1、BRITISH STANDARD BS ISO 5954:2007 Cold-reduced carbon steel sheet according to hardness requirements ICS 77.140.50 BS ISO 5954:2007 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 December 2007 BSI 2007 ISBN 978 0 580 56311 9 National fore
2、word This British Standard is the UK implementation of ISO 5954:2007. The UK participation in its preparation was entrusted to Technical Committee ISE/10, Flat rolled steels products. A list of organizations represented on this committee can be obtained on request to its secretary. This publication
3、does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. Amendments issued since publication Amd. No. Date Comments Reference number ISO 5954:2007(E)INT
4、ERNATIONAL STANDARD ISO 5954 Third edition 2007-12-01 Cold-reduced carbon steel sheet according to hardness requirements Tles en acier au carbone lamines froid caractristiques spciales de duret BS ISO 5954:2007ii iii Foreword ISO (the International Organization for Standardization) is a worldwide fe
5、deration of national standards bodies (ISO member bodies). 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 com
6、mittee. International organizations, governmental and 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 accord
7、ance with the rules given in the ISO/IEC Directives, Part 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 require
8、s approval by at least 75 % of the member bodies casting 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 5954 was prepared by Technical C
9、ommittee ISO/TC 17, Steel, Subcommittee SC 12, Continuous mill flat rolled products. This third edition cancels and replaces the second edition (ISO 5954:1998), which has been technically revised. BS ISO 5954:2007 blank1 Cold-reduced carbon steel sheet according to hardness requirements 1 Scope 1.1
10、This International Standard applies to cold-reduced carbon steel sheet and corresponding hardness requirements. It is suitable for applications where the surface is of prime importance. 1.2 The fabrication limits of cold-reduced carbon steel sheet according to hardness requirements are dependent on
11、the specific range of hardness specified or agreed to. It is produced in thicknesses of 0,36 mm and above (commonly produced up to 3 mm) and in widths of 600 mm and over in coils and cut lengths. The hardness is commonly reported as Rockwell B (HRB). 1.3 The following are common hardness ranges (see
12、 5.6): CRH-50 Rockwell B 50 to 70; CRH-60 Rockwell B 60 to 80; CRH-70 Rockwell B 70 to 90; CRH-NN Any Rockwell B range of 20 points up to and including HRB 90 maximum (designated minimum of specified range will be shown). NOTE By agreement between the supplier and purchaser, Rockwell ranges less tha
13、n 20 points can be specified. 1.4 Cold-reduced sheet less than 600 mm wide can be slit from wide sheet and will be considered as sheet. 1.5 This International Standard does not cover commercial quality or drawing qualities (covered in ISO 3574) and cold-reduced carbon steel strip. 2 Normative refere
14、nces The 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 6508 (all parts), Metallic materials Roc
15、kwell hardness test ISO 16162, Continuously cold-rolled steel sheet products Dimensional and shape tolerances BS ISO 5954:20072 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 cold-reduced steel sheet product obtained from hot-rolled descaled
16、 steel sheet by cold-reducing to the required sheet thickness followed by annealing to recrystallize the grain structure NOTE The product is normally supplied in the skin-passed condition. 3.2 skin pass light cold rolling of the product NOTE 1 The purpose of the skin passing is one or more of the fo
17、llowing: a) to minimize the appearance of coil breaks, stretcher strains and fluting; b) to control the shape; c) to obtain the required surface finish. NOTE 2 Some increase in hardness and some loss in ductility will result from skin passing. Cold-reduced sheet supplied in the skin-passed condition
18、 tends to strain-age and this may lead to an increase in the hardness value. Because of this, the hardness values at the time of shipment will be the determining factor as to whether the hardness requirement has been met. 4 Surface characteristics 4.1 General The surface characteristics consist of t
19、he surface quality and the surface finish. The surface quality and surface finish shall be as specified by the purchaser at the time of the order, in accordance with 4.2 and 4.3. For non-skin-passed products, surface quality B (exposed) is not applicable and no requirement for a particular surface f
