linkedintwitter
Annuaire  |  Flux RSS  |  Espace presse  |  Wiki IJL  |  Webmail  |  Videos  |    Photos   Articles scientifiques  Articles scientifiques 

Publications: Articles

Annees:  
Toutes :: 2009, 2011, 2013, 2014
Auteurs:  
Tous :: A, B, C, D, F, G, H, J, K, L, M, N, S, T 
Preferences: 
References par page: Mots clefs Voir les resumes
References

2014

Articles:

Saa, D. Kuete, Cardoso, R. P., Kosior, F., Al Taweel, A., Gries, T., Laminsi, S. and Belmonte, T.
SURFACE & COATINGS TECHNOLOGY, 255:3-7 Belmonte, T (Reprint Author), Univ Lorraine, Inst Jean Lamour, UMR CNRS 7198, F-54042 Nancy, France. Saa, D. Kuete; Kosior, F.; Al Taweel, A.; Gries, T.; Belmonte, T., Univ Lorraine, Inst Jean Lamour, UMR CNRS 7198, F-54042 Nancy, France. Saa, D. Kuete; Laminsi, S., Univ Yaounde I, Lab Chim Minerale, Yaounde 812, Cameroon. Cardoso, R. P., Univ Fed Parana, BR-81531990 Curitiba, Parana, Brazil. Gries, T.; Belmonte, T., CNRS, Inst Jean Lamour, UMR CNRS 7198, F-54042 Nancy, France.
2014
ISSN: 0257-8972

Mots clefs: RuO2; Nanostructuration; Localized growth; Micro-plasma; Afterglow

Resume: Various ruthenium dioxide nanostructures were grown locally by the oxidation of ruthenium samples with an Ar-O-2 microwave micro-afterglow operated at atmospheric pressure. A special attention was paid to the distribution of the surface temperature of the sample which evolves between 530 K and 820 K. Whatever the treatment time, the temperature and the gas composition set within the studied ranges, a general nanostructure, made of lamellae separated by 20-50 nm, is found. When the temperature rises, localized nano-sea urchins, nanotubes with square sections, nano-needles, and more complex structures are found spread over the surface. Treated surfaces were characterized by different surface diagnostics (SEM, XRD, SIMS, etc.) Finally, a growth mechanism is proposed emphasizing the role of emerging defects and stress on the appearance of localized nanostructures. (C) 2013 Elsevier B.V. All rights reserved.

Equipe: Centre de Compétences : ERMIONE informatique et calcul

2013

Articles:

Jardy, Alain, Chapelle, Pierre, Malik, Ashish, Bellot, Jean-Pierre, Combeau, Herve and Dussoubs, Bernard
ISIJ INTERNATIONAL, 53(2):213-220
2013
ISSN: 0915-1559

Resume: The present study aims to understand the melting of the consumable electrode in the VAR process and gain some insight into the influence of an ensemble arc motion on the melting behaviour. In a previous study, a 2D axisymmetric model of the heat transfer in the cathode had been developed. Using the operating parameters as model inputs, it enabled prediction of the melt rate and the evolution of the melting area. Model results were successfully compared to melt rate measurements in an industrial VAR furnace. In recent years, it has been claimed that the electric arc may not be considered as steady and axisymmetric. Our experimental investigation of the luminosity recorded during an actual VAR heat confirms that a transient 3D behaviour may take place. Therefore, a 3D version of the previous model was set up to predict the heat transfer and melting of the electrode, using the unknown ensemble arc motion as an input. The arc is assimilated to a transient distribution of energy flux density. Results evidence that the influence of the arc motion on the shape of the electrode tip can be very important. In industrial practice, the cathode tip usually remains relatively flat during melting. The shapes of the computed electrode tips enable us to propose some arc parameters which remain compatible with both the periodic behaviour of the light emitted and the flatness of the electrode.

Equipe: Centre de Compétences : ERMIONE informatique et calcul

2011

Articles:

Belmonte, T., Gries, T., Cardoso, R. P., Arnoult, G., Kosior, F. and Henrion, G.
PLASMA SOURCES SCIENCE & TECHNOLOGY, 20(2)
2011
ISSN: 0963-0252

Resume: This paper describes several specific aspects of atmospheric plasma deposition carried out with a microwave resonant cavity. Deposition over a wide substrate is first studied. We show that high deposition rates (several hundreds of mu m h(-1)) are due to localization of fluxes on the substrate by convection when slightly turbulent flows are used. Next, we describe possible routes to localize deposition over a nanometre-sized area. Scaling down atmospheric plasma deposition is possible and two strategies to reach nanometre scales are described. Finally, we study self-organization of SiO(2) nanodots deposited by chemical vapour deposition at atmospheric pressure enhanced by an Ar-O(2) micro-afterglow operating at high temperature (>1200 K). When the film being deposited is thin enough (similar to 500 nm) nanodots are obtained and they can be assembled into threads to create patterned surfaces. When the coating becomes thicker (similar to 1 mu m), and for relatively high content in HMDSO, SiO(2) walls forming hexagonal cells are obtained.

Equipe: Centre de Compétences : ERMIONE informatique et calcul

Cardoso, R. P., Belmonte, T., Kosior, F., Henrion, G. and Tixhon, E.
THIN SOLID FILMS, 519(13):4177-4185
2011
ISSN: 0040-6090

Mots clefs: Plasma-enhanced chemical vapor deposition; Hexamethyldisiloxane; Microwave assisted chemical vapor deposition; Resonant cavity; Afterglow; Post discharge

Resume: The post-discharge of a microwave resonant cavity working at atmospheric pressure is used to enhance deposition of SiOx thin films from HMDSO by chemical vapor deposition. Maximum static deposition rates are close to 150 mu m h(-1) for low power consumption per unit of coated width (similar to 100 W/cm). Dynamic deposition rates are close to 3.5 nm ms(-1). The distribution of the coating thickness is heterogeneous over an area of 150 x 90 mm(2). The influence of the main parameters of the process is systematically studied to show how the key reactions, i.e. gas phase synthesis of powders and surface deposition, are correlated. (C) 2011 Elsevier B.V. All rights reserved.

Equipe: Centre de Compétences : ERMIONE informatique et calcul

2009

Articles:

Cardoso, R. P., Belmonte, T., Noel, C., Kosior, F. and Henrion, G.
JOURNAL OF APPLIED PHYSICS, 105(9)
2009
ISSN: 0021-8979

Resume: Filamentation in an argon plasma is studied using a microwave cavity at atmospheric pressure. We show that the size and gas temperature of the filaments increase with the power absorbed by the plasma. The appearance of an additional filament occurs at specific values of the absorbed power. Each new filament appears with a smaller diameter than that of its parent filament but the sum of the diameters of all filaments evolves linearly with the absorbed power. A secondary filament emerges from a set of microfilaments created by a perturbation of the electric field (a slight increase in the incident power above a threshold value). This perturbation occurs over a larger radius than that of the parent filament. By resorting to modeling, we found that the filamentation process involves either a decrease in the effective frequency for momentum-transfer collisions, i.e., a lower electron temperature, or an increase in the electron density. We could show that a small change in the relative positions occupied by two filaments in the microwave cavity requires a strong variation in the electron temperature. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3125525]

Equipe: Centre de Compétences : ERMIONE informatique et calcul

Total:
5
Exporter au format:
BibTeX, XML