ISO INTERNATIONAL STANDARD 4950-3 Second edition 1995-08-15 High yield strength flat steel products - Part 3: Products supplied in the heat-treated (quenched + tempered) condition Produitsplatsenacierahaute limited'élasticite Part 3: Produits livrés a I'état traite (trempeé + revenu) ISOI Reference number ISO 4950-2:1995(E) ISO 4950-3:1995(E) Foreword ISO (the International Organization for Standardization) is a worldwide federationof nationalstandardsbodies(lsOmemberbodies).Theworkof preparing International_ Standards is normally carried out through isO technical committees. Each member body interested in a subject for which be and non-governmental, in liaison with IsO, also take part in the work. IsO collaborates closely with the International Electrotechnical Commission (lEC)onallmattersofelectrotechnicalstandardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Internationa a vote. International Standard iSO 4950-3 was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 3, Steels for structural purposes. This second edition cancels and replaces the first edition (isO 4950-3: 1981),whichhasbeentechnicalyrevised. ISO 4950 consists of the following parts, under the general title High yield strength flat steel products: Part 1: General requirements --- Part 2: Products supplied in the normalized or controlled rolled con- dition Part 3: Products supplied in the heat-treated (quenched + tempered) condition ISO1995 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical. including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case postale 56 . CH-1211 Geneve 20 . Switzerland Printed in Switzerland ii INTERNATIONAL STANDARD ISO ISO 4950-3:1995(E) High yield strength flat steel products - Part 3: Products supplied in the heat-treated (quenched + tempered) condition 1 Scope ISO 9328-4:1991, Steel plates and strip for pressure purposes -Technical deliveryconditions -Part4: This part of 1SO 4950 specifies the chemical com Weldable fine grain steels with high proof stress position and the mechanical properties of high yield supplied in the normalized or quenched and tempered strength flat steel products supplied in the quenched condition. and tempered condition. For the method of manu- facture, acceptance conditions and marking of these products, see 1sO 4950-1. Manufacture It is applicable to hot-rolled plates and wide flats having a width greater than or equal to 600 mm, in the 3.1 Deoxidation process thickness range 3 mm to 70 mm, in steel which, after quenching and tempering, has a minimum specified All steels shall come from fully killed casts with added yield strength of 460 N/mm2 to 690 N/mm2 for elements that are capable of producing a fine grain. thicknesses less than or equal to 50 mm, and 440 N/mm2 to 670 N/mm2 for thicknesses between 3.2 Delivery condition 50 mm and 70 mm. This part of 1sO 4950 does not apply to products The products shall be delivered in the heat-treated covered by other standards, such as plates for condition, i.e. they have undergone a quenching and pressure vessels (see IsO 9328-4). then a tempering treatment. On request, the purchaser shall be informed of the heat treatment applied by the producer; if, in the course of 2 Normative references subsequent manufacture,a heat treatment is to be carried out by the purchaser, he may find out from the The following standards contain provisions which producer the appropriate conditions for this heat through reference in this text, constitute provisions of treatment. this part of ISO 4950. At the time of publication, the editions indicated werevalid.All standards are subject to revision, and parties to agreements based on this 4 General requirements part of IsO 4950 are encourag