The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Pierre Perrot - One of the best experts on this subject based on the ideXlab platform.
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The Fe–Zn–Al–Cr System and its impact on the galvanizing process in chromium-added zinc baths
Journal of Materials Science, 2008Co-Authors: Richard Fourmentin, Marie-noëlle Avettand-fènoël, Guy Reumont, Pierre PerrotAbstract:The zinc rich corner of the Fe–Zn–Al–Cr at 460 °C is of interest for galvanizing because Al is a usual addition element in zinc bath, whereas Cr is naturally present because it is supplied by the stainless steel roller dipping in the Zn bath during the process. Indeed, it is used to understand the formation and growth mechanisms of the solid phases during galvanizing in Al and Cr-added Zn bath. By using additional experimental results in the Al–Cr–Zn and Fe–Zn–Al–Cr Systems, the zinc rich corner of the Fe–Zn–Al–Cr System at 460 °C was determined with more accuracy. Thus, new equilibria between the liquid and quaternary phases have been pointed out, namely Al_2Cr_3 stabilized by Zn and enriched with Fe and τ_1, the latter being isotypic with δ-FeZn_9. This quaternary System was assessed with the CALPHAD method using the PARROT module of the Thermo-Calc Software. The liquid and solid solutions are desCribed by the Redlich-Kister-Muggianu equations. All the modeled phases are considered as stoichiometric in the binary Systems.
Dongho Cho - One of the best experts on this subject based on the ideXlab platform.
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concurrent spectrum sensing and data transmission scheme in a Cr System
Wireless Communications and Networking Conference, 2012Co-Authors: Woongsup Lee, Dongho ChoAbstract:We propose a spectrum-sensing and data-transmission scheme that utilizes multiple-input and multiple-output (MIMO) technology to enable the spectrum to be sensed and data to be transmitted simultaneously. By using our proposed scheme, the degradation of quality of service (QoS) that is caused by spectrum sensing can be reduced and the System throughput of a cognitive radio (Cr) System can be inCreased, while the accuracy of the spectrum sensing is unaffected. Even the Cr System transmits data during the spectrum sensing, the interference to a primary user which is caused by the Cr System will not inCrease compared to a conventional scheme. We also analyze the performance of the proposed scheme in the presence of channel estimation errors. Through performance evaluations, we show that the proposed scheme can inCrease the throughput and QoS of Cr Systems.
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WCNC - Concurrent spectrum sensing and data transmission scheme in a Cr System
2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012Co-Authors: Woongsup Lee, Dongho ChoAbstract:We propose a spectrum-sensing and data-transmission scheme that utilizes multiple-input and multiple-output (MIMO) technology to enable the spectrum to be sensed and data to be transmitted simultaneously. By using our proposed scheme, the degradation of quality of service (QoS) that is caused by spectrum sensing can be reduced and the System throughput of a cognitive radio (Cr) System can be inCreased, while the accuracy of the spectrum sensing is unaffected. Even the Cr System transmits data during the spectrum sensing, the interference to a primary user which is caused by the Cr System will not inCrease compared to a conventional scheme. We also analyze the performance of the proposed scheme in the presence of channel estimation errors. Through performance evaluations, we show that the proposed scheme can inCrease the throughput and QoS of Cr Systems.
Michael Gasik - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamic assessment of the ternary Ni–Ti–Cr System
Journal of Alloys and Compounds, 2012Co-Authors: Iikka Isomäki, Marko Hämäläinen, Michael GasikAbstract:Abstract Thermodynamic assessment of the ternary Ni–Ti–Cr System was done in this work. In previous literature only four isothermal sections and one vertical section were found so a complete assessment has been performed and several parameters have been optimized. No ternary compounds were observed in this System. The assessed interaction parameters have lead to the sections of phase diagram well correlated with the experimental points. Liquidus projection has been also calculated and the challenges in several equilibria boundaries determination have been outlined and discussed.
Richard Fourmentin - One of the best experts on this subject based on the ideXlab platform.
