidation behaviour (CV and UV-Vis spectroscopy). Combining the analytical and electrochemical methods to the leaching experiment provided the control to improve the results and understand its oxidation behaviour. Chosen DES, Oxaline (ChCl + oxalic acid, 1:1), and Ethaline (ChCl + ethylene glycol, 1:2) were tested and enhanced on the actual copper concentrates with and without oxidative additives (FeCl3 and I2). Those oxidative additives are selected for leaching experiments by their redox potential in Ethaline. However, there are many acceptable values; the most exciting result related to Ethaline plus iodine was the potential leaching system for chalcopyrite and copper-gold concentrates leaching. Because ion chromatography (IC) and UV-Vis’s analysis confirm iodine oxidizes the Cu+ species quickly in Ethaline. Whilst identical results and oxidation behaviour appeared in chalcocite (Cu2S), chalcopyrite (CuFeS2) and copper-gold concentrates leaching. During the iodine reduction to iodide in the system, IC proved that chalcopyrite releases the Fe3+, oxidizing the chalcopyrite particles. Also, iodine oxidized the natural gold in copper-gold concentrate successfully, and gold concentration quantified ICP-MS and MLA-SEM proved there is no visible gold in the leaching residue. Based on the optimal Ethaline + I2 leaching condition, the copper concentrate was carried out with the bottle roller leaching to represent the tank leaching. Thus, DES shows that it has a high potential to be continued to scale up the experiment. Also, water was given to the Ethaline leaching system, and water had a good influence on the leaching due to reducing the viscosity and saving the Ethaline amount. Hence Ethaline plus water is used for the copper ore leaching in the column, and it can be seen that Ethaline + I2 with water (up to 20%) has a high potential to process the low-grade copper sulfide ores.:Acknowledgements Abstract Abbreviations TABLE OF CONTENTS CHAPTER ONE – INTRODUCTION OF COPPER PROCESSING TECHNOLOGIES 1.1. Overview 1.2. Copper 1.3. Gold 1.4. Hydrometallurgy and pyrometallurgy of copper and gold 1.5. Current copper and gold concentrate processing methods 1.6. An alternative copper concentrate processing method Summary of chapter 1 CHAPTER TWO – FUNDAMENTALS FOR PROCESS DEVELOPING 2.1. Introduction 2.2. Effect of temperature and stirring in leaching 2.3. Analytical methods and experimental 2.4. Experimental for leaching 2.5. Discussion of experimental errors CHAPTER THREE: ANALYTICAL EXPERIMENTS FOR LEACHING 3.1. Introduction 3.2. Analysis of copper concentrate 3.3. Cyclic voltammetry 3.4. UV-Vis spectroscopy analysis of target metals 3.5. Metals solubility in DES 3.6. Summary and conclusions CHAPTER FOUR: FUNDAMENTAL LEACHING EXPERIMENT AND INITIAL INVESTIGATION 4.1. Introduction 4.2. Initial study and fundamental leaching experiments 4.3. Study of mineral oxidation 4.4. Deep eutectic solvents leaching 4.5. Chapter summary and conclusion CHAPTER FIVE: LEACHING OF MODEL SYSTEMS IN ETHALINE WITH OXIDATIVE ADDITIVES 5.1. Introduction 5.2. Iodine effect on Cu2S and CuS leaching in Ethaline 5.3. Ferric chloride effect on CuS and Cu2S leaching 5.4. Leaching of natural gold in Ethaline with the presence of iodine 5.5. Cyclic voltammetry investigation of Cu+/2+ sulfides in DES 5.6. Chapter summary and conclusion CHAPTER SIX: LEACHING OF COPPER-GOLD CONCENTRATES IN DES AND WITH OXIDATIVE ADDITIVES 6.1. Introduction 6.2. Effect of ferric chloride (FeCl3) 6.3. Effect of iodine (I2) 6.4. Electrochemical and spectroscopic analysis of copper-gold concentrate leachates 6.6. Chapter summary and conclusion CHAPTER SEVEN: OVERALL CONCLUSION AND FUTURE WORK 7.1. Overall conclusions 7.2. Recommendations for future research CHAPTER EIGHT: APPENDIX 8.1. Chemicals and materials 8.2. Appendix References

This thesis presents methods for the wafer-level integration of shape memory alloy (SMA) and electrostatic actuators to functionalize MEMS devices. The integration methods are based on heterogeneous integration, which is the integration of different materials and technologies. Background information about the actuators and the integration method is provided. SMA microactuators offer the highest work density of all MEMS actuators, however, they are not yet a standard MEMS material, partially due to the lack of proper wafer-level integration methods. This thesis presents methods for the wafer-level heterogeneous integration of bulk SMA sheets and wires with silicon microstructures. First concepts and experiments are presented for integrating SMA actuators with knife gate microvalves, which are introduced in this thesis. These microvalves feature a gate moving out-of-plane to regulate a gas flow and first measurements indicate outstanding pneumatic performance in relation to