1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 15208:2012Continuous hot-dip zinc-coatedtwin-roll cast steel sheet ofcommercial qualityBS ISO 15208:2012 BRITISH STANDARDNational forewordThis British Standard is the UK i
2、mplementation of ISO 15208:2012.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/109, Coated and Uncoated Flat Products to be Usedfor Cold Forming.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not
3、 purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 72829 7ICS 77.140.50Compliance with a British Standard cannot confer immunity fromlegal obliga
4、tions.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 April 2012.Amendments issued since publicationDate Text affectedBS ISO 15208:2012 ISO 2012Continuous hot-dip zinc-coated twin-roll cast steel sheet of commercial qualityTles coules entre
5、 cylindres et galvanises en continu par immersion chaud, en acier de qualit commercialeINTERNATIONAL STANDARDISO15208First edition2012-03-15Reference numberISO 15208:2012(E)BS ISO 15208:2012ISO 15208:2012(E)ii ISO 2012 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2012All rights reserved. Unle
6、ss 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 either ISO at the address below or ISOs member body in the country of the requester.ISO co
7、pyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 15208:2012ISO 15208:2012(E) ISO 2012 All rights reserved iiiContents PageForeword iv1 Scope 12 Normative references . 13 Terms and definition
8、s . 14 Thickness 25 Conditions of manufacture . 25.1 Chemical composition . 25.2 Mechanical properties 35.3 Coating . 35.4 Weldability . 45.5 Painting 45.6 Surface treatment 55.7 Coated coil joining 55.8 Dimensional and shape tolerances 56 Sampling 56.1 Chemical composition . 56.2 Tensile test 56.3
9、Coating tests . 56.4 Retest 67 Test methods 67.1 Tensile test 67.2 Coating properties 68 Designation system 68.1 Coating type 78.2 Coating mass 78.3 Coating finish type 78.4 Surface treatment 78.5 Example of designation . 79 Resubmission . 810 Workmanship 810.1 Inspection and acceptance . 811 Markin
10、g . 812 Information to be supplied by the purchaser 9Annex A (normative) Orders requiring base-metal thickness 10Bibliography . 11BS ISO 15208:2012ISO 15208:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodi
11、es). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and
12、non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Pa
13、rt 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting
14、 a vote.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 15208 was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 12, Continuous
15、 mill flat rolled products.iv ISO 2012 All rights reservedBS ISO 15208:2012INTERNATIONAL STANDARD ISO 15208:2012(E)Continuous hot-dip zinc-coated twin-roll cast steel sheet of commercial quality1 ScopeThis International Standard specifies the characteristics of continuous hot-dip zinc-coated twin-ro
16、ll cast steel sheet of commercial quality manufactured using the twin-roll cast steel-making process.The product is intended for applications where resistance to corrosion is of prime importance.The steel sheet is produced in a number of coating mass, surface treatments and ordering conditions.2 Nor
17、mative referencesThe following referenced documents are indispensable for the application of this document. For dated references only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 1460, Metallic coatings Hot di
18、p galvanized coatings on ferrous materials Gravimetric determination of the mass per unit areaISO 2178, Non-magnetic coatings on magnetic substrates Measurement of coating thickness Magnetic methodISO 3497, Metallic coatings Measurement of coating thickness X-ray spectrometric methodsISO 6892-1, Met
19、allic materials Tensile testing Part 1: Method of test at room temperatureISO 7438, Metallic materials Bend testISO 16160, Hot-rolled steel sheet products Dimensional and shape tolerancesISO 16162, Cold-rolled steel sheet products Dimensional and shape tolerancesISO 16163, Continuously hot-dipped co
20、ated steel sheet products Dimensional and shape tolerances3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply3.1continuous hot-dip zinc-coated steel sheetproduct obtained by hot-dip coating of cold-reduced sheet coils or hot-rolled sheet coils on a con
