In this work, the corrosion behavior of NiCrBSi and AISI 410 stainless steel surfaces deposited by Plasma Transferred Arc (PTA) was investigated in a solution that simulates recycle cooling water in the oilsands extraction process. For the NiCrBSi surfaces two variations in hardness were investigated, the hardness was varied by the concentration of elements.

The microstructure of the coatings was analyzed by scanning electron microscopy (SEM) and optical microscopy (OM). The corrosion behavior of the coatings was studied by anodic polarization test (AP), potentiodynamic test (PP), linear polarization resistance (LPR) and potentiostatic test (PT). The materials in this paper are intended to be the matrix materials of metal matrix composites (MMC) for combined erosion-corrosion resistance. In this work the evaluation of the corrosion behavior of the matrix surfaces is reported.

The electrochemical characterization of the coating was carried out at different temperatures in order to establish the influence of the temperature on their corrosion behavior. There are significant effects of the microstructure of the NiCrBSi coatings on the corrosion performance; the softer coating has a higher corrosion resistance over the whole range of temperatures in comparison with the hard coating. However in both cases the higher the temperature the higher the corrosion rate as expected. After the corrosion tests, all the samples were examined by optical microscopy in order to study the corrosion mechanisms of the PTA surfaces. For the NiCrBSi hard coating more pitting and in general a more degraded surface was observed in comparison with the NiCrBSi soft coating. In the AISI 410 SS surface pitting was also identified.

Subject
Nickel coatings, Steel surfaces, Coatings, Materials, Microstructure, Precipitates, Nickel based alloys, Corrosion behavior, Corrosion resistance, Corrosion mechanisms, Erosion corrosion, Anodic polarization, Breakdown potential
Keywords:
plasma transferred arc, oilsands, corrosion, Nickel alloys, martensitic stainless steel
© 2008 Association for Materials Protection and Performance (AMPP). All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise) without the prior written permission of AMPP. Positions and opinions advanced in this work are those of the author(s) and not necessarily those of AMPP. Responsibility for the content of the work lies solely with the author(s).
2008
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.