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Статті в журналах з теми "Electro spark alloy"
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Kovacik, Jaroslav, Peter Baksa, and Štefan Emmer. "ELECTRO SPARK DEPOSITION OF TiB2 LAYERS ON Ti6Al4V ALLOY." Acta Metallurgica Slovaca 22, no. 1 (March 29, 2016): 52. http://dx.doi.org/10.12776/ams.v22i1.628.
Повний текст джерелаАнотація:
<p class="AMSmaintext">The electro spark deposition (ESD) method was used to create hard wear resistant layers of TiB<sub>2</sub> ceramic onto Ti6Al4V titanium alloy. Various deposition parameters and ways and condition of deposition were employed in this study. It was showed that the TiB<sub>2</sub> layer on Ti6Al4Vcan be successfully created even using hand operating ESD equipment. Then, the microstructures of the obtained layers TiB<sub>2</sub> layer on Ti6Al4Vwere investigated using scanning electron microscope. Finally optimal conditions of the electro spark deposition were determined with respect to the obtained microstructure. It was also demonstrated that using of protective argon atmosphere is vital for creation of pore free TiB<sub>2</sub> ceramic layer on Ti6Al4V titanium alloy.</p>
2
Liu, Dongyan, Wei Gao, Zhengwei Li, Haifeng Zhang, and Zhuangqi Hu. "Electro-spark deposition of Fe-based amorphous alloy coatings." Materials Letters 61, no. 1 (January 2007): 165–67. http://dx.doi.org/10.1016/j.matlet.2006.04.042.
Повний текст джерела
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Dolgiy, Zakhar O., Wen Zhu Shao, Arcadiy V. Kozyr, and Sergey V. Martynov. "Formation of Two-Layer Heat-Resistant Coatings on TC11 Alloy by Electro-Spark Alloying Method." Advanced Materials Research 538-541 (June 2012): 175–80. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.175.
Повний текст джерелаАнотація:
Electro-spark alloying (ESA) method was used to create a coating on the surface of TC11 alloy (Ti–6.5Al–3.5Mo–1.5Zr-0.3Si wt%). The oxidation behavior of the TC11 alloy and its deposited coating was investigated in air at 700°C. The resulting structures were analyzed in great detail by metallographic analysis and by scanning electron microscopy (SEM)
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Ageev, E. V., A. S. Pereverzev, and A. A. Sysoev. "The porosity study of sintered products from electro-erosive materials of alloy Cr17, obtained in lighting kerosene." MATEC Web of Conferences 315 (2020): 01003. http://dx.doi.org/10.1051/matecconf/202031501003.
Повний текст джерелаАнотація:
The article presents the results of porosity study of sintered products from electro-erosive materials of alloy Cr17, obtained in lighting kerosene. It was shown that during the consolidation of electro-erosion materials from Cr 17 alloy by the method of spark plasma sintering, the porosity was 0.27%.
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Kumkoon, Piyapong, Chana Raksiri, and Chaiyakorn Jansuwan. "Alloy Inconel 718 by 3D Micro-Electro Discharge Machining." Applied Mechanics and Materials 590 (June 2014): 239–43. http://dx.doi.org/10.4028/www.scientific.net/amm.590.239.
Повний текст джерелаАнотація:
This article aims to show the effects of the Micro-EDM process that influences the hole taper by comparing the parameters values during micro-drilling hole on the inconel 718 material. The condition of Micro-EDM drilling spark on the surface workpiece was 300 μm of depth and 200 μm of diameter tungsten carbide electrode. The experiment was carried out under the cover of hydrocarbon, using fluid dielectric cooling. The experiment parameters included on-time duty factor, off-time, voltage, frequency, and current, respectively. The experiment, it was found that the hole taper an immense effect on the machinability of drilling the workpieces, cause melting and recasting in the spark area, making a decrease in the ability of debris removal. Moreover, the experiment result, the tapered workpiece showed a minimized is 16.87 s, when using parameters at current 32 mA, frequency 150 Hz, and voltage 110 v, respectively. The optimal parameters to affected minimum hole taper is 0.195 degree, when using parameters at current 32 mA, frequency 130 Hz, and voltage 110 v, respectively.
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Xu, Yong, Z. N. Guo, Guan Wang, and Y. J. Zhang. "CuCr1 Alloy Surface Hardening via Ultrasonic Assisted Electro-Spark Deposition." Advanced Materials Research 279 (July 2011): 33–38. http://dx.doi.org/10.4028/www.scientific.net/amr.279.33.