the consumed silicon footprint area. This part of the work also includes a novel technique for the footprint and thickness independent selective release of Au-Si eutectically bonded microstructures based on localized electrochemical etching. Electrostatic actuators are presented to functionalize MEMS crossbar switches, which are intended for the automated reconfiguration of copper-wire telecommunication networks and must allow to interconnect a number of input lines to a number of output lines in any combination desired. Following the concepts of heterogeneous integration, the device is divided into two parts which are fabricated separately and then assembled. One part contains an array of double-pole single-throw S-shaped actuator MEMS switches. The other part contains a signal line routing network which is interconnected by the switches after assembly of the two parts. The assembly is based on patterned adhesive wafer bonding and results in wafer-level encapsulation of the switch array. During operation, the switches in these arrays must be individually addressable. Instead of controlling each element with individual control lines, this thesis investigates a row/column addressing scheme to individually pull in or pull out single electrostatic actuators in the array with maximum operational reliability, determined by the statistical parameters of the pull-in and pull-out characteristics of the actuators. / QC20100729

Much study has been carried out to determine the properties of Lamellar Graphite Iron (LGI) or grey iron and their relations to factors such as the cooling rate, the dendrite morphology, the pouring temperature, and so on. However, there hasn’t been much comprehensive study on the properties of LGI outside the generally used and accepted composition, with 1 to 3% Silicon. The scope of this study is to measure and evaluate the thermal conductivity and tensile strength of LGI, for a higher concentration of  Si and different carbon contents. The concentration of Si aimed for was 4% but the concentration obtained after spectroscopy was between 4.1% to 4.15%. There are two hypereutectic, one near-eutectic and three hypoeutectic samples considered and these six chemical compositions were cast under different cooling conditions . The cooling time has been varied by providing different molds of 30mm, 55mm, and 80mm diameter cylinders respectively, for all the six sample compositions. The microstructure analysis carried out studies the segregation of Si, the graphite morphology, primary austenite morphology. These factors are then compared to the thermal and tensile behavior measured in this study. It can be observed that the thermal conductivity studied in the present work has a direct correlation for a higher Si content and tends to be greater than the thermal conductivity values observed from other studies with lower content Of Si. However, the conductivity shows an inverse relation with the cooling rate and is maximum for the samples with the lowest cooling rate. The tensile strength, on the other hand, seems to have a lower value than that observed in previous studies for LGI with 1 to 3% Si, but shows a direct correlation with the cooling rate. The mean area fraction of dendrites obtained and the mean interdendritic hydraulic diameter is also measured and their influence on the properties are also studied. The addition of more Si has greatly favored the thermal behavior positively but has also reduced the tensile strength.

Настоящая работа состоит из 3 глав и посвящена бесферментному количественному определению креатинина, глюкозы, мочевины с использованием медь(II)-имидазольных каркасов. В ходе работы проведено формирование электрокаталитически активного слоя на поверхности рабочего электрода. Таким образом, каталитически активный слой с наибольшей чувствительностью сформирован на печатном электроде 3-в-1 с использованием многостенных углеродных нанотрубок (cMWCNT), электроосаждённым золотом и медь(II)-имидазольного каркаса, состоящего из иона меди(II) и 2-меркаптоимидазола и 2-метилимидазола. Проведены исследования селективности полученного каталитически активного слоя. / This work consists of 3 chapters and is devoted to the enzyme-free quantitative determination of creatinine, glucose, urea using copper(II)-imidazole frameworks. In the course of the work, the formation of an electrocatalytically active layer on the surface of the working electrode was carried out. Thus, the catalytically active layer with the highest sensitivity is formed on a 3-in-1 printed electrode using multi-walled carbon nanotubes (cMWCNT) electrodeposited with gold and copper(II)-imidazole framework consisting of copper(II) ion and 2-mercaptoimidazole and 2-methylimidazole. The selectivity of the obtained catalytically active layer has been studied.

