The Experts below are selected from a list of 835929 Experts worldwide ranked by ideXlab platform
Alain Billard - One of the best experts on this subject based on the ideXlab platform.
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contribution of enhanced ionization to the optoelectronic properties of p type nio films deposited by high power impulse magnetron sputtering
Journal of The European Ceramic Society, 2019Co-Authors: Sheng-chi Chen, Yinhung Chen, Mohammad Arab Pour Yazdi, Alain BillardAbstract:Abstract Herein, intrinsic p-type conductivity of NiO films were enhanced by high power impulse magnetron sputtering (HiPIMS) technology, where more charged Ni3+ ions are created during the deposition process. The formation of Ni3+ ions are advantageous for strengthening the p-type conductivity of NiO films. As the pulse off-Time increases from 0 μs to 3000 μs, Ni3+ concentration improves greatly, indicating the amount of Ni vacancies as well as the hole concentration significantly enhances. It confirms that HiPIMS is a preferential technology for preparing NiO films with high p-type conductivity. Especially, when pulse off-Time reaches 3000 μs, a high carrier concentration of 2.86 × 1021 cm−3 and a relatively low electrical resistivity about 0.07 Ω·cm are achieved.
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p-type cuprous oxide thin films with high conductivity deposited by high power impulse magnetron sputtering
Ceramics International, 2017Co-Authors: Sheng-chi Chen, Tung-han Chuang, Mohammad Arab Pour Yazdi, Frédéric Sanchette, Alain BillardAbstract:CuxO thin films were deposited on glass and silicon substrates by High Power Impulse Magnetron Sputtering (HiPIMS) at room temperature from a metallic copper target. The influence of pulse off-Time on the films’ structural, morphological and optoelectronic properties was investigated. It was found that the power intensity applied on the Cu target was strongly affected by pulse off-Time, which had an important impact on the films’ composition. Upon increasing the pulse off-Time from 500 μs to 3500 μs (pulse on-Time fixed at 50 μs), the films’ crystallinity as well as transmittance in the visible region both ameliorate. Meanwhile, the conductivity type changed from n-type to p-type as the films’ composition changed. When the pulse off-Time was fixed at 2000 μs, the optimal p-type conductivity of about 3 S × cm−1 was achieved, which is the highest p-type conductivity reported for Cu2O films in the last few years. The transition of the films’ conductivity type can be utilized for the fabrication of Cu2O-based p-n homojunction, and may also prove useful in developing other oxide films by using HiPIMS technology.
Sheng-chi Chen - One of the best experts on this subject based on the ideXlab platform.
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contribution of enhanced ionization to the optoelectronic properties of p type nio films deposited by high power impulse magnetron sputtering
Journal of The European Ceramic Society, 2019Co-Authors: Sheng-chi Chen, Yinhung Chen, Mohammad Arab Pour Yazdi, Alain BillardAbstract:Abstract Herein, intrinsic p-type conductivity of NiO films were enhanced by high power impulse magnetron sputtering (HiPIMS) technology, where more charged Ni3+ ions are created during the deposition process. The formation of Ni3+ ions are advantageous for strengthening the p-type conductivity of NiO films. As the pulse off-Time increases from 0 μs to 3000 μs, Ni3+ concentration improves greatly, indicating the amount of Ni vacancies as well as the hole concentration significantly enhances. It confirms that HiPIMS is a preferential technology for preparing NiO films with high p-type conductivity. Especially, when pulse off-Time reaches 3000 μs, a high carrier concentration of 2.86 × 1021 cm−3 and a relatively low electrical resistivity about 0.07 Ω·cm are achieved.
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p-type cuprous oxide thin films with high conductivity deposited by high power impulse magnetron sputtering
Ceramics International, 2017Co-Authors: Sheng-chi Chen, Tung-han Chuang, Mohammad Arab Pour Yazdi, Frédéric Sanchette, Alain BillardAbstract:CuxO thin films were deposited on glass and silicon substrates by High Power Impulse Magnetron Sputtering (HiPIMS) at room temperature from a metallic copper target. The influence of pulse off-Time on the films’ structural, morphological and optoelectronic properties was investigated. It was found that the power intensity applied on the Cu target was strongly affected by pulse off-Time, which had an important impact on the films’ composition. Upon increasing the pulse off-Time from 500 μs to 3500 μs (pulse on-Time fixed at 50 μs), the films’ crystallinity as well as transmittance in the visible region both ameliorate. Meanwhile, the conductivity type changed from n-type to p-type as the films’ composition changed. When the pulse off-Time was fixed at 2000 μs, the optimal p-type conductivity of about 3 S × cm−1 was achieved, which is the highest p-type conductivity reported for Cu2O films in the last few years. The transition of the films’ conductivity type can be utilized for the fabrication of Cu2O-based p-n homojunction, and may also prove useful in developing other oxide films by using HiPIMS technology.
Mustafa Günay - One of the best experts on this subject based on the ideXlab platform.
