Spraying of metallic powders by hybrid gas/water torch and the effects of inert gas shrouding

0376631 - ÚFP 2013 RIV US eng J - Journal Article
Kavka, Tetyana - Matějíček, Jiří - Ctibor, Pavel - Hrabovský, Milan
Spraying of metallic powders by hybrid gas/water torch and the effects of inert gas shrouding.
Journal of Thermal Spray Technology. Roč. 21, 3-4 (2012), s. 695-705. ISSN 1059-9630. E-ISSN 1544-1016
R&D Projects: GA MPO FR-TI2/702; GA MPO FR-TI2/561
Institutional research plan: CEZ:AV0Z20430508
Keywords : copper * tungsten * hybrid water-gas torch * plasma facing materials * plasma spraying * gas shroud
Subject RIV: BL - Plasma and Gas Discharge Physics
Impact factor: 1.481, year: 2012
http://www.springerlink.com/content/j07t3222hnv87882/fulltext.pdf

A hybrid DC arc plasma torch, combining water and gas stabilization, offers a high flexibility in plasma characteristics. These can be controlled in a wide range by the torch operational parameters, such as arc current and secondary gas flow rate. In this study, their influence on plasma spraying of tungsten and copper was investigated. To suppress the in-flight oxidation of the metals, inert gas shrouding was applied. In-flight particle diagnostics and analysis of free-flight particles and coatings was performed for spraying experiments in the open atmosphere and with argon shrouding. Both in-flight particle behavior and coating properties were found to be sensitive to the torch parameters. The application of shrouding was found to affect particle in-flight parameters, reduce the oxide content in the coatings and generally improve their properties, such as thermal conductivity. However, a different degree of these effects was observed for copper and tungsten.
Permanent Link: http://hdl.handle.net/11104/0208983