[ES] Esta Tesis Doctoral se centra en la recuperación mediante electrodeposición del Sb presente en un efluente residual proveniente de la metalurgia del cobre. El efluente en el que se basa este estudio se produce en el proceso de regeneración con HCl concentrado de las resinas de intercambio iónico de una de las subetapas del electro-refinado del cobre. Se trata de un electrolito ácido que contiene diversas impurezas, entre las que destacan, Sb y Bi, que son considerados materias primas críticas por la Unión Europea, debido al riesgo de suministro que presentan y a su importancia en la economía. El objetivo de esta Tesis es la recuperación del Sb y la reutilización del HCl. Para alcanzar ambos propósitos se ha estudiado el empleo de la electrodeposición como operación de separación para el tratamiento del efluente. Este proceso se ha investigado mediante técnicas electroquímicas, en particular, voltametría cíclica y de barrido lineal. En primer lugar, se ha realizado el estudio con disoluciones sintéticas que emulan el efluente generado en las metalurgias chilenas. La caracterización electroquímica de la disolución de Sb en medio HCl ha evidenciado que la reducción del Sb(III) a Sb metálico está limitada por la transferencia de materia y que una concentración elevada de HCl favorece la recuperación del Sb. Los ensayos de electrodeposición han destacado la relevancia de las reacciones secundarias, la reacción de evolución del hidrógeno (HER) y la generación de cloro, y su influencia negativa sobre la deposición de Sb. La HER tiene lugar en el cátodo y conlleva la generación de burbujas de hidrógeno a elevadas densidades de corriente, que reducen la superficie útil del electrodo de trabajo e incluso causan el desprendimiento del depósito de Sb. Por su parte, la generación de cloro gas en el ánodo provoca la redisolución de los depósitos de Sb desprendidos a causa de la HER. Tras la realización de estos ensayos se ha concluido que se puede aumentar la tasa de recuperación de Sb si se tienen mayores concentraciones del elemento en la disolución o si se mejoran las condiciones hidrodinámicas. Se ha analizado también cómo influye la presencia de Bi en la disolución sintética durante la electrodeposición del Sb. El potencial de reducción de ambos elementos es similar, lo que implica que la recuperación individual de Sb sea compleja. No obstante, si se trabaja bajo condiciones en las que no se supere la densidad de corriente límite del sistema, se logra una elevada selectividad hacia el Sb. Si la concentración de Bi en la disolución es superior a la de Sb, se electrodepositan ambos elementos, pero se logra un elevado valor de eficiencia de corriente debido a que la influencia de la HER sobre el Bi no es tan fuerte. A continuación, se ha estudiado la aplicación de las técnicas previamente analizadas con un efluente real, facilitado por una empresa española. Se ha verificado que las conclusiones obtenidas con las disoluciones sintéticas son aplicables al efluente real. En particular, se ha confirmado que, al aumentar la densidad de corriente aplicada, la deposición de Sb se ve mermada debido a la relevancia del resto de reacciones: la reducción de los demás elementos y la evolución del medio. Los depósitos obtenidos contienen algunos de los elementos presentes en el efluente real: Sb, Bi, As y Cu, siendo mayoritario el primero. Como resultado, se ha concluido que es posible purificar el HCl mediante la electrodeposición de los elementos contenidos en el electrolito. Finalmente, se ha planteado la posibilidad de sustituir el HCl empleado como regenerante por un disolvente eutéctico profundo, debido a la alta solubilidad de metales y su procedencia de fuentes renovables. En particular, la investigación se ha llevado a cabo con la oxalina, la cual presenta una elevada capacidad de disolución para el Sb y una amplia ventana de potencial que beneficiaría la aplicación de la técnica de electrodeposición para la recuperación del Sb. / [CA] Esta Tesi Doctoral se centra en la recuperació mitjançant electrodeposició del Sb present en un efluent residual provinent de la metal·lúrgia del coure. L'efluent en què es basa este estudi es produïx en el procés de regeneració amb HCl concentrat de les resines d'intercanvi iònic d'una de les subetapes de l'electro-refinat del coure. Es tracta d'un electròlit àcid que conté diverses impureses, entre les quals destaquen, Sb i Bi, que són considerats matèries primeres crítiques per la Unió Europea, a causa del risc de subministrament que presenten i a la seua importància en l'economia. L'objectiu d'esta Tesi és la