Surface engineering offers potential for eliminating metal dusting attack in several industrial applications. Prior studies suggest that alumina forming alloys provide greatly improved resistance to carbon ingress as compared to chromia forming alloys. Thermodynamic calculations of phase stability diagrams also suggest the greatly enhanced stability of alumina in high carbon, low oxygen environments, such as those conducive to metal dusting. Since alumina forming alloys are expensive and difficult to fabricate, aluminum-rich surface alloy layers produced by diffusion coating processes are technically and economically attractive. Diffusion coatings containing aluminum alone and aluminum in combination with other elements are described, including their composition and microstructural characteristics. Results of published studies in methanol reforming, ammonia plant, and a laboratory test are presented that illustrate the ability of aluminum based diffusion coatings to eliminate metal dusting corrosion. Further testing is currently underway.

Subject
Steel surfaces, Coatings, Carbides, Stainless alloys, Diffusion layers, Metal surfaces, Diffusion, Nickel based alloys, Aluminum, Metal dusting, Carbon, Stainless steel, Aluminum alloys
Keywords:
Surface engineering, aluminum diffusion coatings, metal dusting
© 2001 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).
2001
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.