Повний текст джерелаАнотація:
Resistance Spot Welding (RSW) is a widely used technology. And the rapid wear is the main reason for the short life of RSW electrodes. To improve electrode life during RSW, a novel ultrasonic-aided electro-spark deposition technology (UESD) and device are proposed in this paper. The WC metallurgical bond coating was fabricated on the surface of CuCr1 electrodes by UESD, and some experimental results were also analyzed. Moreover, the surface morphology of WC coating was studied by SEM and the quality of coating wear resistance was analyzed through experimental method. This study provides a novel way to extend the life of common moulds and RSW electrodes.
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Wang, Ming Wei, Wen Xin, Xiu Jun Zhao, Qin Yi Ma, and Shu Li. "Characterizations of Electrospark Deposition TA2 Alloy Coating on 7075 Aluminum Alloy Surface." Advanced Materials Research 821-822 (September 2013): 873–76. http://dx.doi.org/10.4028/www.scientific.net/amr.821-822.873.
Повний текст джерелаАнотація:
Electro-spark deposition (ESD) is a microwelding process that utilizes short duration of electrical pulses to deposit electrode materials to a metallic substrate. In this paper, taking TA2 bar as electrode, a deposition layer of thickness up to 40μm was built up to on 7075 aluminum alloy substrate by means of ESD. The deposition layer is metallurgical bonded to the substrate. The microstructure, phase composition, and micro-hardness of TA2 coating were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and micro-hardness test. The microstructure of the coating was mainly composed of TiN phase, Al3Ti phase, AlN phase and Al phase. Its micro-hardness reached 295 HV0.05, about 2 times as high as that of the substrate. The hardness at the cross-section of the entire deposition layer showed a gradient distribution.
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Zhang, Chun Hua, Yu Xi Hao, Lin Qi, Fang Hu, Song Zhang, and Mao Cai Wang. "Preparation of Ni-Base Alloy Coatings on Monel Alloy by Laser Cladding." Advanced Materials Research 472-475 (February 2012): 313–16. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.313.
Повний текст джерелаАнотація:
Abstract. The paper presents the results of a study concerned with the surface hardening of Inconel 625 alloys and Ni-base alloy powder on Monel alloy by electro spark deposition and laser cladding processes. The microstructure, the phase composition and the microhardness of samples are investigated by SEM, EDS, XRD and microhardness instrument. It is shown that, the matrix phase is mainly made up of dendritic structure (γ-Ni), interdendritic eutectic phase (Ni3(B,Fe,Si)) and some precipitates (Cr7C3, Cr23C6). Additional, the microhardness of laser cladding layer can be substantially increased, duo to formation of precipitates.
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Li, Zhengwei, Wei Gao, and Yedong He. "Protection of a Ti3Al–Nb alloy by electro-spark deposition coating." Scripta Materialia 45, no. 9 (November 2001): 1099–105. http://dx.doi.org/10.1016/s1359-6462(01)01146-0.
Повний текст джерела
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Khardikov, S. V., A. N. Novikov, and A. E. Ageeva. "The porosity study of sintered products from electro-erosive materials of alloy Cr13, obtained in butyl alcohol." MATEC Web of Conferences 329 (2020): 02020. http://dx.doi.org/10.1051/matecconf/202032902020.
Повний текст джерелаАнотація:
The article presents the results of a study of the porosity of sintered products from alloy X13 electroerosive materials obtained in butyl alcohol. It is shown that when hardening electroerosive materials from alloy X13 by the method of spark plasma sintering, the porosity was 3.347%.
Дисертації з теми "Electro spark alloy"
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Яременко, Денис Олегович. "Формування функціональних покриттів на сталі 40Х електроіскровим легуванням хромом та ніобієм". Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/43127.
Повний текст джерелаАнотація:
Об’єкт дослідження – поверхневі шари сталі 40Х, отримані електроіскровим легуванням анодами хромом та ніобієм на повітрі.
Мета роботи – встановити вплив послідовності ЕІЛ хромом і ніобієм на мікроструктуру, фазовий склад і мікротвердість поверхневих шарів сталі 40Х.
Методи дослідження – гравіметричний, мікроструктурний, мікродюрометричний та рентгенофазовий. Показана можливість формування зміцнених покриттів (мікротвердістю 9,5 ГПа – 14,5 ГПа і товщиною 20 мкм – 35 мкм) електроіскровим легуванням Cr та Nb сталі 40Х при різній послідовності нанесення матеріалів анодів.
