ISO INTERNATIONAL STANDARD 4938 Second edition 2016-02-01 Steel and iron Determination of nickel content Gravimetric or titrimetric method Aciers et fontes - Détermination du nickel - Méthode gravimétrique ou titrimétrique Reference number ISO 4938:2016(E) ISO International Organization for Standardization see=ZHEJIANG INST OF STANDARDIZATION C1 5956617 @ISO2016 vided by IHS under No reproduction or networking permitted without license from IHS IS0 4938:2016(E) COPYRIGHTPROTECTEDDOCUMENT IS0 2016, 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 [email protected] www.iso.org Licensee-ZHEJIANG INST OF STANDARDIZAISQ 0d6 - All rights reserved HS und Not for Resale, 2016/4/22 08:03:50 networking permited without license from IHS IS0 4938:2016(E) Contents Page Foreword ..iv 1 Scope .1 2 Normative references ..1 3 Principle. 4 Reagents 5 Apparatus. ..4 6 Sampling. ..5 :7 Procedure ..5 7.1 Testportion .5 7.2 Determination .5 7.2.1 Preparation of the test solution 5 7.2.2 First nickel precipitation. .5 7.2.3 Second nickel precipitation 6 7.2.4 Gravimetric determination ..7 7.2.5 Titrimetric determination 7 8 Expression of results .8 8.1 Methods of calculation 8.1.1 Gravimetric determination ..8 8.1.2 Titrimetric determination ..8 8.2 Precision. ..8 9 Test report .9 Annex A (informative) Additional information on the international interlaboratory test. ..10 Annex B (informative) Graphical representation of precision data ..11 Annex C (normative) Determination of nickel in combined filtrates by atomic absorption spectrometry ..13 Bibliography ..16 iii icensee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 ithout license from IHS