Academic literature on the topic 'Melting of oxygen-free copper'
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Journal articles on the topic "Melting of oxygen-free copper"
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S. Kazem, Murtadha, and Isam M. Abdulbaqi. "DESIGN OF INDUCTION COIL FOR OXYGEN FREE COPPER PRODUCTION." Journal of Engineering and Sustainable Development 25, no. 4 (July 1, 2021): 51–57. http://dx.doi.org/10.31272/jeasd.25.4.5.
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This paper deals with the design of an induction coil (IC) intended to be used for an oxygen free copper production. This coil differs in design because it should be placed in a vacuum or in a chamber filled with noble gas, such as Argon. The designed coil must be suitable for melting the copper in this environment. The coil design means, using the simulation of the melting process to determine the best, coil geometry, type of crucible, the required current, frequency, the consumed power, and time required for this process. These results will be used to determine the parameters of the induction furnace AC power source suitable for feeding such a melting process efficiently. The Finite Element Analysis (FEA) intended to simulate the heating process to determine the best coil dimensions, and choosing the crucible. It is found that the best crucible used for the melting of copper is the carbon crucible.
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Guo, Ming En, Yun Xu Shi, and Yu Chen Guo. "Research on Oxygen Content and Crack Control of Oxygen-Free Copper Billet in Horizontal Continuous Casting Process." Advanced Materials Research 569 (September 2012): 264–67. http://dx.doi.org/10.4028/www.scientific.net/amr.569.264.
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In this paper, research on reducing oxygen content and crack in oxygen-free copper strip during horizontal continuous casting process has been taken. First, reform the original copper alloy smelting-holding-casting three stages process. Through developing melting and holding integrative furnace, combine melting process and holding process for one, reforming smelting holding-casting two stages process. Second, pick up and realize on-off valve technics on controlling flow or stop of undercurrents copper liquid. Third, analyze the cracks in oxygen-free copper billet with flakinessratio 6500/20mm. And finally determine reasonable cooling process parameters through experiments. The results shows when oxygen content ≤0.0004% and density rise to 8.94-8.95 g/cm3, the crack has been completely eliminated.
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Lei, H. "Melting of free copper clusters." Journal of Physics: Condensed Matter 13, no. 13 (March 15, 2001): 3023–30. http://dx.doi.org/10.1088/0953-8984/13/13/315.
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Lee, Jung Il, Joo Ho Lee, Seung Hwan Park, Han Shin Choi, Hoon Cho, Hyung Ho Jo, Skae K. Kim, Hyuk Chon Kwon, and Jung Eui Hong. "Design of Manufacturing Process of Oxygen-Free High Conductivity Copper Using Mahalanobis-Distance Outlier Detection Method." Materials Science Forum 544-545 (May 2007): 965–68. http://dx.doi.org/10.4028/www.scientific.net/msf.544-545.965.
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The proper control of total impurities and oxygen contents of oxygen-free high conductivity (OFHC) copper prepared by vacuum high-frequency melting technique was studied using Mahalanobis-Distance (MD) outlier detection method as functions of raw material purities, vacuum pressure, melting temperature and holding time. The properties of vacuum-melted OFHC copper was examined by thermo-gravimetric analysis, differential scanning calorimetry, hardness test, macro and optical microstructure analyses and ultimate tensile test. In multivariate systems, the existence of outlier makes it difficult to analyze the system and oultier detection belongs to the most important tasks in experimental data analysis. Mahalanobis Distance is most commonly used as a diagnosis of existance of outlier in multivariate system. The relationship between experiment conditions and total impurities and oxygen contents can be defined with the regression analysis results. At this research, our desirable manufacturing conditions is to obtain the total impurities under 40 ppm and oxygen contents under 5 ppm. After this statistical approach, the suggested minimum maufacturing conditions are the purity of raw material was 4N, vacuum pressure was 10-1 torr, melting temperature was 1150°C and melt holding time was 20 minutes.
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Stefanova, V., K. Vutova, and V. Vassileva. "Thermodynamic analysis of the processes during electron beam melting and refining of copper." Journal of Physics: Conference Series 2240, no. 1 (March 1, 2022): 012034. http://dx.doi.org/10.1088/1742-6596/2240/1/012034.
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Abstract In the paper, results are presented and discussed obtained by thermodynamic analysis of the refining processes of copper aimed at removing metal impurities and oxygen via electron beam melting (EBM) in vacuum. Thermodynamic evaluations of the possible chemical interactions between the base metal (Cu) and the metal impurities present in Cu that can proceed during the refining of copper are made based on the calculated values of the Gibbs free energy and equilibrium constants taking into account the physical state of copper and of the metal impurities during EBM.
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Tsao, Lung-Chuan, Cheng-Kai Li, Yu-Kai Sun, Shih-Ying Chang, and Tung-Han Chuang. "Fluxless Direct Soldering of Transparent Conductive Oxides (TCOs) to Copper." Advances in Materials Science and Engineering 2021 (November 15, 2021): 1–7. http://dx.doi.org/10.1155/2021/8069719.
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Due to the combined advantages of low cost, good soldering properties, and appropriate melting temperature range, novel Sn8Zn3Bi1Mg active solder was developed for direct soldering of transparent conductive oxide (TCO) ceramic targets with oxygen-free copper at 200°C in air. The TCO specimens have aluminum-doped zinc oxide (AZO) and zinc oxide (ZnO) ceramics. The direct soldering process was performed without the need for flux or pre-metallization of the two transparent conductive oxides. The microstructure, phase constitution, melting characteristics, and soldering properties of the Sn8Zn3Bi1Mg active solder were investigated. The liquidus temperature of the Sn8Zn3Bi1Mg active solder was 198.6°C, which was very close to the binary Sn-Zn eutectic temperature of 198.5°C. The effect of temperature on the bonding strength of the solder joints was evaluated. The shear strengths of AZO/Cu and ZnO/Cu joints soldered with Sn8Zn3Bi1Mg active solder were 10.3 and 7.5 MPa at room temperature, respectively. Increasing the temperature from room temperature to 180°C reduced the bonding shear strengths of AZO/Cu and ZnO/Cu joints to 3.3 and 3.7 MPa, respectively.
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Li, Jianxing, Daniel Lau, Pingliang Tu, Andrew Delano, and Brian Knight. "High Melting Temperature Lead Free Solder for Die Attach Application." International Symposium on Microelectronics 2011, no. 1 (January 1, 2011): 000322–26. http://dx.doi.org/10.4071/isom-2011-tp4-paper1.
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Two lead free solders were developed for die attach application. The bismuth based solder has a melt temperature of 271C and thermal conductivity of 18W/mK. The zinc based solder has a melt temperature of 337C and thermal conductivity of 85W/mK. Both solders have acceptable wetting on bare copper and nickel plated copper substrate, could be processed using modified high lead solder process condition and survived 260C board level reflow simulation. This paper discusses the solder material properties, and presents the die attach process and reliability test results in a manufacturing environment.