Встановлено вплив нанесення хрому та ніобію під час електроіскрового легування сталі 40Х на поверхневу мікротвердість, фазовий склад та мікроструктуру модифікованого шару.
Виявлено, що найбільшу мікротвердість (14,5 ГПа) має легований шар після ЕІЛ сталі Nb, а найбільшу товщину (35 мкм) – при пошаровому ЕІЛ у послідовності Cr- Nb.
Практичне значення: одержані в роботі результати та з’ясовані закономірності формування структури та характеристик модифікованих шарів під час електроіскрового легування можуть бути застосовані для подовження строку експлуатації деталей машин та механізмів.The object of the study is the surface layers of 40X steel, obtained by electrospark doping with chromium and niobium anodes in air. The aim of the work is to establish the influence of EIL chromium and niobium sequences on the microstructure, phase composition and microhardness of 40X steel surface layers. Research methods - gravimetric, microstructural, microdyurometric and X-ray phase. The possibility of forming reinforced coatings (microhardness 9.5 GPa – 14.5 GPa and thickness 20 μm – 35 μm) by electrospark alloying of Cr and Nb steel 40X with different sequence of anode materials application is shown. The influence of chromium and niobium deposition during electrospark alloying of 40X steel on the surface microhardness, phase composition and microstructure of the modified layer was established. It was found that the alloyed layer has the highest microhardness (14.5 GPa) after the EIL of Nb steel, and the greatest thickness (35 μm) - with layered EIL in the Cr-Nb sequence. Practical significance: the results obtained in the work and the regularities of the formation of the structure and characteristics of the modified layers during electrospark alloying can be used to extend the service life of machine parts and mechanisms.
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Зінченко, І. Д. "Дослідження структури та властивостей захисних покриттів на алюмінієвих сплавах". Master's thesis, Сумський державний університет, 2020. https://essuir.sumdu.edu.ua/handle/123456789/81384.
Повний текст джерелаАнотація:
У роботі проведені дослідження властивостей алюмінієвих сплавів після нанесення на них захисних покриттів методом електроіскрового легування.
В наш час досить широкого застосування набули алюмінієві сплави, однак, алюміній і його сплави володіють недостатньою зносостійкістю. Для цього застосовують методи модифікації поверхні, які формують на поверхні сплавів захисний шар. Перспективним напрямком модифікації поверхні алюмінієвих сплавів є електроіскрове легування (ЕІЛ). Істотними перевагами електроіскрового легування є: висока адгезія покриття з основою, можливість локальної обробки поверхні, відсутність необхідності в попередній підготовці поверхні і екологічність процесу. Тому актуальним є дослідження особливостей формування на алюмінієвих сплавах захисних шарів, що володіють достатньою суцільністю та зносостійкістю.
В роботі показано, що при низькій енергії імпульсів J < 0,8 Дж покриття на алюмінієвому сплаві Д1 з приростом шару не утворюються через сильний знос матеріалу з зразка (катода), поверхня зразка тільки модифікується. Приріст шару відбувається при підвищенні енергії імпульсів до J > 0,8 Дж. Крім того, в покритті виявлені мікро - та нанонитки з оксидів олова, що утворюються в результаті дії електромагнітних сил. Показано, що мікро - та нанонитки переносяться на поверхню зразка, утворюючи покриття зі зміненими властивостями. Отримані мікро - та нанонитки грають роль «арматури», що зв'язує покриття в шар і сприяє його збільшенню, що дає можливість використання таких покриттів для відновлення зношених деталей.У роботі проведені дослідження властивостей алюмінієвих сплавів після нанесення на них захисних покриттів методом електроіскрового легування. В наш час досить широкого застосування набули алюмінієві сплави, однак, алюміній і його сплави володіють недостатньою зносостійкістю. Для цього застосовують методи модифікації поверхні, які формують на поверхні сплавів захисний шар. Перспективним напрямком модифікації поверхні алюмінієвих сплавів є електроіскрове легування (ЕІЛ). Істотними перевагами електроіскрового легування є: висока адгезія покриття з основою, можливість локальної обробки поверхні, відсутність необхідності в попередній підготовці поверхні і екологічність процесу. Тому актуальним є дослідження особливостей формування на алюмінієвих сплавах захисних шарів, що володіють достатньою суцільністю та зносостійкістю. В роботі показано, що при низькій енергії імпульсів J < 0,8 Дж покриття на алюмінієвому сплаві Д1 з приростом шару не утворюються через сильний знос матеріалу з зразка (катода), поверхня зразка тільки модифікується. Приріст шару відбувається при підвищенні енергії імпульсів до J > 0,8 Дж. Крім того, в покритті виявлені мікро - та нанонитки з оксидів олова, що утворюються в результаті дії електромагнітних сил. Показано, що мікро - та нанонитки переносяться на поверхню зразка, утворюючи покриття зі зміненими властивостями. Отримані мікро - та нанонитки грають роль «арматури», що зв'язує покриття в шар і сприяє його збільшенню, що дає можливість використання таких покриттів для відновлення зношених деталей.