recuperació del Sb i la reutilització de l'HCl. Per assolir aquests dos propòsits s'ha estudiat l'ús de l'electrodeposició com a operació de separació per al tractament de l'efluent. Este procés s'ha investigat mitjançant tècniques electroquímiques, en particular, voltametria cíclica i de rastreig lineal. En primer lloc, s'ha realitzat l'estudi amb dissolucions sintètiques que emulen l'efluent generat a les metal·lúrgies xilenes. La caracterització electroquímica de la dissolució de Sb en medi HCl ha evidenciat que la reducció del Sb(III) a Sb metàl·lic està limitada per la transferència de matèria i que una concentració elevada de HCl afavorix la recuperació del Sb. Els assajos d'electrodeposició han destacat la rellevància de les reaccions secundàries, la reacció d'evolució de l'hidrogen (HER) i la generació de clor, i la seua influència negativa sobre la deposició de Sb. La HER té lloc al càtode i comporta la generació de bambolles d'hidrogen a elevades densitats de corrent, la qual cosa reduïx la superfície útil de l'elèctrode de treball i fins i tot causa el despreniment del depòsit de Sb. Per la seua banda, la generació de clor gas a l'ànode provoca la redissolució dels depòsits de Sb despresos a causa de la HER. Després de la realització d'estos assajos s'ha conclòs que es pot augmentar la taxa de recuperació de Sb si es tenen majors concentracions de l'element en la dissolució o si es milloren les condicions hidrodinàmiques. S'ha analitzat també com influïx la presència de Bi en la dissolució sintètica durant l'electrodeposició del Sb. El potencial de reducció dels dos elements és similar, la qual cosa implica que la recuperació individual de Sb siga complexa. No obstant això, si es treballa sota condicions en què no se supere la densitat de corrent límit del sistema, s'aconseguix una elevada selectivitat cap al Sb. Si la concentració de Bi en la dissolució és superior a la de Sb, s'electrodepositen ambdós elements, però s'aconseguix un elevat valor d'eficiència de corrent pel fet que la influència de la HER sobre el Bi no és tan forta. A continuació, s'ha estudiat l'aplicació de les tècniques prèviament analitzades amb un efluent real, facilitat per una empresa espanyola. S'ha verificat que les conclusions obtingudes amb les dissolucions sintètiques són aplicables al efluent real. En particular, s'ha confirmat que, en augmentar la densitat de corrent aplicada, la deposició de Sb es veu minvada a causa de la rellevància de la resta de reaccions: la reducció dels altres elements i l'evolució del medi. Els depòsits obtinguts contenen alguns dels elements presents en el efluent real: Sb, Bi, As i Cu, sent majoritari el primer. Com a resultat, s'ha conclòs que és possible purificar l'HCl mitjançant l'electrodeposició dels elements continguts en l'electròlit. Finalment, s'ha plantejat la possibilitat de substituir l'HCl emprat com regenerant per un dissolvent eutèctic profund, a causa de l'alta solubilitat de metalls i la seua procedència de fonts renovables. En particular, la investigació s'ha dut a terme amb l'oxalina, la qual presenta una elevada capacitat de dissolució per al Sb i una àmplia finestra de potencial que beneficiaria l'aplicació de la tècnica d'electrodeposició per a la recuperació del Sb captat durant el procés de regeneració de les resines. / [EN] This Doctoral Thesis focuses on the recovery by electrodeposition of Sb present in an effluent from the copper metallurgy. The effluent on which this study is based is generated during the regeneration with concentrated hydrochloric acid of the ion exchange resins used in one of the sub-stages of copper electro-refining. It is an acid electrolyte containing several impurities, among them, Sb and Bi, which are considered critical raw materials by the European Union due to their supply risk and economic relevance. The aim of this Thesis is the recovery of Sb and reuse of HCl. To achieve both objectives, electrodeposition has been studied as a separation operation for the treatment of the effluent. This operation has been investigated through electrochemical techniques, primarily, cyclic and linear sweep voltammetry. First, the study has been conducted with synthetic solutions emulating the effluent generated in the Chilean metallurgy industries. The electrochemical characterization of the Sb solution in the HCl medium has shown that, mass-transfer limits the reduction of Sb(III) to metallic Sb and a high HCl concentration favors the recovery of Sb. From the electrodeposition tests the relevance and negative influence on Sb deposition of the secondary reactions, the hydrogen evolution