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De Lucia, M. "Oxygen Enrichment in Combustion Processes: Comparative Experimental Results From Several Application Fields." Journal of Energy Resources Technology 113, no. 2 (June 1, 1991): 122–26. http://dx.doi.org/10.1115/1.2905785.
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The effects of using oxygen to partially or wholly replace fuel air in small-size melting furnaces were studied over a range of application fields. Following definition of the useful parameters, testing was conducted on furnaces for melting glass, ferrous metals (pigiron), nonferrous metals (copper alloys), and ceramic materials. In all cases, oxygen-enrichment was found to provide significant energy savings, as well as notable advantages in terms of both plant output and energy consumption.
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Ledford, Christopher, Christopher Rock, Paul Carriere, Pedro Frigola, Diana Gamzina, and Timothy Horn. "Characteristics and Processing of Hydrogen-Treated Copper Powders for EB-PBF Additive Manufacturing." Applied Sciences 9, no. 19 (September 24, 2019): 3993. http://dx.doi.org/10.3390/app9193993.
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The fabrication of high purity copper using additive manufacturing has proven difficult because of oxidation of the powder feedstock. Here, we present work on the hydrogen heat treatment of copper powders for electron beam powder bed fusion (EB-PBF), in order to enable the fabrication of high purity copper components for applications such as accelerator components and vacuum electronic devices. Copper powder with varying initial oxygen contents were hydrogen heat-treated and characterized for their chemistry, morphology, and microstructure. Higher initial oxygen content powders were found to not only reduce surface oxides, but also reduce oxides along the grain boundaries and form trapped H2O vapor inside the particles. The trapped H2O vapor was verified by thermogravimetric analysis (TGA) and residual gas analysis (RGA) while melting. The mechanism of the H2O vapor escaping the particles was determined by in-situ SEM heated stage experiments, where the particles were observed to crack along the grain boundaries. To determine the effect of the EB-PBF processing on the H2O vapor, the thermal simulation and the validation of single melt track width wafers were conducted along with melting single layer discs for chemistry analysis. A high speed video of the EB-PBF melting was performed in order to determine the effect of the trapped H2O vapor on the melt pool. Finally, solid samples were fabricated from hydrogen-treated copper powder, where the final oxygen content measured ~50 wt. ppm, with a minimal residue hydrogen content, indicating the complete removal of trapped H2O vapor from the solid parts.
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Song, Shu Xiang, Zhang Jian Zhou, Juan Du, and Chang Chun Ge. "Study on Interfacial Characterization and Mechanical Properties of Plasma-Sprayed Tungsten Coatings." Materials Science Forum 546-549 (May 2007): 1809–12. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.1809.
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Tungsten has the highest melting point among all metal, which makes it withstand thermal shock and erosion in high temperature environments. In this study, Tungsten coatings were sprayed onto the oxygen-free copper substrates by plasma spraying using inert gases protection. XRD, SEM and EDS were used to identify the phases, morphologies and compositions of the coatings. Vickers micro-hardness and bonding strength of the tungsten coatings were also measured. The results revealed that the hardness distribution of the tungsten coatings was different along the thickness direction. The tungsten coating without any interlayer showed higher bonding strength than that of the other two coatings with NiCrAl and W/Cu interlayers, respectively.
Dissertations / Theses on the topic "Melting of oxygen-free copper"
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Білянін, Роман Володимирович. "Тепловий контроль технічного стану індукційних установок для виробництва мідної катанки." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41338.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.11.13 – прилади і методи контролю та визначення складу речовин. – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2019 р.
У дисертації вирішено важливе наукове завдання розвитку методів теплового контролю технічного стану індукційних установок виробництва високоякісної мідної катанки на основі використання математичного моделювання електротеплових процесів, аналізу розподілу температури в багатошаровій термоізоляції установок з урахуванням її деградації та розподілу температури на їх поверхні, що має суттєве значення для розвитку кабельної промисловості. Розроблено новий метод неруйнівного контролю технічного стану індукційних установок для виготовлення мідної катанки енергетичного призначення, в якому крім вимірювання реактивного та активного опорів індуктора та різниці температури води у системі охолодження додатково визначається ступінь деградації багато-шарової термоізоляції шляхом порівняння розрахункового розподілу поточної температури в об'ємі розплаву та ізоляції на тривимірній математичній моделі установки з практичним вимірюванням температури локальних областей (у роботі їх було 72) поверхні корпусу печі. Це дає можливість точніше прогнозувати ресурс печі та завчасно виявляти режими її роботи близькі до аварійних. Розроблено нове технічне рішення з удосконалення багатошарової термоізоляції індукційних установок з метою зменшення їхніх енерговитрат і збільшення ресурсу. Воно полягає у застосуванні замість третього термоізоляційного шару з легковагої цегли трьох шарів: монолітного вогнетривкого бетону, легковагої цегли та вогнетривкого паперу, зі збереженням загальної товщини ізоляції. Впровадження результатів дисертації в індукційній установці UPCAST US20X-10 для виготовлення мідної катанки в ПАТ "ЗАВОД ПІВДЕНКАБЕЛЬ" дало позитивні результати у зниженні на 20°C температури на корпусі печі, скороченні на 5-15% питомої витрати електроенергії на 1 тонну катанки та поліпшенні її якості шляхом зменшення відсотку сторонніх домішок і забезпечення вмісту в ній міді 99,99%.The thesis for a Candidate of Engineering Sciences degree by specialty 05.11.13 – devices and methods of control and determination of composition of substances. – National technical university "Kharkov polytechnic institute", Kharkiv, 2019. The thesis solves the important scientific task to improve methods of control of the technical condition of induction installations for the production of high-quality copper rod using the mathematical modeling of electrothermal processes in copper melt and multi-layer thermal insulation, with taking into account its degradation and temperature distribution on the installation surface, which is essential for the development of cable industry. A new method of non-destructive control of the technical condition of induction installations for the production of copper rod for power cables of energy value is developed, in which in addition to measuring the reactive and active resistances of the inductor and the reduction of the water temperature in the cooling system, the degree of degradation of multilayer thermal insulation is additionally determined by comparing the calculated distribution of the current temperature in the volume of melt and insulation on a three-dimensional mathematical model of the installation with practical measurement of temperature in local areas (in the work they were 72) of the surface of the furnace casing. This makes it possible to more accurately predict the furnace's profile and to detect the modes of its operation in a timely manner close to the emergency. A new technical solution for improving the multilayer thermoinsulation of induction installations has been developed in order to reduce their energy consumption and increase the resource. It consists in applying instead of the third thermal insulation layer of light-weight brick of three layers: monolithic refractory concrete, lightweight brick and refractory paper, with the preservation of the overall thickness of the insulation. The implementa-tion of the developed lining structure improvement at PJSC " YUZHCABLE WORKS" in the UPCAST US20X-10 induction installation for copper rod in the cable industry in Ukraine has yielded positive results in a 20°C decrease in the temperature of the furnace casing, a reduction of 5-15% of the specific cost Electricity for 1 ton of production and improvement of quality of copper rod, by reducing the percentage of foreign impurities and ensuring copper content in it 99,99%.