The study of the properties of aluminum alloys after the application of protective coatings by electrospark alloying. Nowadays, aluminum alloys are widely used, however, aluminum and its alloys have insufficient wear resistance. To do this, use surface modification methods that form a protective layer on the surface of the alloys. A promising direction of surface modification of aluminum alloys is electrospark alloying (EIL). Significant advantages of electrospark alloying are: high adhesion of a covering with a basis, possibility of local processing of a surface, absence of need for preliminary preparation of a surface and environmental friendliness of process. Therefore, it is important to study the peculiarities of the formation of protective alloys on aluminum alloys, which have sufficient continuity and wear resistance. It is shown that at low pulse energy J <0.8 J coatings on aluminum alloy D1 with layer increment are not formed due to strong wear of the material from the sample (cathode), the surface of the sample is only modified. The increase of the layer occurs when the pulse energy increases to J> 0.8 J. In addition, micro - and nanowires of tin oxides formed as a result of electromagnetic forces are detected in the coating. It is shown that micro - and nanowires are transferred to the surface of the sample, forming a coating with altered properties. The obtained micro - and nanowires play the role of "reinforcement", which binds the coating to the layer and contributes to its increase, which allows the use of such coatings to restore worn parts.
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Vracar, Radivoje. "Développement de matériaux Mg2Si1-xSnx de type n et p pour applications thermoélectriques dans la gamme de température 300-600 °C." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI109.
Повний текст джерелаАнотація:
Des alliages Mg-Si-Sn et Mn-Si, de type n et p respectivement, ont été étudiés pour des applications thermoélectriques dans la gamme de température 20-600 °C. Afin de fabriquer des matériaux denses, un procédé en deux étapes a été développé. La première étape est la fabrication des poudres mères par mécano-synthèse. La deuxième étape consiste en la densification des diverses poudres par la méthode de frittage SPS.En optimisant les conditions opératoires, un ZT de 1.2 a été obtenu à 500 °C pour un matériau de type n de composition Mg2Si0.4Sn0.6. En incorporant de surcroit une faible fraction volumique de nanoparticules de la famille des composés Half-Heusler, il a été possible de fabriquer un matériau présentant au final un ZT de 1.4 à 500 °C. Des liens forts ont été établis entre les paramètres expérimentaux de fabrication, les propriétés thermoélectriques et la microstructure des matériaux frittés (utilisation de la microscopie électronique en transmission).Concernant les études sur le matériau MnSi1.75 de type p, les résultats obtenus ne sont que préliminaires. Néanmoins, en contrôlant là aussi les paramètres de fabrication, un ZT de 0.45 à 575 °C a été obtenu sur un matériau frittéN and P type Mg-Si-Sn and Mn-Si alloys have been investigated for thermoelectrical applications in the 20-600 °C temperature range. To manufacture dense sintered samples, only two steps have been used: mechanical-alloying followed by spark plasma sintering.By optimizing the processing conditions it was possible to obtain an n-Type Mg2Si0.4Sn0.6 material exhibiting a ZT parameter of 1.2 at 500 °C. By adding Half-Heusler nanoparticles to a Mg2Si0.4Sn0.6 matrix, it was shown that the ZT parameter is increased to 1.4 at 500 °C. Then strong links have been established between the processing parameters, the thermoelectrical properties and the sintered microstructure (use of transmission electron microscopy).The investigations performed on a p-type MnSi1.75 material are only preliminary ones. Nonetheless, always by tailoring the processing conditions, it was possible to obtain a sintered material exhibiting a ZT parameter of 0.45 at 575 °C
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Kubíček, Antonín. "Vliv podmínek mechanického legování na kontaminaci práškových směsí a bulk materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-416663.
