GB/T 13304.1-2008[Including 2017XG] Steels classification -- Part 1: Classification of according to chemical composition (English PDF)

Foreword

GB/T 13304 "Steel Classification" is divided into 2 parts.

- Part 1. Classification of according to Chemical Composition;

- Part 2. Classification of according to Main Quality Classes and Main Property or

Application Characteristics.

This Part is Part 1 of "Steel Classification" (GB/T 13304).

This Part modifies and adopts ISO 4948-1.1982 "Steel - Classification - Part 1.

Classification of Steels into Unalloyed and Alloy Steels Based on Chemical

Composition".

Compared with ISO 4948-1.1982, the main changes in this Part are as follows.

- Basic principles for low alloy steel and its classification were added according to

the actual situations in China;

- Editorial changes were made for Chapter 3; and requirements for significant

digits were added;

- The limit for content of element (like B, Cu, Mn, Mo, Nb, V and La) specified for

unalloyed steel was modified;

- The limit for content of element (like B, Cu, Mn, Mo, Ni, Si, Ti, V and Zr) specified

for alloy steel was modified.

- Table 1 was changed to Table A.1 in Appendix.

Those technical differences have already been marked with vertical single-line on

the margin of relevant clauses for the convenience of comparison.

This Part replaces Part 1 of GB/T 13304-1991 "Steel Classification".

Compared with Part 1 of GB/T 13304-1991, the main changes in this standard are as

follows.

- Editorial changes were made for Chapter 3 (see Chapter 3);

- Example description was added to the original Article 3.1.2.1 (Article 3.1.2.1 in

1991 edition; and Article 3.2.2 in this edition);

- "Unless otherwise negotiated for the contract or order, the limits specified in the

table for the elements of Bi, Pb, Se, Te and La series and other specified

elements (except S, P, C and N) shall not be considered for custom tariff

Steels Classification - Part 1. Classification of according to

Chemical Composition

1 Scope

This Part specifies a basic classification principles of steels into unalloyed, low alloy

and alloy steels based on chemical composition as well as the basic limit for the

element content in above steels.

This Part is applicable to the classification of steels according to chemical

composition.

2 Term and Definition

For the purpose of this Part, the following term and definition apply.

3 Classification

The classification of steels according to chemical composition is as follow.

a) unalloyed steels;

b) low alloy steel;

c) alloy steels.