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Білянін, Роман Володимирович. "Тепловий контроль технічного стану індукційних установок для виробництва мідної катанки." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41340.
Full textAbstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.11.13 – прилади і методи контролю та визначення складу речовин. – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2019 р.
У дисертації вирішено важливе наукове завдання розвитку методів теплового контролю технічного стану індукційних установок виробництва високоякісної мідної катанки на основі використання математичного моделювання електротеплових процесів, аналізу розподілу температури в багатошаровій термоізоляції установок з урахуванням її деградації та розподілу температури на їх поверхні, що має суттєве значення для розвитку кабельної промисловості. Розроблено новий метод неруйнівного контролю технічного стану індукційних установок для виготовлення мідної катанки енергетичного призначення, в якому крім вимірювання реактивного та активного опорів індуктора та різниці температури води у системі охолодження додатково визначається ступінь деградації багато-шарової термоізоляції шляхом порівняння розрахункового розподілу поточної температури в об'ємі розплаву та ізоляції на тривимірній математичній моделі установки з практичним вимірюванням температури локальних областей (у роботі їх було 72) поверхні корпусу печі. Це дає можливість точніше прогнозувати ресурс печі та завчасно виявляти режими її роботи близькі до аварійних. Розроблено нове технічне рішення з удосконалення багатошарової термоізоляції індукційних установок з метою зменшення їхніх енерговитрат і збільшення ресурсу. Воно полягає у застосуванні замість третього термоізоляційного шару з легковагої цегли трьох шарів: монолітного вогнетривкого бетону, легковагої цегли та вогнетривкого паперу, зі збереженням загальної товщини ізоляції. Впровадження результатів дисертації в індукційній установці UPCAST US20X-10 для виготовлення мідної катанки в ПАТ "ЗАВОД ПІВДЕНКАБЕЛЬ" дало позитивні результати у зниженні на 20°C температури на корпусі печі, скороченні на 5-15% питомої витрати електроенергії на 1 тонну катанки та поліпшенні її якості шляхом зменшення відсотку сторонніх домішок і забезпечення вмісту в ній міді 99,99%.The thesis for a Candidate of Engineering Sciences degree by specialty 05.11.13 – devices and methods of control and determination of composition of substances. – National technical university "Kharkov polytechnic institute", Kharkiv, 2019. The thesis solves the important scientific task to improve methods of control of the technical condition of induction installations for the production of high-quality copper rod using the mathematical modeling of electrothermal processes in copper melt and multi-layer thermal insulation, with taking into account its degradation and temperature distribution on the installation surface, which is essential for the development of cable industry. A new method of non-destructive control of the technical condition of induction installations for the production of copper rod for power cables of energy value is developed, in which in addition to measuring the reactive and active resistances of the inductor and the reduction of the water temperature in the cooling system, the degree of degradation of multilayer thermal insulation is additionally determined by comparing the calculated distribution of the current temperature in the volume of melt and insulation on a three-dimensional mathematical model of the installation with practical measurement of temperature in local areas (in the work they were 72) of the surface of the furnace casing. This makes it possible to more accurately predict the furnace's profile and to detect the modes of its operation in a timely manner close to the emergency. A new technical solution for improving the multilayer thermoinsulation of induction installations has been developed in order to reduce their energy consumption and increase the resource. It consists in applying instead of the third thermal insulation layer of light-weight brick of three layers: monolithic refractory concrete, lightweight brick and refractory paper, with the preservation of the overall thickness of the insulation. The implementa-tion of the developed lining structure improvement at PJSC " YUZHCABLE WORKS" in the UPCAST US20X-10 induction installation for copper rod in the cable industry in Ukraine has yielded positive results in a 20°C decrease in the temperature of the furnace casing, a reduction of 5-15% of the specific cost Electricity for 1 ton of production and improvement of quality of copper rod, by reducing the percentage of foreign impurities and ensuring copper content in it 99,99%.
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Alawadhi, Meshal Y. "Microstructural evolution and mechanical properties of oxygen-free copper processed by severe plastic deformation." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/415750/.
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This thesis presents a study on the microstructural evolution and mechanical properties of oxygen-free copper processed by equal-channel angular pressing (ECAP) and high-pressure torsion (HPT) at room temperature. Experiments were systematically conducted to examine microstructural stability and deformation mechanisms, and their influence on the mechanical properties. A significant grain refinement was attained after deforming the material by 24 passes of ECAP and 10 turns of HPT. The microstructure in the steady-state condition consisted of equiaxed ultrafine grains (UFGs) with high-angles of misorientation. Hardness values increase with increasing number of ECAP passes and HPT turns, and the microhardness distribution was relatively homogenous. ECAP and HPT samples were pulled to failure at room temperature using strain rates of 1.0×10-4 s-1, 1.0×10-3 s-1 and 1.0×10-2 s-1. The direct influence of recovery behaviour on the tensile properties was investigated. A simultaneous increase in strength and ductility were observed with increasing number of ECAP passes as well as HPT turns. This is due to occurrence of dynamic recovery at an equivalent strain of ~12 that decreases the total dislocation density and restores the work hardening ability of oxygen-free copper. Both grain boundary and dislocation strengthening mechanisms contribute to the strength of oxygen-free copper. Higher ductility but lower strength was observed when using lower strain rates. UFG copper samples produced by HPT were stored at room temperature for 12 months to investigate microstructural stability and self-annealing phenomena. The results show that the samples processed by a low number of turns exhibit lower thermal stability after storage of 12 months in comparison to the samples processed by a high number of turns. A significant decrease in the hardness was recorded near the edges of the discs processed by 1/4, 1/2 and 1 turn due to recrystallization and grain growth whereas a minor drop in hardness values were observed in the samples processed by 3, 5 and 10 turns, and this drop was related to the recovery mechanism. Tensile tests were repeated after 12 months and the results showed that the ductility was enhanced in compensation for strength. To investigate the deformation mechanism and thermal stability under high strain rates, copper samples were subjected to 1, 4 and 8 passes of ECAP and further deformed by dynamic testing. A significant grain refinement was produced in the ECAP specimens after dynamic testing which is comparable to the grain refinement produced by severe plastic deformation (SPD) techniques such as ECAP and HPT. The grain refinement mechanism was mainly by dislocation slip in the specimen processed by 1 pass whereas it was through dynamic recrystallization for the specimen processed by 8 passes. This is due to the difference in the dislocation densities and stored energy between the ECAP specimens. A 1 pass specimen has better stability than 4 and 8-pass specimens during dynamic testing. It was also shown that increasing the testing temperature and/or the strain rate can highly influence the deformation mechanism.