21、tinuous zinc-coating line3.2normal spanglecoating formed as a result of unrestricted growth of zinc or zinc iron crystals during normal solidificationNOTE Normal spangle has a metallic lustre and is the type normally furnished for a wide variety of applications. It may be furnished as coating condit
22、ions S or N (see 8.4); however, it may be variable in appearance and is not suitable for decorative painting.3.3minimized spangle coatingfinish obtained by restricting normal spangle formation during the solidification of the zinc crystalsNOTE This product may have some lack of uniformity in surface
23、 appearance within a coil or from coil to coil. ISO 2012 All rights reserved 1BS ISO 15208:2012ISO 15208:2012(E)3.4smooth finishsurface produced by skin-passing the coated material in order to achieve an improved smooth surface condition as compared with the normal as-coated product3.5differential c
24、oatinglayer having a specified coating-mass designation on one surface and a different coating-mass designation on the other surface3.6skin passlight cold rolling of the zinc-coated steel sheetNOTE The purpose of the skin pass is to produce a higher degree of surface smoothness and, thereby, improve
25、 the surface appearance. The skin pass also temporarily minimizes the occurrence of a surface condition known as stretcher strain (Luders Lines) or fluting during the fabrication of finished parts. The skin pass also controls and improves flatness. Some increase in hardness and loss of ductility can
26、 result from skin passing.3.7twin-roll cast steel sheetsteel sheet produced by casting to near final thickness directly from the liquid metal with minimal hot rolling to achieve the final thickness4 Thickness4.1 Zinc-coated commercial quality twin-roll cast sheet is produced in thicknesses up to 2,0
27、 mm, inclusive, after zinc coating, and in widths up to 2 000 mm in coils and cut lengths.4.2 Zinc-coated twin-roll cast sheets less than 600 mm wide may be slit from wide sheets and may be considered sheets.4.3 The thickness of zinc-coated twin-roll cast sheet steel may be specified as a combinatio
28、n of the base metal and metallic coating or base metal alone. The purchaser shall indicate on the order which method of specifying thickness is required. In the event that the purchaser does not indicate any preference, the thickness as a combination of the base metal and coating shall be provided.
29、Annex A describes the requirements for specifying the thickness as base metal alone.5 Conditions of manufacture5.1 Chemical compositionThe chemical composition (heat analysis) shall not exceed the values given in Tables 1 and 2. On request, a report of the heat analysis shall be made to the purchase
30、r.A verification analysis (product analysis) may be made by the purchaser to verify the specified analysis of the semi-finished or finished steel, and shall take into consideration any normal heterogeneity. Non-killed steels, such as rimmed or capped are not technologically suited for verification a
31、nalysis. The product analysis tolerances are shown in Table 3.The processes used in making the steel and in manufacturing zinc-coated sheets of structural quality are left to the discretion of the manufacturer. Upon request, the purchaser shall be informed of the steel-making process being used.2 IS
32、O 2012 All rights reservedBS ISO 15208:2012ISO 15208:2012(E)Table 1 Chemical composition Heat analysisMass fractions in per cent maximumDesignation Quality C Mn P S SiHRA Commercial 0,15 0,70 0,045 0,035 NOTE In this table, “” indicates that there is no requirement, but the analysis shall be reporte
33、d.Table 2 Limits on additional chemical elementsMass fractions in per cent maximumElement Cu Ni Cr Mo Nb V TiHeat analysis 0,50 0,30 0,30 0,15 0,008 0,008 0,008Product analysis 0,53 0,33 0,34 0,16 0,018 0,018 0,018NOTE Each of these elements listed in this table shall be included in the report of th
34、e heat analysis. Where the amount of copper, nickel, chromium or molybdenum present is less than 0,02 %, the analysis shall be reported as 0,02 %.Table 3 Product analysis tolerancesElementMaximum of specified element%Tolerance over the maximum specified%Carbon 0,15 0,03Manganese 0,70 0,05Phosphorus
35、0,045 0,01Sulfur 0,035 0,01NOTE The maximum tolerance in this table is the allowable excess over the specified requirement and not the heat.5.2 Mechanical propertiesCommercial quality zinc-coated twin-roll cast sheet steels do not have any specified minimum mechanical properties; however, the minimu
