4948/1 OSI) International Standard INTERNATIONAL ORGANIZATION FOR STANDARDIZATION·MEKAYHAPOAHAA OPrAHM3ALWA HO CTAHAAPTW3AWWOORGANISATION INTE RNATIONALE DE NORMALISATION Steels - Classification Part 1 : Classification of steels into unalloyed and alloy steels based on chemical composition Aciers - Classification Partie 1: Classification en aciers allies et en aciers non allies basée sur la composition chimique First edition -- 1982-06-15 Ref. No. ISO 4948/1-1982 (E) UDC. 669.14/.15 SO 4948/1-1982 ( Descriptors : steels, unalloyed steels, alloy steels, classifications, chemical composition. Pricebased on 2pages Copyright International Organization for Standardization Not for Resale Foreword nationai standards institutes (Iso member bodies). The work of developing Inter- national Standards is carried out through ISO technical committees. Every member body interested in a subject for which a technical committee has been set up has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the Iso Council. International Standard ISo 4948/1 was developed by Technical Committee ISO/TC 17, Steel, and was circulated to the member bodies in January 1981. It has been approved by the member bodies of the following countries : Australia Iran Poland Austria Iraq Romania Belgium Italy South Africa, Rep. of Bulgaria Spain Japan Canada Korea, Dem. P. Rep. of Sweden China Korea, Rep. of Switzerland France Netherlands Venezuela Hungary New Zealand India Norway The member bodies of the following countries expressed disapproval of the document on technical grounds : Czechoslovakia United Kingdom USA @ International Organization for Standardization, 1982 Printed in Switzerland Copyright International Organization for Standardization Not for Resale ISO 4948/1-1982 (E) INTERNATIONAL STANDARD Steels Classification Part 1 : Classification of steels into unalloyed and alloy steels based on chemical composition Scope and field of application 3.1.1.1 Where a minimum value or range is specified for the ladle analysis of the elements given in the table, the minimum This part of ISO 4948 lays down a classification of steels into value shall be taken for classification. unalloyed and alloy steels based on chemical composition. Part 2 lays down the classification of unalloyed and alloy steels according to main quality classes and main property or applica- 3.1.1.2 Where the manganese content of the ladle analysis is tion characteristics. specified as a maximum value only, this maximum value shall be taken for classification. Definition 2 For the purpose of this International Standard, the following 3.1.1.3 Where for elements other than manganese a max- definition applies : imum value only is specified for the ladle analysis, a value of 0,7 times this maximum value shall be taken for classification. steel : A material with iron as the predominant element, having a carbon content generally less than 2,o % and containing other elements. A limited number of chromium steels may have 3.1.1.4 Where there is no standard or specification or ordered more than 2,0 % carbon, but 2,0 % is the usual dividing line composition, the ladle analysis reported by the manufacturer between steel and cast iron. shall be taken for classification. The results of product analysis may deviate from those of the Classification 3 ladle analysis to an extent permitted by the appropriate product standard. Where the product analysis indicates a value which 3.1 Steels are classified as would place the steel in a class other than that standard, then its inclusion in the class originally intended shall, if necessary, a) unalloyed steels; be separately and reliably substantiated. b) alloy steels. 3.1.2 Unalloyed steels are thos