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Liggett, Jennifer. "Microelectrode Investigation of Iron and Copper Surfaces Exposed to Free Chlorine Under Relevant Drinking Water Chemistries." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439562284.
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Ching-HuiHuang and 黃景暉. "The Characteristic Study of Laser Welding on Oxygen-free Copper Sheet." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/50623026818190786862.
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碩士國立成功大學
機械工程學系碩博士班
101
This study investigated the laser weldability and welding process window of three different copper sheets: the oxygen-free copper (OFC), OFC coated with nickel or OFC coated with tin, on the SPCC (thickness 0.2mm) where Lap-Joint welding by laser were performed. The mechanical properties test and microstructure analysis of the welding joint were used to examine the degree of conductivity, strength and microstructure characteristics in different materials and parameters. The welding ability of corrosion resistance at general environmental was analyzed by electrochemical test. Finally, the optimum welding process window as laser welding of copper sheet would be obtained. As the results of the experiment, the base material – OFC coated with tin had the maximum laser absorptivity. At the beginning of welding, it would form the copper-tin alloy with low melting point at the weld fusion zone, so the heat could be effectively passed down to SPCC. Thus, OFC coated with tin would achieve satisfactory laser weldability among three different copper sheets. The molten zone was raised up with the increasing defocus distance to expand the process window and spot area gradually. There were optimum effect of welding when the defocuses distance were at 9mm and 10mm. As the analysis of the experiment, there was the maximum welding diameter 955um under defocused 9mm, pulse width 10ms, peak power 10kW, shielding gas (Ar) flow rate 10L/min, which would have the maximum tensile force of 74.3N and minimum resistance of 0.217 mΩ. But there was poor corrosion resistance due to the content of iron ions with 38% at diffusion layer which would cause the selective corrosion easily.
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Chang, He-Chieh, and 張賀傑. "Mechanical Properties of Oxygen-Free Copper Wire the Fine Wire Drawing." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/99916320895419538143.
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碩士國立宜蘭大學
機械與機電工程學系
101
The study for mechanical properties and plastic behavior when OFC(Oxygen-Free Copper) wire be go through different size of diamond dies,than record it what effect on skin pass. The original size of OFC isφ1.0mm, passing through 13 pass to 0.1mm.Than it,which after annealed at 350℃,be passed through 10 pass to φ0.03mm.In accordance with CNS2112,the original gauge length of tensile specimen is 9A. In accordance with CNS2111,the Electrical Material Testing Machine be set up for adding load should be linearly.In accordance with CNS9504, by Optical Microscopy metallographic analysis that longitudinal section of wire be detected. The results saying,first,the one dies passes drawing to discover the relationship with drawing loading,reduce rate and stress in wire drawing. Second,from tensile test,we can derived the formula about coefficient of friction and die surface pressure when passing the dies. In the study, The data were obtained from experiments will reference for fine wire drawing process.
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Lin, Zong-Xian, and 林宗憲. "The Study of the Optimum Dies Used for Fine Wire Drawing for the Oxygen-Free Copper Wire." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/q3a82z.
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碩士國立宜蘭大學
機械與機電工程學系碩士班
103
The production of fine metal wire is usually used drawing process. The drawing process mean metal wire be drawing for multi-pass dies , to achieve the desired diameter of the wire. This paper use the finite element analysis with commercial package of LS-DYNA to investigate oxygen –free copper wire.To simulate drawing process of matel wire.The drawing load of simulate contrast with experiment.The max reduction of area were attained,and recorded the drawing load.In the study‚which find the max reduction of area is 15% between ψ30μm toψ17μm‚and 14%betweenψ16μm toψ11μm.
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Tsai, Ming-Hua, and 蔡明樺. "Study on the Semi-solid Temperature of Ternary Hypoeutectic Filler Metal for Vacuum Brazing of Oxygen-free Copper." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/45178657584977454533.
Full textAbstract:
碩士大葉大學
機械與自動化工程學系
101
Oxygen-free copper is one of the major structural materials of electric motors. With the bonding temperature of copper rotor being too high, the recrystallization of electric steels will lead to increased iron loss and reduced energy conversion efficiency. Therefore, in this study the low temperature semi-solid vacuum brazing technology has been adopted to accomplish a precise bonding between oxygen-free copper while maintaining high energy conversion efficiency. In this experiment the Cu-15Ag-5P is adopted as the filter metal, with the test conditions of liquid-solid phase coexistence temperature at 673 °C ~ 793 °C, liquid phase temperature at 823 °C, and a vacuum of <10-5 Torr. The experimental results have indicated that, based on DSC thermal analysis, the low melting point ternary hypoeutectic structure of filler metal started to melt at 643 °C. At 673 °C, the wetting angle of filler metal with respect to oxygen-free copper (C101) is 39.22° with a spreading area of 7.6㎜2. At 823 °C of liquid phase, the wetting angle has been reduced by 90 % (3.78°) as compared to that of 673°C, while the spreading area has grown by 192 % (22.16㎜2). However, the wetting angles are all less than 90°, indicating good wettability of filler metal with respect to C101. Based on the SEM/EDX analysis, the weld base (matrix) is black copper phosphorus solid solution with 3:1 composition ratio between Cu and P atoms such that it is determined to be in Cu3P phase, and weld hardness will be higher than the base material on both sides. The weld hardness of semi-solid temperature vacuum brazing is higher than the liquid phase bonding. At 673 °C the maximum hardness has reached 157.05 Hv, which is 192 % of the base material. At 823 °C the minimum hardness is at 94.81 Hv, which is only 80 % of the base material. Based on assessment of resistance measurement, under the impact of diffusion of filler metal, the resistance of C101 has been increased by 0.05~0.07 mΩ, indicating minor influence of brazing temperature on conducting effect between C101. As for the electrical steels for simulating vacuum brazing process, the resistance at semi-solid phase 733 °C is only 0.29 mΩ (0.03 %) less than the original state, while the maximum difference in resistance (1.79 mΩ) takes place at liquid phase 823 °C (20%). This shows that bonding temperature will indeed affect the electrical property of electrical steels. In the end, 1㎜ thick specimen has been used for tensile and shear stress test, and the breaking positions are all on base material for bonding length of 2T and 4T. This indicates that the bonding shear strength of weldment of low temperature vacuum brazing process in liquid-solid coexisting phase of filler metal Cu-Ag-P can be in line with the requirements.
