Structure of alumina oxide coatings deposited by impulse plasma method

Al2O3 coatings were produced by the LPD method with the use of solid precur sors of aluminium oxide. The coatings were deposited on non-heated substrat es and on substrates heated from an external heat source at various geometr ies of the substrate/impulse plasma stream arrangement. Depending on the te chnological variant employed, the coatings obtained were composed of metast able or stable monotropic Al2O3 phases. The process parameters also affecte d the morphology of the coatings. The IR, RS and XPS examinations of the at omic structure of the coatings, performed in the present study and in earli er investigations, have shown that the aluminium oxide coatings deposited f rom impulse plasma have a nanocrystalline amorphous structure. The phase co mposition and morphology of the coatings can be modified by heating the sub strate in a stationary way during the IPD process, to a temperature of 500 K. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.