This standard specifies notations for designations of iron and steel.
This standard is applicable to the preparation of designations for pig iron, carbon structural steels, low-alloy structure steel, quality carbon structural steel, free-cutting steel, alloy structure steel, spring steel, tool steel, bearing steel, stainless steel, heat-resisting steel, steel for welding, cold rolled electric steel, electromagnetic pure iron, pure iron for raw material, high resistance alloys for electrical heating and relevant steels for special use etc..
Notations for designations of iron and steel which are not specified in this standard shall be prepared in accordance with principles specified in this standard.
Notations for designations of powder metallurgical materials, cast iron (piece), cast steel (piece), ferroalloy, superalloys/high temperature intermetallic materials, corrosion-resisting alloy and precision alloy etc. shall respectively conform to provisions specified in the following national standards.
GB/T 4309 "Classification and Designation for Powder Metallurgy Materials"
GB/T 5612 "Code for Representing Cast Iron"
GB/T 5613 "Code for Representing Cast Steels"
GB/T 7738 "Notations for Designation of Ferroalloys"
GB/T 14992 "Classification and Designation for Superalloys and High Temperature Intermetallic Materials"
GB/T 15007 "Designations of Corrosion-resisting Alloy"
GB/T 15018 "Designation of Precision Alloys"
2 Basic Principles
2.1 The designation of any iron or steel listed into the national/professional standards shall be prepared in accordance with the notations for designations specified in this standard.
2.2 Capitalized Chinese phonetic letters, chemical element symbols and Arabic numerals are generally used to indicate the designations of iron and steel. For the convenience of international communication and trade, capitalized English letters or international practices may be adopted as well. Symbols of common chemical elements are detailed in Table 1.
2.3 If the Chinese phonetic alphabet or English letter is used to express the product name, purpose, characteristics and process method, generally the first letter of the phonetic transcription or the English word of the product is adopted. If the first letter is the same with that of another product, the second or third letter shall be adopted; or first letters of two (or more) phonetic transcriptions or English words shall be adopted at the same time.
If Chinese phonetic letters or English letters are adopted, in principle, only one letter is adopted; in general, the number of adopted letters shall not exceed 3.
2.4 The notation for each part of the product designation shall meet the corresponding provisions. Each part shall be arranged in the right sequence and the unnecessary ones may be omitted. Except for special regulations, no gap shall be reserved between letters, symbols and numerals.
2.5 The mass fraction is used to express the element content of the product designation.
Table 1
Contents Foreword I 1 Scope 2 Basic Principles 3 Notations for Designations
1 Scope
This standard specifies notations for designations of iron and steel.
This standard is applicable to the preparation of designations for pig iron, carbon structural steels, low-alloy structure steel, quality carbon structural steel, free-cutting steel, alloy structure steel, spring steel, tool steel, bearing steel, stainless steel, heat-resisting steel, steel for welding, cold rolled electric steel, electromagnetic pure iron, pure iron for raw material, high resistance alloys for electrical heating and relevant steels for special use etc..
Notations for designations of iron and steel which are not specified in this standard shall be prepared in accordance with principles specified in this standard.
Notations for designations of powder metallurgical materials, cast iron (piece), cast steel (piece), ferroalloy, superalloys/high temperature intermetallic materials, corrosion-resisting alloy and precision alloy etc. shall respectively conform to provisions specified in the following national standards.
GB/T 4309 "Classification and Designation for Powder Metallurgy Materials"
GB/T 5612 "Code for Representing Cast Iron"
GB/T 5613 "Code for Representing Cast Steels"
GB/T 7738 "Notations for Designation of Ferroalloys"
GB/T 14992 "Classification and Designation for Superalloys and High Temperature Intermetallic Materials"
GB/T 15007 "Designations of Corrosion-resisting Alloy"
GB/T 15018 "Designation of Precision Alloys"
2 Basic Principles
2.1 The designation of any iron or steel listed into the national/professional standards shall be prepared in accordance with the notations for designations specified in this standard.
2.2 Capitalized Chinese phonetic letters, chemical element symbols and Arabic numerals are generally used to indicate the designations of iron and steel. For the convenience of international communication and trade, capitalized English letters or international practices may be adopted as well. Symbols of common chemical elements are detailed in Table 1.
2.3 If the Chinese phonetic alphabet or English letter is used to express the product name, purpose, characteristics and process method, generally the first letter of the phonetic transcription or the English word of the product is adopted. If the first letter is the same with that of another product, the second or third letter shall be adopted; or first letters of two (or more) phonetic transcriptions or English words shall be adopted at the same time.
If Chinese phonetic letters or English letters are adopted, in principle, only one letter is adopted; in general, the number of adopted letters shall not exceed 3.
2.4 The notation for each part of the product designation shall meet the corresponding provisions. Each part shall be arranged in the right sequence and the unnecessary ones may be omitted. Except for special regulations, no gap shall be reserved between letters, symbols and numerals.
2.5 The mass fraction is used to express the element content of the product designation.
Table 1
Contents of GB/T 221-2008
Contents
Foreword I
1 Scope
2 Basic Principles
3 Notations for Designations
