ISO INTERNATIONAL STANDARD 4491-4 Third edition 2019-04 Metallic powders Determination of oxygen content by reduction methods Part 4: Total oxygen by reduction-extraction Poudres métalliques - Dosage de I'oxygene par les méthodes de réduction Partie 4: Oxygene total par reduction-extraction Reference number ISO 4491-4:2019(E) so @ IS0 2019 IS0 4491-4:2019(E) COPYRIGHTPROTECTEDDOCUMENT @ ISO 2019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below or Iso's member body in the country of the requester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +4122 749 0111 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved IS0 4491-4:2019(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references 3 Terms and definitions 4 Principle ..1 5 Apparatus and materials ..2 6 Test portion ..3 7 Procedure .3 7.1 General ..3 7.2 Blank test and calibration .4 7.3 Test. .4 8 Expression of results ..4 8.1 Permissible tolerances ..4 8.2 Final result. .4 Test report .4 9 Annex A (informative) Examples of conditions of extraction for selected metal powders .6 @ IS0 2019 - All rights reserved iii