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Huang, Chung-Hao, and 黃仲豪. "Research on the Development of a Meso-scale 3-axis Milling Machine and the Optimal Micro-milling Parameters for the Oxygen Free Copper." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/j753w4.
Full textAbstract:
碩士國立臺灣科技大學
機械工程系
100
There are two main parts in this study. First, the development of a meso-scale 3-axis milling machine has been introduced. Second, the optimal micro-milling parameters have been determined for cutting the oxygen free copper using a high speed spindle. The developed micro 3-axis milling machine system is constructed with a XY coplanar stage and a Z-axis high-speed spindle clamping mechanism mounted on a pagoda structure. The XY coplanar stage and Z-axis structural were guided by a linear guideways. The developed machine tool was driven by the LNC-M600 CNC controller and Elmo digital servo driver for the precision motion control of the linear motors. Based on the test results, the closed loop 3-axis milling machine system was able to provide precision positioning with the travel of 50 mm along XY-axis and the travel of 30 mm along Z-axis. By utilizing the LNC-M600 CNC controller and Elmo digital servo driver closed-loop of PID control system, the positioning capability of X-axis was about 30 nm, Y-axis was about 40 nm, and Z-axis was about 30 nm. Based on the linear displacement measurement results, the system error along X-axis was 0.00267~-0.00183 mm, Y-axis was 0.00093~-0.00591mm, and Z-axis was -0.00125~-0.00402 mm. The Taguchi’s experimental method was applied to determine the optimal micro-milling parameters for the oxygen free copper by using a micro-mill with a diameter of 0.2 mm. Based on the results of Taguchi’s L9 matrix experimen and the analysis of variation (ANOVA), the optimal micro-milling parameters for milling the oxygen free copper were the combination of the spindle speed of 50,000 rpm, the depth of cut of 0.005 mm ,the stepover of 0.02 mm, and the feed of 75 mm/min.
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TSAI, CHIN MING, and 蔡誌銘. "Development of a A-C Rotary Table for a Meso-scale 5-axis Machine Tool and the Optimal Micro-milling Parameters for the Oxygen Free Copper." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/02405461169330510223.
Full textAbstract:
碩士國立臺灣科技大學
機械工程系
101
This study presents the development of A-C rotary table for a Meso-scale 5-axis milling machine and the determination of the optimal micro-milling parameters. The whole five-axis Meso-scale milling machine feeding mechanism is constructed from three structures which are X Y coplanar stage, a Z-axis mechanism and A-C rotating table. With regard to the determination of the optimal micro-milling parameters, the quality characteristicis the minimum surface roughness of the milled surface.The surface is finished by a micro mill with diameter of 0.1 mm. The Taguchi’s experimental plan method has been applied to get the optimal parameters. After the optimal parameters have been determined, they were applied to manufacture the micro channels and helix micro groove on a copper cylinder. The burr problem of the fabricated micro channels is removed by the abrasive multi-jet polishing process. The optimal micro-milling parameters for milling the oxygen free copper were the combination of the feed of 20 mm/min, the depth of cut of 0.003 mm,the stepover of 0.009 mm, and the spindle speed of 100,000 rpm. The cutting force measured by a micro-dynamometer were 0 N, 0.008 N, and 0.135 N, respectively, with respect to X-, Y-, and Z-axes.
Book chapters on the topic "Melting of oxygen-free copper"
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Spittel, Marlene, and Thilo Spittel. "Flow stress, mechanical and physical properties of oxygen-free electronic copper (Cu-OFE)." In Part 3: Non-ferrous Alloys - Heavy Metals, 122–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-642-14174-4_6.
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Fickett, F. R., and T. E. Capobianco. "Relationships between Mechanical and Magnetoelectric Properties of Oxygen-Free Copper at 4 K." In Advances in Cryogenic Engineering Materials, 421–27. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4613-9871-4_51.
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Lee, Jung Il, Joo Ho Lee, Seung Hwan Park, Han Shin Choi, Hoon Cho, Hyung Ho Jo, Skae K. Kim, Hyuk Chon Kwon, and Jung Eui Hong. "Design of Manufacturing Process of Oxygen-Free High Conductivity Copper Using Mahalanobis-Distance Outlier Detection Method." In Materials Science Forum, 965–68. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-431-6.965.
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ENDO, Hiroki, Harumitsu SENDA, Shoichi YASUBA, and Etsuo MARUI. "Ultra-Precision Machining of Oxygen-Free Copper and Aluminium." In International Progress in Precision Engineering, 813–24. Elsevier, 1993. http://dx.doi.org/10.1016/b978-0-7506-9484-1.50092-0.
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"Hydrogen-Induced Cracking of Oxygen-Free Phosphorus-Doped Copper." In International Hydrogen Conference (IHC 2012), 451–60. ASME Press, 2014. http://dx.doi.org/10.1115/1.860298_ch48.
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Wu, Chun-Mu, and Chang-Rong Huang. "Numerical simulation on Friction Stir Welding of aluminum alloy and oxygen-free copper." In Applied System Innovation, 293–97. CRC Press, 2016. http://dx.doi.org/10.1201/b21811-62.
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Tacke, Thomas, and Peter Panster. "Selective and Complete Hydrogenation of Vegetable Oils and Free Fatty Acids in Supercritical Fluids." In Green Chemistry Using Liquid and Supercritical Carbon Dioxide. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780195154832.003.0020.
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As described in other chapters of this book and elsewhere (Jessop, 1999), a wide range of catalytic reactions can be carried out in supercritical fluids, such as Fischer–Tropsch synthesis, isomerization, hydroformylation, CO2 hydrogenation, synthesis of fine chemicals, hydrogenation of fats and oils, biocatalysis, and polymerization. In this chapter, we describe experiments aimed at addressing the potential of using supercritical carbon dioxide (and carbon dioxide/propane mixtures) for applications in the hydrogenation of vegetable oils and free fatty acids. Supercritical fluids, particularly carbon dioxide, offer a number of potential advantages for chemical processing including (1) continuously tunable density, (2) high solubilities for many solids and liquids, (3) complete miscibility with gases (e.g., hydrogen, oxygen), (4) excellent heat and mass transfer, and (5) the ease of separation of product and solvent. The low viscosity and excellent thermal and mass transport properties of supercritical fluids are particularly attractive for continuous catalytic reactions (Harrod and Moller, 1996; Hutchenson and Foster, 1995; Kiran and Levelt Sengers, 1994; Perrut and Brunner, 1994; Tacke et al., 1998). There are a number of reports on hydrogenation reactions in supercritical fluids using homogenous and heterogeneous catalysts (Baiker, 1999; Harrod and Moller, 1996; Hitzler and Poliakoff, 1997; Hitzler et al., 1998; Jessop et al., 1999; Meehan et al., 2000; van den Hark et al., 1999). We have investigated the selective hydrogenation of vegetable oils and the complete hydrogenation of free fatty acids for oleochemical applications, since there are some disadvantages associated with the current industrial process and the currently used supported nickel catalyst. The hydrogenation of fats and oils is a very old technology (Veldsink et al., 1997). It was invented in 1901, by Normann, in order to increase the melting point and the oxidation stability of fats and oils through selective hydrogenation. Since the melting point increases during the hydrogenation, the reaction is also referred to as hardening. The melting behavior of the hydrogenated product is determined by the reaction conditions (temperature, hydrogen pressure, agitation, hydrogen uptake). Vegetable oils (edible oils) are hydrogenated selectively for application in the food industry; whereas free fatty acids are completely hydrogenated for oleochemical applications (e.g., detergents).
