Corrosion properties were investigated on stainless steels and Ni-base alloys in supercritical water containing 0.01mol/kg-H2SO4 at 400°C/30MPa and 400°C/60MPa as a function of oxygen concentration ranging from 3ppb to 800ppm. Corrosion rates and compositions of oxide scales indicated that Cr was basically the key element for corrosion resistance of the alloys in the testing environments. However, Fe became another major contributor to corrosion resistance when oxygen concentration of the environment was increased up to 800ppm. Oxide stability of Cr, Fe, and Ni estimated as potential-pH diagram is in good agreement with the experimental results.

Subject
Test methods, Supercritical water, Corrosion resistant alloys, Stainless alloys, Corrosion rate, Nickel based alloys, Autoclaves, Aqueous environments, Corrosion scales, Oxide scales, Oxygen, Corrosion resistance, Stainless steel
Keywords:
supercritical water, oxygen concentration, Ni-base alloy, austenitic stainless steel, sulfuric acid, oxide scale, phase stability
© 2002 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).
2002
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.