Повний текст джерелаАнотація:
This thesis deals with the influence of process parameters on the contamination level of powder materials produced by mechanical alloying (MA) technology. For this purpose austenitic stainless steel 316 L and equiatomic CoCrFeNi high-entropy alloy (HEA) were prepared by high-energy ball milling. Both materials were milled in argon and nitrogen atmospheres from 5 to 30 hours. Spark plasma sintering method (SPS) was then used for consolidation of chosen powder samples. Chemical analysis of contamination within MA was carried out using combustion analysers for determination of carbon, oxygen, and nitrogen contents after different lengths of milling. Also differences in chemical composition of powder and corresponding bulk samples were measured. The microstructure analysis using scanning electron microscopy (SEM) of both powder and bulk materials was executed with focus on oxide and carbide presence and dispersion. Increasing content of carbon with increasing milling time was observed across all measured samples. This contamination is attributed to using milling vial made of tool steel AISI D2 (containing 1,55 wt. % of carbon). Increase of carbon content within consolidation using SPS was also observed. Milling of specimens using N2 as milling atmosphere caused higher contamination level in both AISI 316 L and HEA compared to milling in argon.
Частини книг з теми "Electro spark alloy"
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Hao, Jian Jun, Zhi Guo Pu, Hong Jie Liu, and Jian Guo Zhao. "Reactive Electric Spark Deposition of Ti(CN)–Based Ceramics Coating on Titanium Alloy Substrate." In High-Performance Ceramics V, 1313–15. Stafa: Trans Tech Publications Ltd., 2008. http://dx.doi.org/10.4028/0-87849-473-1.1313.
Повний текст джерела
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Vizureanu, Petrică, Manuela-Cristina Perju, Dragoş-Cristian Achiţei, and Carmen Nejneru. "Advanced Electro-Spark Deposition Process on Metallic Alloys." In Advanced Surface Engineering Research. InTech, 2018. http://dx.doi.org/10.5772/intechopen.79450.
Повний текст джерела
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Gaitonde, V. N., S. R. Karnik, and J. Paulo Davim. "Application of Particle Swarm Optimization for Achieving Desired Surface Roughness in Tungsten-Copper Alloy Machining." In Computational Methods for Optimizing Manufacturing Technology, 144–61. IGI Global, 2012. http://dx.doi.org/10.4018/978-1-4666-0128-4.ch006.
Повний текст джерелаАнотація:
The tungsten-copper electrodes are used in the manufacture of die steel and tungsten carbide workpieces due to high thermal and electrical conductivity of copper, spark erosion resistance, low thermal expansion coefficient, better arc-resistance, non-welding, and high melting temperature of tungsten. Since a tungsten-copper electrode is more expensive than traditional electrodes; there is a need to study the machinability aspects, especially the surface roughness of turned components, which has a greater influence on product quality. This chapter deals with the application of response surface methodology (RSM) for the development surface roughness model for turning of tungsten-copper alloy. The experiments were planned as per full factorial design (FFD) with cutting speed, feed rate, and depth of cut as the process parameters. The proposed surface roughness model was employed with particle swarm optimization (PSO) to optimize the parameters. PSO program gives the minimum values of surface roughness and the corresponding optimal machining parameters.
Тези доповідей конференцій з теми "Electro spark alloy"
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Penyashki, T., G. Kostadinov, and M. Kandeva. "INVESTIGATION OF THE PROPERTIES OF NON-TUNGSTEN ELECTRO-SPARK COATINGS ON HIGH SPEED STEEL." In BALTTRIB. Aleksandras Stulginskis University, 2017. http://dx.doi.org/10.15544/balttrib.2017.08.
Повний текст джерелаАнотація:
In this work contactless local electro spark deposition (LESD), has been used to received wear resistant coatings from hard alloys based of ТiC, TiN, TiCN onto high speed steel HS6–5–2. The influence of the operating electric parameters and the electrode materials on the roughness, thickness, microhardness, phase composition, and on the structure of resulting coatings was studied. The impact of different electrode materials on the quality characteristics, the composition and structure of the resulting coatings has been found. The technological parameters of the LESD process for the formation of coatings with a predefined roughness, thickness, composition and structure has been determined.
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Lin, H. T., M. P. Brady, M. D. Kass, T. J. Theiss, N. Domingo, I. Levina, and J. Lykowski. "Characterization and Mitigation of Spark Plug Electrode Erosion in Natural Gas and Automotive Engine Applications." In ASME 2007 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/icef2007-1697.