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Monaghan, D., and R. D. Arnell. "Deposition of thick films of oxygen-free high conductivity copper by unbalanced d.c. magnetron sputtering: self-biased and biased conditions." In Metallurgical Coatings and Thin Films 1991, 298–303. Elsevier, 1991. http://dx.doi.org/10.1016/b978-0-444-89455-7.50059-9.
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A. Ikner, Luisa, and Charles P. Gerba. "Antiviral Coatings as Continuously Active Disinfectants." In Disinfection of Viruses [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101752.
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Antimicrobial surfaces and coatings have been available for many decades and have largely been designed to kill or prevent the growth of bacteria and fungi. Antiviral coatings have become of particular interest more recently during the COVID-19 pandemic as they are designed to act as continuously active disinfectants. The most studied antiviral coatings have been metal-based or are comprised of silane quaternary ammonium formulations. Copper and silver interact directly with proteins and nucleic acids, and influence the production of reactive free radicals. Titanium dioxide acts as a photocatalyst in the presence of water and oxygen to produce free radicals in the presence of UV light or visible light when alloyed with copper or silver. Silane quaternary ammonium formulations can be applied to surfaces using sprays or wipes, and are particularly effective against enveloped viruses. Continuously active disinfectants offer an extra barrier against fomite-mediated transmission of respiratory and enteric viruses to reduce exposure between routine disinfection and cleaning events. To take advantage of this technology, testing methods need to be standardized and the benefits quantified in terms of reduction of virus transmission.
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Das, Souvik, and Asish R. Basu. "Origin of the Indus ophiolite linked to the mantle transition zone (410–660 km)." In Plate Tectonics, Ophiolites, and Societal Significance of Geology: A Celebration of the Career of Eldridge Moores. Geological Society of America, 2021. http://dx.doi.org/10.1130/2021.2552(02).
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ABSTRACT The southeast Ladakh (India) area displays one of the best-preserved ophiolite sections in this planet, in places up to 10 km thick, along the southern bank of the Indus River. Recently, in situ, ultrahigh-pressure (UHP) mineralogical evidence from the mantle transition zone (MTZ; ∼410–660 km) with diamond and reduced fluids were discovered from two peridotite bodies in the basal mantle part of this Indus ophiolite. Ultrahigh-pressure phases were also found by early workers from podiform chromitites of another coeval Neo-Tethyan ophiolite in southern Tibet. However, the MTZ phases in the Indus ophiolite are found in silicate peridotites, but not in metallic chromitites, and the peridotitic UHP phases show systematic and contiguous phase transitions from the MTZ to shallower depth, unlike the discrete UHP inclusions, all in Tibetan chromitites. We observe consistent change in oxygen fugacity (fO2) and fluid composition from (C-H + H2) to (CO2 + H2O) in the upwelling peridotitic mantle, causing melting to produce mid-ocean-ridge basalt (MORB). At shallow depths (<100 km) the free water stabilizes into hydrous phases, such as pargasitic amphibole, capable of storing water and preventing melting. Our discoveries provide unique insights into deep sub-oceanic-mantle processes, and link deep-mantle upwelling and MORB genesis. Moreover, the tectonic setting of Neo-Tethyan ophiolites has been a difficult problem since the birth of the plate-tectonics concept. This problem for the origin of ophiolites in mid-ocean-ridge versus supra-subduction zone settings clearly confused the findings from Indus ophiolites. However, in this contribution, we provide arguments in favor of mid-ocean-ridge origin for Indus ophiolite. In addition, we venture to revisit the “historical contingency” model of E.M. Moores and others for Neo-Tethyan ophiolite genesis based on the available evidence and have found that our new results strongly support the “historical contingency” model.
Conference papers on the topic "Melting of oxygen-free copper"
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Kreye, H., and T. Stoltenhoff. "Cold Spraying–A Study of Process and Coating Characteristics." In ITSC 2000, edited by Christopher C. Berndt. ASM International, 2000. http://dx.doi.org/10.31399/asm.cp.itsc2000p0419.
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Abstract In cold spraying, coatings are formed by a high velocity impact of solid particles. The particles are accelerated in a supersonic gas jet at temperatures of only a few hundred degrees centigrade. In contrast to thermal spray processes no melting of the particles and negligible heating of the substrate occurs. A series of spray experiments with copper powders of different particle size ranges were performed to study the effect of various process parameters on microstructure and properties of the coatings. The coatings have been evaluated for their microstructure, density, oxygen content, hardness and bond strength. With nitrogen as process gas and a -25 +5µm powder, dense coatings were obtained within a broad range of gas inlet pressure and gas inlet temperature.
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Manoharan, Subramani, Chandradip Patel, and Patrick McCluskey. "Advancements in Silver Wire Bonding." In ASME 2017 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems collocated with the ASME 2017 Conference on Information Storage and Processing Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/ipack2017-74286.
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Silver is a leading competitor to gold and copper in fine pitch wire bonding used in the interconnection of microelectronic devices. Primary material for wire bonding has been gold, which gave way to copper in order for original equipment manufacturers to realize cost benefits. However, copper wire bonding has exhibited several reliability issues, especially in industrial and high temperature applications. Corrosion is the major problem, which was mitigated by coating the wire with palladium, which increased overall cost of production. Other concerns include harder free air ball (FAB) leading to under pad metallization cracking, smaller process window, excessive aluminum splash especially in fine pitch bonding, and lower throughput and yield arising from the hardness and stiffness of copper. Due to the above concerns, automotive, military and aerospace industries are still reluctant to fully adopt copper wire bonding. Light emitting diodes (LEDs) are also not manufactured with copper wires due to its low reflectance. Some of these industries are still using gold wire bonds in most of their packages, but are continually looking for an alternative. Silver wire bonds have good electrical and thermal conductivity, are less prone to corrosion than copper, have low melting points and comparable hardness to gold. Also, cost of silver has been shown to be similar to that of palladium coated copper wire, hence making it a good alternative. Silver wire bonding, a relatively new area of research, has attracted a lot of research focused on wire dopant material, bonding process, quality and reliability. This paper is aimed to serve as a comprehensive review of research done in this area, by summarizing the literature on silver wire bonding, establishing benefits and drawbacks over other wire bond materials and indicating reliability concerns along with failure modes and mechanisms.