20、inish can be made. 4.2 Surface quality The products are supplied with either of the surface qualities A or B. 4.2.1 Surface quality A (unexposed) Imperfections, such as pores, slight imperfections, small marks, minor scratches and slight colouring which do not affect the formability or the applicati
21、on of surface coatings, are permitted. 4.2.2 Surface quality B (exposed) The better of the two surfaces shall be free of imperfections which might affect the uniform appearance of quality paint or an electrolytic coating (see 4.4). The other surface shall at least conform to surface quality A. In th
22、e case of delivery of coil and slit coil, the percentage of defects may be greater than in the case of delivery in sheet or cut lengths. This should be taken into account by the purchaser, and the percentage of admissible surface defects may be agreed at the time of the enquiry and order. Unless oth
23、erwise agreed, a single surface of the product shall comply with the specified requirements. The other surface shall be such that, during subsequent treatment, it does not have a deleterious effect on the better surface. BS ISO 5954:20073 4.3 Surface finish When cold-reduced steel sheet is deformed
24、during fabrication, localized areas may roughen to some degree, and such affected portions of the part may require hand-finishing to prepare the surface for the intended application. By agreement at the time of the enquiry and order, ranges for surface roughness may be specified for specific end use
25、s. 4.4 Suitability for surface coating The products may be required for metallic coating by the hot dip coating or electrolytic coating process, or organic coating or other coating. When such a coating is intended, it shall be specified at the time of ordering. 4.5 Oiling As a deterrent to rusting,
26、a coating of oil is usually applied to the product. The oil is not intended as a drawing or forming lubricant and shall be easily removed using degreasing chemicals. The product may be ordered unoiled, if required, in which case, the supplier has limited responsibility if oxidation occurs. 5 Conditi
27、ons of manufacture 5.1 Steelmaking The processes used in marking the steel and in manufacturing cold-reduced sheet according to hardness requirements are left to the discretion of the manufacturer. On request, the purchaser shall be informed of the steelmaking process being used. 5.2 Chemical compos
28、ition The chemical composition (heat analysis) shall not exceed the values given in Tables 1 and 2. NOTE The hardness requirements are normally obtained by controlling carbon, phosphorus, or a combination of carbon and phosphorous. Table 1 Chemical composition (heat analysis), % Mass fraction in per
29、cent Designation C max. Mn max. P max. S max. CRH 50 0,15 0,60 0,15 0,03 CRH 60 0,25 0,60 0,15 0,03 CRH 70 0,25 0,60 0,15 0,03 CRH NN 0,25 0,60 0,15 0,03 BS ISO 5954:20074 Table 2 Limits on additional chemical elements Mass fraction in percent Elements Heat analysis max. Product analysis max. Cua0,2
30、0 0,23 Nia0,20 0,23 Cra, b0,15 0,19 Moa, b0,06 0,07 Nbc0,008 0,018 Vc0,008 0,018 Tic0,008 0,018 aThe sum of copper, nickel, chromium, and molybdenum shall not exceed 0,50 % on heat analysis. When one or more of these elements are specified, the sum does not apply; in which case, only the individual
31、limits on the remaining elements will apply. bThe sum of chromium and molybdenum shall not exceed 0,16 % on heat analysis. When one or more of these elements are specified, the sum does not apply; in which case, only the individual limits on the remaining elements will apply. cAnalysis greater than
32、0,008 % may be supplied after agreement between thre producer and consumer. 5.3 Chemical analysis 5.3.1 Heat analysis An analysis of each heat of steel shall be made by the manufacturer in order to determine compliance with the requirements given in Tables 1 and 2. On request, at the time of orderin
33、g, this analysis shall be reported to the purchaser or his representative. Each of the elements listed in Table 1 shall be included in the report of the heat analysis. If one or more of the elements in Table 2 is/are specified, the analysis shall be reported. 5.3.2 Product analysis A product analysi
34、s may be made by the purchaser to verify the specified analysis of the product and shall take into consideration any normal heterogeneity. Non-killed steels (such as rimmed or capped) are not technologically suited to product analysis. For killed steels, the sampling method and deviation limits shal