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Comprehensive analysis of material removal rate, tool wear and surface roughness in electrical discharge turning of L2 tool steel
Journal of Materials Research and Technology, 2020Co-Authors: Ramazan Çakıroğlu, Mustafa GünayAbstract:Abstract Electrical discharge turning (EDT) is used in the production of micro and macro cylindrical components with complex geometry, as well as ejector pins in injection molds, components of micro air turbines and pumps, micro tools or microstamping dies. On the other hand, optimization of machining parameters is crucial for machining efficiency and surface integrity of a part produced directly by EDT. Therefore, the machinability of AISI L2 steel with die-sinking EDT was comprehensively investigated by considering material removal rate (MRR), surface roughness (Ra) and tool wear rate (TWR). In addition, machining parameters named as discharge current, pulse on Time and pulse off Time were optimized by Taguchi-based grey relational analysis method. Considering the measurement results and the observations of surface morphology, the MRR, TWR and Ra increased with increasing the discharge current. However, it was detected that MRR and Ra increased while TWR decreased as the pulse on Time was increased. The increase in noncutting Time due to the pulse off Time increment led to forming of shallow craters and thus increased surface quality. The best machining parameters for die-sinking EDT of the tool steel were determined as discharge current of 3A, pulse on Time of 8 μs and pulse off Time of 6 μs. A 25.04% percentage of improvement of was achieved with the multiresponse optimization method during die-sinking EDT.
Animesh Basak - One of the best experts on this subject based on the ideXlab platform.
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Effect of wire electric discharge machining (EDM) parameters on fatigue life of Ti-6Al-4V alloy
International Journal of Fatigue, 2019Co-Authors: Alokesh Pramanik, Animesh BasakAbstract:Abstract The effect of pulse on Time, pulse off Time and wire tension were investigated on the fatigue life, crack propagation, surface roughness and machining feed during wire EDM of Ti-6Al-4V alloy. The fatigue performance of all samples is very similar at higher cyclic loading. The machining conditions affected the lower cyclic loading. Lower pulse-on Time and higher Pulse-off Time gave the longest life at lower cyclic loading. The higher wire tension gave shorter life and then remained almost constant at lower tension. It seems that the recast layer and heat affected zone are the main contributor to the fatigue performance.
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Accuracy of duplex stainless steel feature generated by electrical discharge machining (EDM)
Measurement, 2018Co-Authors: Ali Alshemary, Alokesh Pramanik, Animesh Basak, Guy LittlefairAbstract:Abstract The present paper studies different types of errors generated on the feature (cylindrical holes) which was fabricated by the wire EDM of 2205 duplex stainless steel. Different experimental parameters such as, pulse on Time, pulse off Time and wire tension on the feature as well as the contribution of these parameters on cylindricity error, circularity error and diameter error were explored. Moreover, interactions among the input parameters were also considered. It was found that the total contributions of interactions between different parameters are reasonably high for all the cases which make the modelling process very complex for cylindricity, circularity and diameter errors in term of the range of parameter considered in this investigation. Wire tension has highest contribution on cylindricity error which is lowest at high value wire tension. Pulse on Time has minor contribution on the cylindricity error and it increases with the increase of pulse on Time. Pulse of Time does not have any influence on the cylindricity error. The circularity error was lowest at medium pulse off Time and medium wire tension; and those two parameters have almost similar and highest contributions. The pulse on Time has around 14% contribution on circularity error and the medium value of it minimizes the circularity error. The input parameters such has pulse on Time, pulse off Time and wire tension have around 13%, 16% and 7% contributions respectively on diameter error which is minimized at medium pulse on Time, and low pulse off Time and low wire tension.
Ramazan Çakıroğlu - One of the best experts on this subject based on the ideXlab platform.
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Comprehensive analysis of material removal rate, tool wear and surface roughness in electrical discharge turning of L2 tool steel
Journal of Materials Research and Technology, 2020Co-Authors: Ramazan Çakıroğlu, Mustafa GünayAbstract:Abstract Electrical discharge turning (EDT) is used in the production of micro and macro cylindrical components with complex geometry, as well as ejector pins in injection molds, components of micro air turbines and pumps, micro tools or microstamping dies. On the other hand, optimization of machining parameters is crucial for machining efficiency and surface integrity of a part produced directly by EDT. Therefore, the machinability of AISI L2 steel with die-sinking EDT was comprehensively investigated by considering material removal rate (MRR), surface roughness (Ra) and tool wear rate (TWR). In addition, machining parameters named as discharge current, pulse on Time and pulse off Time were optimized by Taguchi-based grey relational analysis method. Considering the measurement results and the observations of surface morphology, the MRR, TWR and Ra increased with increasing the discharge current. However, it was detected that MRR and Ra increased while TWR decreased as the pulse on Time was increased. The increase in noncutting Time due to the pulse off Time increment led to forming of shallow craters and thus increased surface quality. The best machining parameters for die-sinking EDT of the tool steel were determined as discharge current of 3A, pulse on Time of 8 μs and pulse off Time of 6 μs. A 25.04% percentage of improvement of was achieved with the multiresponse optimization method during die-sinking EDT.