Повний текст джерелаАнотація:
Microstructural characterization was conducted for laboratory gasoline and natural gas reciprocating engine tested spark plug electrodes made from a range of model, developmental, and commercially available electrode alloys. These alloys were selected to explore the effects of differing electrode alloy thermal, chemical, and mechanical characteristics on erosion resistance, and were tested with and without sparking surface alloy insert pads (platinum group and novel Cr-based alloys). Extensive internal oxidation and cracking were observed in both gasoline and natural gas engine tests, indicative of an inherent degree of susceptibility of currently-used electrode materials when heated to elevated temperatures, no matter what the ignition conditions. Highly-alloyed heat-resistant alloys with excellent oxidation resistance in many high-temperature environments suffered from increased rates of erosion, as the gains in oxidation resistance appear to have been offset by hotter running temperatures resulting from decreased electrode alloy thermal conductivity. Promising early results were obtained with a novel Cr-6MgO-0.5Ti-0.3La2O3 insert pad electrode alloy, investigated as an alternative to Pt- or Ir- base alloys, which showed little erosion and good resistance to cracking and oxidation.
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Shirguppikar, Shailesh, and Maharudra Patil. "Performance Analysis of Multi Wall Carbon Nanotubes (MWCNT) Coated Tool Electrode During Machining of Titanium Alloy (Ti6Al4V)." In ASME 2020 15th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/msec2020-8224.
Повний текст джерелаАнотація:
Abstract Electric Discharge Machining (EDM) is one of the leading non-conventional machining processes used to machine hard-to-cut materials in wide range of industrial, biomedical, automotive, defense and aerospace applications. EDM is a controlled spark generation process, which is usually used for machining of difficult to cut materials. In this study, experiments were performed on Titanium Alloy (Ti6Al4V) using thin-film multi-wall Carbon Nanotubes (MWCNT) coated electrode and uncoated aluminum electrodes. Morphological and structural investigations of MWCNT coating were performed using Scanning transmission electron microscope (TEM) and Raman spectroscopy. All experiments were designed with Taguchi’s L16 orthogonal array. Each experiment performed under different condition of current, gap voltage and pulse on time. MRR, TWR, SR and OC are studied for each experiment. It was observed that MWCNT coated electrode gives better surface roughness, higher material removal rate, and lower tool wear rate. The experimental result showed that MRR increased by 14.15%, tool wear rate decreased by 23.40%, surface roughness reduced by 22.14 % and overcut reduced by 23.43 % respectively as compared to uncoated aluminum electrodes. All performance responses improved with thin-film MWCNT coated electrode due to magnificent electrical conductivity and chemical stability of CNT. Analysis of Variance (ANOVA) carried out to understand significant process parameters and its contribution in mentioned response variables. Multi-Wall CNT shows better results at high temperature and prevents the tool wear rate. The surface roughness of Ti6Al4V improved with MWCNT coated electrode and it was evident with scanning electron microscope (SEM) images of workpiece. Comparative study of coated and non-coated gives new development of novel electrode tool for electric discharge machining processes.
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Richards, Roger K., David M. Layton, Hua-Tay Lin, and Michael P. Brady. "Characterization of Erosion Mechanisms of Natural Gas Engine Spark Plugs." In ASME 2004 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/icef2004-0875.
Повний текст джерелаАнотація:
J-type spark plugs composed of Ni-base alloy electrodes with a pure Ir tip in the center electrode and a Pt-W alloy tip in the ground electrode were examined as-manufactured and after use in natural gas reciprocating engines by spectroscopic and metallurgical techniques. The spectroscopic examination indicated Ni emission from the Ni alloy electrodes in new plugs, but a strong Ca signal in engine used plugs. This was confirmed by metallurgical examination, which showed the presence of Ca containing glassy oxide phase(s) (with the electrode alloy components) in the used spark plug electrodes. Intergranular cracking was observed on the Ir and Pt-W alloy electrode insert tips. The interface between the Pt-W insert and the Ni alloy ground electrode also became a site for extensive cracking and oxidation during service. These oxidation/corrosion and metallurgical issues may represent a significant component of the wear mechanism of these plugs in natural gas engines.
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Kumar, Sanjeev. "An Experimental Study of the Phenomenon of Surface Alloying by EDM Process Using Inconel Tool Electrode." In ASME 2013 International Manufacturing Science and Engineering Conference collocated with the 41st North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/msec2013-1014.