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The Fe–Zn–Al–Cr System and its impact on the galvanizing process in chromium-added zinc baths
Journal of Materials Science, 2008Co-Authors: Richard Fourmentin, Marie-noëlle Avettand-fènoël, Guy Reumont, Pierre PerrotAbstract:The zinc rich corner of the Fe–Zn–Al–Cr at 460 °C is of interest for galvanizing because Al is a usual addition element in zinc bath, whereas Cr is naturally present because it is supplied by the stainless steel roller dipping in the Zn bath during the process. Indeed, it is used to understand the formation and growth mechanisms of the solid phases during galvanizing in Al and Cr-added Zn bath. By using additional experimental results in the Al–Cr–Zn and Fe–Zn–Al–Cr Systems, the zinc rich corner of the Fe–Zn–Al–Cr System at 460 °C was determined with more accuracy. Thus, new equilibria between the liquid and quaternary phases have been pointed out, namely Al_2Cr_3 stabilized by Zn and enriched with Fe and τ_1, the latter being isotypic with δ-FeZn_9. This quaternary System was assessed with the CALPHAD method using the PARROT module of the Thermo-Calc Software. The liquid and solid solutions are desCribed by the Redlich-Kister-Muggianu equations. All the modeled phases are considered as stoichiometric in the binary Systems.
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Thermodynamical assessment of the Fe-Zn-Al-Cr System at 460°C
Revue de Métallurgie, 2004Co-Authors: G. Reumont, Richard Fourmentin, P. Perrot, J. Foct, S. ClaessensAbstract:In continuous hot dip galvanizing, in particular with galvannealing baths, competitive reactions occur between iron, zinc and aluminium that may be affected by other elements such as chromium. Based on thermodynamics modelling and experimental desCriptions, the zinc rich corner of the quaternary Fe-Zn-Al-Cr System is investigated at 460°C. The results obtained contribute to a better knowledge of the reactivity of steels in industrial galvanizing or galvannealing baths.
Joakim Odqvist - One of the best experts on this subject based on the ideXlab platform.
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An improved thermodynamic modeling of the Fe–Cr System down to zero kelvin coupled with key experiments
Calphad, 2011Co-Authors: Wei Xiong, Malin Selleby, Joakim Odqvist, Peter Hedström, Mattias Thuvander, Qing ChenAbstract:A thermodynamic modeling of the Fe-Cr System down to 0 K is performed on the basis of our recent comprehensive review of this binary System [W. Xiong, M. Selleby, Q. Chen, J. Odqvist, Y. Du, Evaluation of phase equilibria and thermochemical properties in the Fe-Cr System, Crit. Rev. Solid State Mater. Sci. 35 (2010) 125-152]. The model predicts a sign change for the magnetic ordering energy of mixing rather than the enthalpy of mixing in the bcc phase at 0 K. Designed key experiments are performed not only to check the validity of the present modeling but also to assist in understanding the mechanism for spinodal decomposition of the Fe-Cr alloy. Heat capacities and Curie temperatures of several Fe-rich alloys are determined between 320 and 1093 K by employing differential scanning calorimetry. The measured heat capacities are found to be in remarkable agreement with the prediction based on the present modeling. MiCrostructural patterns and frequency distribution diagrams of Cr are studied in alloys containing 26.65, 31.95, and 37.76 at.% Cr by using atom probe tomography. The observed phase separation results correspond well with our model-predicted boundary for the spinodal decomposition. Interestingly, a horn on the Cr-rich spinodal boundary is predicted below 200 K for the first time. This work demonstrates a way to bridge the ab initio calculations and CALPHAD approach.
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Phase Equilibria and Thermodynamic Properties in the Fe-Cr System
Critical Reviews in Solid State and Materials Sciences, 2010Co-Authors: Wei Xiong, Malin Selleby, Qing Chen, Joakim OdqvistAbstract:Phase equilibria and thermodynamic properties in the Fe-Cr System have been reviewed comprehensively based on experimental information and available computer simulations in different scales. The ev ...
