ISO INTERNATIONAL STANDARD 17781 First edition 2017-07 Petroleum, petrochemical and natural gas industries Test methods for quality control of microstructure of ferritic/austenitic (duplex) stainless steels Industries du pétrole, de la peétrochimie et du gaz naturel - Méthodes d'essai de controle de la qualité de la microstructure des aciers inoxydables (duplex) austénitiques/ferritiques Reference number IS0 17781:2017(E) International Organization for Standardization @ IS0 2017 =ZHEJIANG INST OF STANDARDIZATION C1 5956617 Not for Resale, 2017/9/27 05:45:04 ted without license from IHS IS0 17781:2017(E) COPYRIGHT PROTECTED DOCUMENT IS0 2017, Published in Switzerland All rights reserved. Unless otherwise specified, 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 Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org Licensee-ZHEJIANG INST OF STANDARDIZAISQ 017 - All rights reserved networking permited without license from IHS IS0 17781:2017(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references 3 Terms, definitions and abbreviated terms .2 3.1 Terms and definitions .2 3.2 Abbreviated terms.... ..3 4 Sampling of test specimens ..4 4.1 General .4 4.2 Casting test blocks ..6 4.3 Welds in the as welded condition .6 5 Test methods. .7 5.1 General 7 5.2 Microstructural examination 7 5.2.1 General .7 5.2.2 Preparation of specimen 7 5.2.3 Etching of specimens 7 5.2.4 Microstructuralevaluationoftestspecimens ..8 5.3 Ferrite content measurement. 10 5.3.1 Test standard and conditions. .10 5.3.2 Acceptance criteria. .11 5.3.3 Reporting. 11 5.4 Charpy V-notch impact toughness test. 11 5.4.1 Test standard and conditions. 11 5.4.2 Acceptance criteria. .11 5.4.3 Reporting. .12 5.5 Corrosion test. .12 5.5.1 Test standard and conditions .12 5.5.2 Preparation of test specimens. .13 5.5.3 Acceptance criteria. .13 5.5.4 Reporting.... ..13 Annex A (informative) Chemical compositions of duplex stainless steels ..14 Annex B (informative) Preparation and etching for microstructural examination ..16 Bibliography ..18 Intenational organiaion@s1(Sar2.1.7 - All rights reserved iii icensee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 vithout license from IHS