Повний текст джерелаАнотація:
Electrical Discharge Machining (EDM) has emerged as a very important machining process due to its numerous advantages. It is extensively used by the die and toolmaking industry for the accurate machining of complex internal profiles. Although EDM is essentially a material removal process, it has been used successfully for improving the surface properties of the work materials after machining. As the dissolution of the electrode takes place during the process, some of its constituents may alloy with the machined surface under appropriate machining conditions. Additive powders in the dielectric medium may form part of the plasma channel in the molten state and produce similar alloying effect. The breakdown of the hydrocarbon dielectric under intense heat of the spark contributes carbon to the plasma channel. Sudden heating and quenching in the spark region also alters the surface properties. This paper reports the results of an experimental study into electrical discharge machining of H13 hot die steel with Inconel (an alloy of chromium, nickel and iron) tool electrode under machining conditions favouring high electrode wear. The results show improvement in micro-hardness after machining by as much as 88%. Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analysis of the machined surfaces show transfer of chromium and nickel from the tool electrode. Both these elements form intermetallic compounds as well as solid solution with iron and strengthen it. It was found that percentage of chromium increased from 5.39% to 6.52% and that of nickel increased from 0.19% to 4.87%. The favourable machining conditions for surface alloying were found to be low value of peak current, shorter pulse on-time, longer pulse off-time and negative polarity of the tool electrode.
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Ashwath, Pazhani, M. Anthony Xavior, Tushar Nigam, Anubhav Goel, and Mohit Rathi. "Effect of Recast Layer on the Strength Properties of the Spark Electric Discharge Machined Aluminium Alloy Composites." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70104.
Повний текст джерелаАнотація:
The objectives of this research work are to determine the influence of effect of spark electric discharge machine on the recast layer and indeed the strength properties of the AA 6061-Graphene composites. The green compacts were subjected to microwave sintering at 550 °C for 30 minutes. The sintered samples are then hot extruded at 300 °C to flat plates and air cooled later. The extruded samples are subjected to mechanical characterization for density, hardness and tensile strength. Further, spark EDM process is used to machine the extruded samples. The SEDM processed samples with the aluminium alloys 6061-Gr composites compared with the as extruded condition. The hardness studies on the samples are carried out using Rockwell hardness testing machine with B scale as per standards, Tensile strength studies are carried out in Instron Universal Testing Machine with a standard strain rate of 0.75 mm/min. Recast layer of the SEDM samples is studied using HR-SEM and the thickness of the recast layer is recorded. The influence of the recast layer thickness on the tensile strength the extruded composite is studied. The surface roughness and material removal rate (MRR) of the extruded composites after the SEDM process also studied in correlation with the strength properties.
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Koshuro, Vladimir A., and Aleksandr A. Fomin. "Microtexturing and nanostructuring of the surface of titanium and its alloy using spark alloying with tantalum and subsequent oxidation." In 2014 Tenth International Vacuum Electron Sources Conference (IVESC). IEEE, 2014. http://dx.doi.org/10.1109/ivesc.2014.6892016.
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Shaffer, James, and Omid Askari. "A New Electrode Design for Constant Volume Combustion Chamber." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-24168.
Повний текст джерелаАнотація:
Abstract The current method of achieving center chamber ignition in the Plasma Combustion Research Laboratory’s (PCRL) Constant Volume Combustion Chamber (CVCC) utilizes either a standard or modified spark plug. The standard spark plug achieves a representation of side wall ignition (similar to a combustion engine) while modified sparkplugs have an extended electrode to allow for a center camber ignition. Two of these modified spark plugs are placed on both sides of the chamber and can effectively seal and isolate the chamber from the electrode. However, the process of welding electrode material to the spark plug is time consuming and requires a large number of modified electrodes to effectively test multiple different spark gap sizes. Also, the process of cleaning the electrode after experimentation shortens the electrode over time with no method of compensation other than creating a new electrode. The new electrode design aims to reduce the structural weakness by removing the welded joint as well as allowing for linear adjustment between testing while remaining firm during testing. The new design presented utilizes high-temperature epoxy, ceramic and grafoil seals to make adjustments easy and precise. The design was analyzed, prior to building and testing, based on the stress induced from the sealant, the total rated voltage, the rated temperature, and the fracture stress of the ceramic material. The stress induced in the electrode device was analyzed with FEA and the results were found to be within the limits of the material in terms of the compressive and fracture strength. The maximum voltage was found to be around 30 kV. The design is tested with 3 different electrode sizes where the largest electrode of 1.3 mm (0.05 in) has the same diameter as the current experimental set up. Two smaller electrodes 1 mm and 0.5 mm (0.04 in and 0.02 in) are tested as well to show the range and capabilities of the new system. The voltage and current data of the new and old system are compared and are found to be statistically similar within a 90 percent confidence level. The new electrodes is also compared to the previous system in terms of electrical resistance, the peak power each system can provide to the plasma, the visual shape and duration of the plasma through high speed photography. The range of operation for a successful design includes pressures from 20 mTorr to 40 atm, temperatures up to 280 C, and voltages up to 25 kV.
