Development of suspension plasma sprayed alumina coatings with high enthalpy plasma torch

0476110 - ÚFP 2018 RIV CH eng J - Journal Article
Tesař, Tomáš - Mušálek, Radek - Medřický, Jan - Kotlan, Jiří - Lukáč, František - Pala, Zdeněk - Ctibor, Pavel - Chráska, Tomáš - Houdková, Š. - Rimal, V. - Curry, N.
Development of suspension plasma sprayed alumina coatings with high enthalpy plasma torch.
Surface and Coatings Technology. Roč. 325, September (2017), s. 277-288. ISSN 0257-8972
R&D Projects: GA ČR GA15-12145S
Institutional support: RVO:61389021
Keywords : Suspension plasma spraying * Aluminium oxide * Mechanical properties * Hardness * Adhesion * Wear resistance
OECD category: Coating and films
Impact factor: 2.906, year: 2017
http://www.sciencedirect.com/science/article/pii/S0257897217306424

Deposition of aluminium oxide (Al2O3) coatings from liquid feedstocks using a high enthalpy hybrid water-stabilized plasma torch was investigated. The entire process included the optimization of spraying parameters using a commercial ready-to-spray suspension, optimization and deposition of custom-made suspensions and one solution and evaluation of mechanical properties of the most durable coatings. Acquired coating microstructures
varied from porous with typical columnar morphology to well-sintered dense structures with low porosity.
The microstructural features were clearly linked to the feedstock formulation. The most durable coating with the highest density microstructure prepared from ethanol-based suspension showed outstanding mechanical properties, e.g. high values of hardness (up to 1211 HV0.3), tensile adhesion strength (up to 51 MPa) and wear resistance (material removal rate as low as 1.94·10-5 mm3·N-1·m-1 as measured by pin-on-disc test). Moreover, deposition froma water-based solution of aluminiumnitrate resulted in deposition of highly porous coating composed predominantly of stable .alpha.-alumina phase.
Permanent Link: http://hdl.handle.net/11104/0272653