reaction (HER) and the chlorine generation, has been proven. The HER occurs at the cathode and involves the generation of hydrogen bubbles at high current densities, which decrease the effective surface area of the working electrode and even cause the detachment of the Sb deposits. The chlorine generation at the anode leads to the redissolution of the Sb deposits detached by the HER. After conducting these experiments, it has been concluded that it is possible to increase the Sb recovery rate, if higher concentrations of this element are present in the solution or the hydrodynamic conditions of the electrodeposition process are improved. The influence of the presence of Bi in the synthetic solution on the Sb electrodeposition has also been investigated. The reduction potential of both elements is similar, implying that the individual recovery of Sb by electrodeposition is challenging. However, if the operating conditions do not imply exceeding the limiting current density of the system, a high electrodeposition selectivity towards Sb is achieved. If the concentration of Bi in the solution is higher than that of Sb, the simultaneous electrodeposition of both elements takes place, but, on the contrary, a high value of current efficiency is obtained because the influence of the HER on Bi reduction is not as significant as that on Sb deposition. The application of the previously analyzed techniques has been studied with a real effluent, that was provided by a Spanish company. It has been proven that the conclusions obtained with the synthetic solutions can be applied to a real effluent. It has been confirmed that, as the applied current density increases, the Sb deposition worsens due to the relevance of the other reactions that take place during the process: the reduction of the other elements and the evolution of the medium. The deposits obtained contain some elements present in the real effluent: Sb, Bi, As and Cu, the most significant being the first. From this study, it has been concluded that purifying the HCl by removing the elements contained in the electrolyte via electrodeposition is possible. Finally, the possibility of replacing the HCl used as a regenerant with a deep eutectic solvent has been considered based on their properties, among which are a high solubility of metals and their synthesis from renewable sources. In particular, the research has been carried out with oxaline, which presents a high dissolution capacity for Sb and a wide potential window that would benefit the application of the electrodeposition technique to recover Sb captured during the resins regeneration process. / Me gustaría agradecer la financiación a la Agencia Estatal de Investigación (AEI/10.13039/501100011033) (España) bajo el proyecto PCI2019-103535, gracias al cual he podido desarrollar la presente Tesis Doctoral, y a FEDER Una manera de hacer Europa / Hernández Pérez, L. (2024). Estudio electroquímico para la recuperación de antimonio de efluentes del electro-refinado de cobre por electrodeposición [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/203892

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Eutectic (63% tin-37% lead) or near-eutectic (40% tin-60% lead) tin-lead solder is widely used for creating electrical interconnections between the printed wiring board (PWB) and the components mounted on the board surface. For components mounted directly on the PWB mounting pads, that is, surface mounted components, the tin-lead solder also constitutes the mechanical interconnection. Eutectic solder has a melting point of 183°C (361°F). It is important to realize that its homologous temperature, defined as the temperature in degrees Kelvin over its melting point temperature (T(m)), also in degrees Kelvin, is defined as T/T(m). At room temperature (25°C = 298K), eutectic solder's homologous temperature is 0.65. It is widely acknowledged that materials having a homologous temperature ≥ 0.5 are readily subject to creep, and the solder joints of printed wiring assemblies are routinely exposed to temperatures above room temperature. Hence, solder joints tend to be subject to both thermal fatigue and creep. This can lead to premature failures during service conditions. The geometry, that is, the lead configuration, of the joints can also affect failure. Various geometries are better suited to withstand failure than others. The purpose of this paper is to explore solder joint failures of dual in-line (DIP) integrated circuit components, leadless ceramic chip carriers (LCCCs), and gull wing and J-lead surface mount components mounted on PWBs.