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Kumar, Navin, and Debjyoti Banerjee. "Experimental Validation of Numerical Predictions for the Transient Performance of a Simple Latent Heat Storage Unit (LHSU) Utilizing Phase Change Material (PCM) and 3-D Printing." In ASME 2017 Heat Transfer Summer Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/ht2017-5045.
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Experimental validation was performed in this study to verify the efficacy of numerical models for predicting the location of solid-liquid interface in an axi-symmetric configuration during both melting and solidification in a Latent Heat Storage Unit (LHSU). Development of analytical solutions for predicting the location of the solid-liquid interface is often intractable in LHSU due to non-linear temperature distribution in the Phase Change Material (PCM). This is further complicated by the moving boundary problem with free convection within the liquid phase of the PCM. Analytical solutions available in the contemporary literature are based on simplified transient heat conduction models and often fail to reliably predict the charging and discharging time constants for LHSU with complex configurations. This study is designed with the goal of developing more sophisticated numerical models for the estimation of transient thermal performance of an LHSU with a simple configuration involving a shell and tube heat exchanger (HX). The LHSU utilized in this study is realized by integrating various types of Phase Change Materials (PCM) contained in the shell side of a HX. The LHSU is charged or discharged by pumping hot or cold fluids in the tube side of the HX (i.e., by pumping water at a fixed inlet temperature from a commercial chiller apparatus). This study enabled the characterization of the transient response of a LHSU subjected to conduction and forced convection heat transfer. The PCM used in this material was paraffin wax (PURETEMP 29). The HX in the LHSU consisted of a single pass straight tube (½ inch copper pipe) mounted within a single shell configuration. The shell was fabricated from plastic material using additive manufacturing (i.e., “3D Printing”). The temperature variation during melting and solidification of the PCM were measured at different radial and axial locations within the cylindrical shell that was mounted vertically. Temperature measurements were performed at different mass flowrate ranging from 0.004 Kg/sec to 0.007 Kg/sec for the same fluid temperature. The water bath temperatures were maintained at a constant temperature of 40°C for melting and 15°C for solidification. The experiment results show that the transient response of the LHSU for charging and discharging (i.e., time required for melting and solidification of the PCM) vary significantly. Comparison of the experimental data with analytical results (involving quasi-stationary models for phase change) demonstrate that natural convection is the dominant mode during the melting process, while conduction is the dominant mode during the solidification process.
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Lakhkar, Nikhil, Mohammad M. Hossain, Puligandla Viswanadham, and Dereje Agonafer. "Mechanical Characterization of Sn-Ag-Cu Solder With Gold Addition Under Tensile Loading." In ASME 2007 InterPACK Conference collocated with the ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ipack2007-33543.
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Lead (Pb)-free implementation for electronic assembly has created a stir in electronic packaging industry during the last five years since Europe and eastern Asian countries decided to restrict the use of lead in electronic packages. Lead (Pb) content in solders is mandated to be less than 0.2 wt % (USA) and 0.1 wt % (EU). Sn-Ag-Cu (Tin, Silver, and Copper) solder is selected as one of the options to replace tin-lead solders. This solder is a preferred option as it comes closest to tin-lead solder in terms of parameters such as melting temperature (∼217°C), wettability, cost, availability, and reliability. Various agencies like NEMI, JEIDA and IDEALS recommend Tin-rich Lead (Pb) free solders as the possible alternatives to Pb-Sn solder [1]. Addition of elements like Au, Co, Fe, Ni, etc in small quantities can affect the properties of Sn-Ag-Cu solder. It has been reported that the addition of Au in small quantities improves the properties of lead-free solder. Au has very high reactivity with Sn and also improves the wettability of solder. Au forms a β-phase with Sn at the interface. This phase is considered beneficial in terms of improving fatigue life and fracture toughness as this β phase acts as a crack arrester thereby improving its strength Addition of Au also reduces the liquidus temperature to 204 °C. In this paper we tested and compared the strength of pure Sn-Ag-Cu solder and Sn-Ag-Cu solder with Au addition and it was concluded that the strength of material increases from 50 MPa to 70 MPa under tensile loading.
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S, Aravindan, and Siddharth Tamang. "JOINING OF CU TO SS304 BY MICROWAVE HYBRID HEATING WITH NI AN INTERLAYER." In Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9813.
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The joining of dissimilar Pure Copper (Cu) to Stainless Steel (SS304) is necesilated in many industrial applications such as heat exchangers and electrical contacts. Advantages of both the materials such as high electrical conductivity of copper and better corrosion resistance of SS304 can be harnessed by way of joining both the metals. However, joining to Cu to itself or other materials is a challenge since the input heat is dissipated rapidly. Most of the conventional welding methods such as arc and gas are incompetent and unconventional methods such as Explosion Welding, EBW, Diffusion Bonding are very expensive.In this study a new economical process of joining of dissimilar metals i.e. Cu to SS304 by microwave hybrid heating is investigated. Microwave joining is made possible by applying a powder (in this work Nickel metal powder) as an interlayer and exposing to microwave surrounding the interlayer with a susceptor. In this study the interlayer of Ni powder having average size 200nm and 45μm was used. On exposure to microwave, the interlayer meal powder heats up [1] and then it promotes melting and thereby bonding to facilitate dissimilar joint. The microstructure of the joint is studied by optical microscope and scanning electron microscope. The joints formed with 200nm Ni powder were observed to have a defect free microstructure as illustrated in Fig. 1. The EDS and XRD analysis determines the formation of solid solution between Cu-Ni interface and an intermetallic compound at Fe-Ni interface. The diffusion of elements across the joint was further analyzed by EDS line scan. The hardness variation was studied by Vickers’ micro-hardness. It can be concluded that smaller size Ni heat up faster in microwave and produce stronger joint of Cu to SS304 by microwave hybrid heating. References 1. M. S. Srinath, A. K. Sharma, et al. ,Materials & Design , 2011, 32, 2685–2694
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Hassan, KM Rafidh, Mohammad S. Alam, Jing Wu, Jeffrey C. Suhling, and Pradeep Lall. "Time-Lapse Imagery and Quantitative Analysis of Microstructural Evolution of SAC305 BGA Joints During Extreme High Temperature Aging." In ASME 2020 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/ipack2020-2691.