36、m tensile strength for commercial quality is normally expected to be 270 MPa. Where the minimum tensile strength is required, the value of 270 MPa may be specified. All tensile strength values are determined to the nearest 10 MPa.5.3 Coating5.3.1 Coating massThe coating mass shall conform to the lim
37、its for the coating designations shown in Table 4. The coating mass is the total amount of zinc on both surfaces of the sheet, expressed in grams per square metre (g/m2) of sheet. The coating mass of differentially coated material shall be agreed upon between the interested parties. If a maximum coa
38、ting mass is required, the manufacturer shall be notified at the time of ordering. ISO 2012 All rights reserved 3BS ISO 15208:2012ISO 15208:2012(E)Table 4 Mass of coating Total both sidesa Minimum check limitCoatingDesignationTriple-spot testg/m2(of sheet)Single-spot testg/m2 (of sheet)Z001 no minim
39、umano minimumaZ100 100 85Z180 180 150Z200 200 170Z275 275 235Z350 350 300Z450 450 385Z600 600 510Z700 700 585NOTE 1 Because of the many variables and changing conditions that are characteristic of continuous zinc coating, the coating mass is not always evenly divided between the two surfaces of a zi
40、nc-coated sheet; neither is the coating evenly distributed from edge to edge. However, it can normally be expected that not less than 40 % of the single-spot check limit will be found on either surface.NOTE 2 The coating thickness can be estimated from the coating mass using the following relationsh
41、ip:100 g/m2total both sides = 0,014 mm total both sides.aNo minimum means that there is no established minimum check limits for triple- and single-spot tests.5.3.2 Coating adherenceThe zinc-coated twin-roll cast sheet shall be capable of being bent in any direction, in accordance with the mandrel di
42、ameter requirements for the coating designations included in Table 5, without flaking of the coating on the outside of the bend. Flaking of the coating within 7 mm from the edge of the test piece shall not be cause for rejection.Table 5 Coating adherence Bend test mandrel diameterCoating designation
43、Quality e 2 mmCommercialUp toZ275Z300Z350Z450Z600Z7001a 1a 2a 2ae = thickness of steel sheet, in millimetre(s)a = bend mandrel diameter = e5.4 WeldabilityThis product is normally suitable for welding if appropriate welding conditions are selected with special attention to the heavier coatings.5.5 Pa
44、intingHot-dip zinc-coated steel sheet is a suitable base for paint, but the first treatment may be different from those used on mild steel. Pretreatment primers, chemical conversion coatings (chromate, phosphate or oxide type) and some paints specially formulated for direct application to zinc surfa
45、ces are all appropriate first treatments for hot-dip zinc-coated sheet. In drawing up a painting schedule, consideration shall be given to whether the hot-dip zinc-coated sheet shall be ordered passivated or not passivated.4 ISO 2012 All rights reservedBS ISO 15208:2012ISO 15208:2012(E)5.6 Surface t
46、reatment5.6.1 Mill passivationA chemical treatment is normally applied to zinc coatings to minimize the hazard of wet storage stain (white rust) during shipment and storage. However, the inhibiting characteristics of the treatment are limited and if a shipment is received wet, the material shall be
47、used immediately or dried.5.6.2 Mill phosphatingZinc-coated steel sheet may be processed chemically at the manufacturers works to prepare all types of coatings for painting without further treatment, except normal cleaning.5.6.3 OilingThe zinc-coated steel sheet as produced may be oiled to prevent m
48、arring and scratching of the soft surface during handling or shipping and to minimize wet storage stain. If the zinc-coated sheet receives a passivating treatment, oiling further minimizes the hazard of wet storage stain.5.7 Coated coil joiningContinuous coil coating lines use various methods to joi
49、n coil ends. These methods include lap welding, butt welding and stitching. The shipment of coils containing the joined ends shall be permitted, if agreed upon between the manufacturer and the purchaser.5.8 Dimensional and shape tolerances5.8.1 Dimensional tolerances applicable to zinc-coated steel sheet shall be as given in ISO 16163. The tolerances for thickness apply to products whose thickness is a combination of base-metal and coating thickness.5.8.2 Where the base metal thickness is specified, th