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James, Erik, Jamil Grant, Michael Alberter, Nastassja Dasque, Cynthia Price, and William J. Craft. "Nickel-Titanium Shape Memory Alloy Motors and Electromechanical Devices." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15119.
Повний текст джерелаАнотація:
Shape memory alloys (SMA) have been an extensively used material for actuators in micro-electromechanical systems (MEMS) because actuation force and displacement are greatest in SMA amongst many actuator materials [1]. Of the alloys currently available for SMA actuators, the most popular system is Nitinol (or NiTi) due to its good oxidation resistance, reversible martensitic transformation, broad range of transformation temperatures (from -100 - 100 °C), and specific power density [2]. Current commercially available SMA wire has easily achieved no-load strain of 5% with medium gage SMA wires demonstrating an axial force capacity of 2 Newtons or more. While the potential use of SMA materials in a thermal-electric motor has been documented beginning in the 1980's, there are a number of new allows and fatigue-resistant materials that may lead to more general designs with a wide range of motions and applications. Shape memory alloys are a special type of material that exhibit two unique properties, pseudo-elasticity and shape memory effect (SME). SMA undergoes SME because of martensitic or diffusionless transformation where each atom has a slight displacement, creating observable changes throughout the structure as the allow changes states. This alloy has the ability, once heated, to return to its parent austenite phase where it exists at higher symmetry. Upon cooling, the material returns to one of many lower symmetry martensitic phases. This thermal cycle is shown in Figure 1. [3,4]. It is even possible for many variants of martensite to be present in the same material. Pseudo-elasticity is a rubber-like flexibility that allows the SMA to be contorted for a variety of purposes. Once contorted, the application of heat will cause the alloy to undergo martensitic transformation. Upon completion of the cycle, the alloy will have returned to its original shape. The development of SMA-based electromechanical devices delivers traditional mechanical motion with non-traditional methods. Rather than electromagnetic components rotating about a central axis to produce power, the rotary SMA motor utilizes contracting elements, and mush as spark ignition rotary engine, it can be designed to produce angular motion. Motion is accomplished with sequenced electrical signals sent across each element mounted between an eccentric crank. Rotary motion is produced during the power portion of the cycle for specific SMA elements under the application of an electrical signal. Based on this concept, our team developed a demonstration model with four active elements. We have demonstrated rotary motion of the device for an extended period of time, and we believe that macro-scale models can reduce the concept substantially and perhaps to the MEMS level.
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Johnson, Derek, Marc Besch, Nathaniel Fowler, Robert Heltzel, and April Covington. "Evaluation of Spark Plug and Timing Configurations on the Fuel Consumption, Combustion Stability, and Emissions of a Large-Bore, Two-Stroke, Natural Gas Engine." In ASME 2016 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icef2016-9454.
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Emissions compliance is a driving factor for internal combustion engine research pertaining to both new and old technologies. New standards and compliance requirements for off-road spark ignited engines are currently under review and include greenhouse gases. To continue operation of legacy natural gas engines, research is required to increase or maintain engine efficiency, while reducing emissions of carbon monoxide, oxides of nitrogen, and volatile organic compounds such as formaldehyde. A variety of technologies can be found on legacy, large-bore natural gas engines that allow them to meet current emissions standards — these include exhaust after-treatment, advanced ignition technologies, and fuel delivery methods. The natural gas industry uses a variety of spark plugs and tuning methods to improve engine performance or decrease emissions of existing engines. The focus of this study was to examine the effects of various spark plug configurations along with spark timing to examine any potential benefits. Spark plugs with varied electrode diameter, number of ground electrodes, and heat ranges were evaluated against efficiency and exhaust emissions. Combustion analyses were also conducted to examine peak firing pressure, location of peak firing pressure, and indicated mean effective pressure. The test platform was an AJAX-E42 engine. The engine has a bore and stroke of 0.216 × 0.254 meters (m), respectively. The engine displacement was 9.29 liters (L) with a compression ratio of 6:1. The engine was modified to include electronic spark plug timing capabilities along with a mass flow controller to ensure accurate fuel delivery. Each spark plug configuration was examined at ignition timings of 17, 14, 11, 8, and 5 crank angle degrees before top dead center. The various configurations were examined to identify optimal conditions for each plug comparing trade-offs among brake specific fuel consumption, oxides of nitrogen, methane, formaldehyde, and combustion stability.