35、l be agreed upon between the interested parties at the time of ordering. The product analysis tolerances shall be in accordance with Table 3. Table 3 Product analysis tolerances Element Maximum of specified element % Tolerance over maximum specified % Carbon u 0,15 0,15 to u 0,40 0,03 0,04 Manganese
36、 u 0,60 0,03 Phosphorus u 0,15 0,01 Sulfur u 0,04 0,01 NOTE The above maximum tolerance is the allowable excess over the specified requirements and not the heat analysis. BS ISO 5954:20075 5.4 Weldability This product is normally suitable for welding if appropriate welding conditions are selected. T
37、he hardness may be changed in the heat-affected zone of the welds. When the mass fraction of carbon exceeds 0,15 % or the mass fraction of phosphorus exceeds 0,05 %, welding becomes more difficult. 5.5 Application It is desirable that cold-reduced steel sheet and corresponding hardness requirements
38、be identified for fabrication by the name of the part or by the intended application. Proper identification of the part may include visual examination, prints or description, or a combination of these. Details of fabrication and special requirements (exposed or unexposed, freedom from stretcher stra
39、ins or fluting) shall be specified, as well as the hardness range. 5.6 Hardness ranges The Rockwell hardness ranges represent the values as-shipped. Table 4 Hardness ranges Hardness ranges Designation HRBaHR30TbCRH-50 50/70 50/62,5 CRH-60 60/80 56,5/70 CRH-70 70/90 62,5/77 CRH-NN As agreed on by the
40、 manufacturer and purchaser aFor product thickness W 1 mm. bFor product thickness 1 mm. 6 Dimensional tolerances Dimensional tolerances applicable to cold-reduced carbon steel sheet according to hardness requirements shall be as given in ISO 16162. If flatness tolerances are required, they shall be
41、negotiated. 7 Sampling One representative sample for the hardness test required in Table 4 shall be taken from each lot of sheet for shipment. A lot consists of 50 t or less of sheet of the same designation rolled to the same thickness and condition. 8 Tests The hardness test shall be carried out in
42、 accordance with ISO 6508 on test pieces taken midway between the centre and the edge of the sheet as rolled. 9 Cold bending properties Although bend tests are not required, CRH-50 is expected to be capable of being bent flat on itself through 180, both parallel and perpendicular to the rolling dire
43、ction. CRH-60 is expected to be capable of being bent through 90, with the axis of bend parallel to the rolling direction on a 1 thickness radius, or flat on itself BS ISO 5954:20076 perpendicular to the rolling direction with a 1 thickness radius. CRH-70 is expected to be capable of being bent 90 w
44、ith a 1 thickness radius perpendicular to the rolling direction. By agreement between the supplier and purchaser, a bend test may be carried out with these or other values of bend radii. 10 Retests 10.1 Flaws If any piece shows defective areas, it shall be discarded and another piece substituted. 10
45、.2 Additional tests If a test does not give the specified results, two more tests shall be carried out at random on the same lot. Both retests shall conform to the requirements of this International Standard; otherwise the lot may be rejected. 11 Resubmission The manufacturer may resubmit for accept
46、ance the products that have been rejected during earlier inspection due to unsatisfactory properties, after the manufacturer has subjected them to a suitable treatment (for example, selection or heat treatment). In this case, the tests shall be carried out as if they applied to a new lot. The manufa
47、cturer has the right to present the rejected products to a new examination for compliance with the requirements for another designation. 12 Workmanship The surface condition should be that normally obtained in a cold-reduced product. The steel sheet in cut lengths shall be free from any laminations,
48、 surface flaws and other imperfections that are detrimental to the final product or to subsequent processing. NOTE Processing for shipment in coils does not afford the manufacturer the opportunity of readily observing or removing defective portions, as would be the case on the cut-length product. 13
49、 Inspection and acceptance While not usually required for products covered by this International Standard, when the purchaser specifies that inspection and tests for acceptance shall be observed prior to shipment from the manufacturers works, the manufacturer shall afford the purchasers inspector all reasonable facilities to determine that the steel is being furnished in accordance with this International Standard. Steel that is reported to