The compression behavior of a newly developed near eutectic Al-Si based cast alloy with three different microstructures has been investigated in the present work. Microstructures with modified and unmodified Si particles and matrix with different tempers are investigated. The main objective of this work is to understand the effect of heat treatment and modification on the fracture behavior of the alloy under compression. This alloy is subjected to compressive loading at different strain rates and temperatures during the operation of the engines. Hence, the effect of strain rates and temperatures is also considered. The compression tests are carried out at different strain rates from quasi-static to dynamic viz., 3*10-4 to 102/s and three different temperatures RT, 100°C and 200°C. Microstructure of the alloys studied predominantly consists of eutectic colonies of α-Al and Si with a few interspersed α-Al dendrites. Modified alloy has more globular Si particles than unmodified alloy. Heat treated alloys are found to have hardening precipitates S’ & Al7Cu4Ni and 3-7 atomic layer thick zones, which may be precursors to S’ phase. A variety of large intermetallics, viz., plate like particles Al4.5FeSi, Chinese script like particles Al19Fe4MnSi2 and bulky phase Al3NiCu are also observed in the alloys. Mechanical behavior of the alloys is found to be different for different microstructures. Modification improves strength and ductility. Heat treatment improves strength of the alloy at the expense of ductility. A transition in mechanical behavior is observed after a particular strain rate for all the alloys studied. This transition strain rate is dependent on heat treatment, Si particle size and temperature. This transition can be explained on the basis of dislocation-precipitate and dislocation-Si particle interactions. Work hardening behavior of the alloys depends on the matrix microstructure in the unmodified alloys, and both matrix and particles play a role in the modified alloy. A statistically robust quantitative micro structural analysis has been carried out after compressing the samples at various strain rates and temperatures. The unique contribution of this work is the understanding of combined effect of strain rate and temperature on Si particle fracture characteristics in the alloy with different microstructures. From the fracture characteristics of Si particles, it is concluded that both dislocation pile-up mechanism and fibre loading are responsible for particle fracture in the modified alloy, whereas the fibre loading mechanism alone is sufficient to explain the particle fracture characteristics in the unmodified alloy. Si particles in the modified condition are found to cleave along the lowest surface energy planes {112} & {110} and the particles with orientations {112} & {111} are more prone to fracture. In addition to Si particle fracture, elongated Fe rich intermetallic particles are also seen to show peculiar fracture behavior. The Al4.5FeSi intermetallics with (100) as the plane of the plate cleave along (100) planes. This is a novel finding in this work and could have immense implications on the role of Fe impurities in the fracture behavior of these alloys. Moreover, since these cleavage fractures are seen to be more than 200 microns in size (which implies that the real penny shaped crack would be even larger) their role cannot be assumed to be negligible, as was previously thought. The load sharing between the Al matrix and eutectic Si particles are simulated by microstructure based finite element modeling. The program OOF (Object-Oriented Finite element analysis) is used to generate the finite element meshes for real microstructures with different Si morphology. The experimentally obtained stress – strain properties of the alloy is given as an input to describe the plastic behavior of the Al matrix, in the finite element simulation. This analysis helps to understand the effect of particle size, shape, orientation & clustering and matrix temper on the stress transferred to the Si particles. Combination of Electron Back-Scattered Diffraction (EBSD) and frequency shift, polarized micro-Raman technique is applied to validate the stress states in Si particles with {111} orientations. The stress at fracture of Si particles is also estimated from Raman technique. Even though the alloys with different microstructures show different mechanical behavior, the sequence of fracture mechanisms is found to be same for all the alloys. The failure occurs in three stages: cracking of Si particles at low strains, micro-crack formation along the fractured particles, micro-crack coalescence and propagation leading to final failure. Thus, the proposed analysis links various deformation mechanisms ranging from nano precipitate-dislocation interactions to micro short-fiber theory of load sharing by eutectic silicon along with coupled effect of strain rate and temperature. In addition, negative strain rate sensitivity is also observed in the lower strain rate regimes (3*10-4, 10-3& 102/s) at RT and 100°C for all the three alloys, and serrated flow is also observed in the same strain rate and temperature regimes. Some of the features of serrated flow can be explained by the dynamic strain aging model and some other features by precipitate shearing.

This master’s thesis deals with usage of burn-up (spent) nuclear fuel in nuclear power plants of next generation – accelerator driven transmutation plants which is produced in current nuclear power plants. This system could significantly reduce the volume of dangerous long-lived radioisotopes and moreover they would be able to take advantage of its great energy potential due to fast neutron spectrum. In the introduction are listed basic knowledge and aspects of spent nuclear fuel along with its reprocessing and the possibility of further use while minimizing environmental impact. As another point detailed description of accelerator driven systems is described together with its basic components. In addition this search is followed by individual chronological enumeration of projects of global significance concerning their current development. Emphasis is placed on SAD and MYRRHA projects, which are used like base for calculations. This last, computational part, deals with the creation of the geometry of subcritical transmutation reactor driven by accelerator and subsequent evaluation which assembly is the most effective for transmutation and energy purposes along with changing of target, nuclear fuel and coolant/moderator.

ヘテロ構造組織を有する鉄・非鉄金属の組織形態に注目して,微視的構造やその挙動が巨視的現象(変形特性,成形性)として発現するメカニズムを解明することを目的とした.鉄系金属ではDual Phase型高張力鋼のスプリングバック現象のひずみ速度依存性,非鉄系金属では半凝固鋳造法と強ひずみ加工を組み合わせた亜共晶アルミニウム合金の衝撃後方押出し成形性に注目した.これらの検討によりいずれの試料においても,結晶粒界よりもスケールの大きいヘテロ構造に由来した変形機構が支配的であることが明らかになった. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University