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Abstract Solder joints provide mechanical support, electrical and thermal interconnection between packaging levels in microelectronics assembly systems. Proper functioning of these interconnections and the reliability of the electronic packages depend largely on the mechanical properties of the solder joints. Lead free solders are common as interconnects in electronic packaging due to their relatively high melting point, attractive mechanical properties, thermal cycling reliability, and environment friendly chemical properties. However, environmental conditions, such as, operating temperature, aging temperature, and aging time significantly affect these properties due to the microstructural evolution of the solder that occurs during aging. Moreover, electronic devices, sometimes experience harsh environment applications including well drilling, geothermal energy, automotive power electronics, and aerospace engines, where solders are exposed to very high temperatures from T = 125–200 °C. Mechanical properties as well as microstructural study of lead free solders at elevated temperatures are limited in literature. Previous investigations on the microstructural evolution mainly emphasized on aging at temperatures up to 125 °C. In addition, those studies were limited on investigating the coarsening of Ag3Sn IMC particles within the beta-Sn matrix. In this work, the microstructural evolutions of SAC305 (96.5Sn-3.0Ag-0.5Cu) BGA joints were investigated for different aging conditions utilizing Scanning Electron Microscopy (SEM). In particular, our approach has been to monitor aging induced microstructural changes occurring within fixed regions in selected lead free solder joints and to create time-lapse imagery of the microstructure evolution. Aging was performed at T = 125, 150, and 175 °C for several durations up to 20 days, and the topography of the microstructure of a fixed region was captured using the SEM system. This process generated several images of the microstructure as the aging progressed. We have also explored the Mechanical behavior, and aging effects of SAC305 solder joints at the extreme high testing temperature of T = 150 °C using the method of nanoindentation. To study the aging effects, solder joints were preconditioned for 0, 1, 5, 10, and 30 days at T = 125 °C in a box oven. Nanoindentation testing was then performed on the aged specimens at a test temperature of T = 150 °C to extract the elastic modulus, hardness, and creep performance of the aged material. As expected, the analysis of the evolving SAC305 BGA microstructure showed a significant amount of diffusion of silver and copper in the beta-tin matrix during aging. In addition, a very remarkable growth of copper-tin layer at solder joint and copper pad interface in the PCB side has been visualized and measured with aging time and temperature. The Quantitative analysis of the evolving microstructure showed that the particles coalesced during aging leading to a decrease in the number of particles. This caused an increase in the average diameter of the particles, which helped us to build a model to guide the growth of IMC particles at extreme high temperature aging. Nanoindentation test results also showed a huge degradation in mechanical properties with aging time increment.
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Yuan, Shuaishuai, Yiquan Li, Jinkai Xu, and Changtai Zhai. "Study on Orthogonal Micro-cutting Deformation of Oxygen-free Copper." In 2019 IEEE International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO). IEEE, 2019. http://dx.doi.org/10.1109/3m-nano46308.2019.8947407.
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Lall, Pradeep, Geeta Limaye, Sandeep Shantaram, and Jeff Suhling. "Effect of Isothermal Aging and High Strain Rate on Material Properties of Innolot." In ASME 2013 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ipack2013-73246.
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Industry migration to lead-free solders has resulted in a proliferation of a wide variety of solder alloy compositions. The most popular amongst these are the Tin-Silver-Copper (Sn-Ag-Cu or SAC) family of alloys like SAC105, SAC305 etc. Recent studies have highlighted the detrimental effects of isothermal aging on the material properties of these alloys. SAC alloys have shown up to 50% reduction in their initial elastic modulus and ultimate tensile strength within a few months of elevated temperature aging. This phenomenon has posed a severe design challenge across the industry and remains a road-block in the migration to Pb-free. Multiple compositions with additives to SAC have been proposed to minimize the effect of aging and creep while maintaining the melting temperatures, strength and cost at par with SAC. Innolot is a newly developed high-temperature, high-performance lead-free substitute by InnoRel™ targeting the automotive electronics segment. Innolot contains Nickel (Ni), Antimony (Sb) and Bismuth (Bi) in small proportions in addition to Sn, Ag and Cu. The alloy has demonstrated enhanced reliability under thermal cycling as compared to SAC alloys. In this paper, the high strain rate material properties of Innolot have been evaluated as the alloy ages at an elevated temperature of 50°C. The strain rates chosen are in the range of 1–100 per-second which are typical at second level interconnects subjected to drop-shock environments. The strain rates and elevated aging temperature have been chosen also to correspond to prior tests conducted on SAC105 and SAC305 alloys at this research center. This paper presents a comparison of material properties and their degradation in the three alloys — SAC105, SAC305 and Innolot. Full field strain measurements have been accomplished with the use of high speed imaging in conjunction with Digital Image Correlation (DIC). Ramberg-Osgood non-linear model parameters have been determined to curve-fit through the experimental data. The parameters have been implemented in Abaqus FE model to obtain full-field stresses which correlates with contours obtained experimentally by DIC.
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Waltermire, Scott W., Juekuan Yang, Deyu Li, and Terry T. Xu. "Thermal Conductivity of α-Tetragonal Boron Nanoribbons." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88347.
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Elemental boron has many interesting properties, such as high melting point, low density, high hardness, high Young’s modulus, good oxidation resistance, resulting from its complex crystalline structure from its electron-deficient nature. Boron forms complex crystalline structures according to the various arrangements of B12 icosahedra in the lattice, such as α (B12)- and β (B105)-rhombohedral and α (B50)- and β (B196)-tetragonal boron polymorphs, among others. Even though considerable materials research has been conducted over the past half century on boron and boron-based compounds, investigating their unique structures and corresponding properties, our understanding of this complex class of materials is still poor, compared to some other well-studied materials with much simpler structures such as silicon. Thermal transport studies through bulk boron have been performed mainly on β-rhombohedral and amorphous boron, because of the difficulty to grow high quality bulk α-rhombohedral boron samples [1–3]. Some efforts have been made to measure B12As2, B12P2, AlB12 samples that have an α-rhombohedral form [2,3]. There is almost no information available on α-tetragonal boron. However, Slack predicted the thermal conductivity of α-boron should be ∼200 W/m-K at room temperature, which is 1/2 that of copper. Large phonon mean free path has been predicted for α-boron (from ∼200 nm at room temperature to 6 nm at the Debye temperature), which could lead to interesting thermal transport properties for low dimensional boron structures.
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"Dislocation Density of Oxygen Free Copper with Compressive Strain Applied at High Temperature." In Mechanical Stress Evaluation by Neutron and Synchrotron Radiation. Materials Research Forum LLC, 2018. http://dx.doi.org/10.21741/9781945291678-6.
Full textReports on the topic "Melting of oxygen-free copper"
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Pritzkau, David P. Experimental Study of RF Pulsed Heating on Oxygen Free Electronic Copper. Office of Scientific and Technical Information (OSTI), February 2003. http://dx.doi.org/10.2172/812622.
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