Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
"Continuously Cold Rolled High Strength Steel Sheet and Strip for Automobile" (GB/T 20564) is composed of 7 parts:
- Part 1: Bake Hardening Steel;
- Part 2: Dual Phase Steel;
- Part 3: High Strength Interstitial Free Steel;
- Part 4: High Strength Low Alloy Steel;
- Part 5: Isotropic Steel;
- Part 6: Transformation Induced Plasticity Steel;
- Part 7: Martensitic Steels.
This Part is Part 6 of GB/T 20564.
Appendix A and Appendix B of this Part are informative.
This Part was proposed by the China Iron and Steel Association.
This Part is under the jurisdiction of the National Technical Committee on Iron and Steel of Standardization Administration of China.
Chief Drafting Organizations of this Part: Baoshan Iron & Steel Co., Ltd., China Metallurgical Information and Standardization Institute, and Shougang Group.
Chief drafting staff of this Part: Li Yuguang, Sun Zhongming, Xu Hongwei, Shi Hongyan, Tu Shulin, Wang Xiaohu, Huang Jinhua, Yu Chengfeng, Tang Mu, Zhu Xiaodong, Wang Li and Xu Qing.
NATIONAL STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
中华人民共和国国家标准
GB/T 20564.6-2010
Continuously Cold Rolled High Strength Steel Sheet and Strip for Automobile—
Part 6: Transformation Induced Plasticity Steel
汽车用高强度冷连轧钢板及钢带
第6部分：相变诱导塑性钢
1 Scope
This Part specifies the terms and definitions, classification and codification, size, shape, weight, technical requirements, inspection and test, packaging, marking and quality certificate, etc. for cold-rolled high strength transformation induced plasticity steel sheets and strips (hereinafter referred to as "steel sheets and strips").
This Part is applicable to steel sheets and strips which are 0.50 mm~2.5 mm in thickness and mainly used for producing the structural and reinforcing parts of automobile.
2 Normative References
The following documents contain provisions which constitute provisions of this Part through reference in this text. For dated reference, subsequent amendments to (excluding the corrections), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For any undated references, the latest edition of the document referred to applies.
GB/T 223.5 Steel and Iron-Determination of Acid-Soluble Silicon and Total Silicon Content-Reduced Molybdosilicate Spectrophotometric Method
GB/T 223.9 Iron Steel and Alloy-Determination of Aluminium Content-Chrom Azurol S Photometric Method
GB/T 223.11 Iron Steel and Alloy-Determination of Chromium Content-Visual Titration or Potentiometric Titration Method
GB/T 223.23 Iron Steel and Alloy-Determination of Nickel Content-The Dimethylglyoxime Spectrophotometric Method
GB/T 223.26 Iron Steel and Alloy-Determination of Molybdenum Content-The Thiocyanate Spectrophotometric Method
GB/T 223.53 Methods for Chemical Analysis of Iron, Steel and Alloy-The Flame Atomic Absorption Spectrophotometric Method for the Determination of Copper Content
GB/T 223.59 Iron Steel and Alloy-Determination of Phosphorus Content-Bismuth Phosphomolybdate Blue Spectrophotometric Method and Antimony Phosphomolybdate Blue Spectrophotometric Method
GB/T 223.60 Methods for Chemical Analysis of Iron, Steel and Alloy-The Perchloric Acid Dehydration Gravimetric Method for the Determination of Silicon Content
GBIT 223.63 Methods for Chemical Analysis of Iron, Steel and Alloy-The Sodium (Potassium) Periodate Photometric Method for the Determination of Manganese Content
GB/T 223.64 Iron Steel and Alloy-Determination of Manganese Content-Flame Atomic Absorption Spectrometric Method
GB/T 223.67 Iron Steel and Alloy-Determination of Sulfur Content-Methylene Blue Spectrophotometric Method
GB/T 223.68 Methods for Chemical Analysis of Iron, Steel and Alloy-the Potassium Iodate Titration Method after Combustion in the Pipe Furnace for the Determination of Sulfur Content
GB/T 223.69 Iron Steel and Alloy-Determination of Carbon Contents-Gas-Volumetric Method after Combustion in the Pipe Furnace
GB/T 223.71 Methods for Chemical Analysis of Iron, Steel and Alloy-The Gravimetric Method after Combustion in the Pipe Furnace for the Determination of Carbon Content
GB/T 223.72 Iron Steel and Alloy-Determination of Sulfur Content-Gravimetric Method
GB/T 228 Metallic Materials-Tensile Testing at Ambient Temperature
GB/T 247 General Rule of Package Mark and Certification for Steel Plates (Sheets) and Strips
GB/T 708 Dimension Shape Weight and Tolerance for Cold-Rolled Steel Plates and Sheets
GB/T 2523 Measuring Method of Surface Roughness and Peak Count for Cold-Rolled Metal Sheet (Strip)
GB/T 2975 Steel and Steel Products-Location and Preparation of Test Pieces for Mechanical Testing
GB/T 4336 Standard Test Method for Spark Discharge Atomic Emission Spectrometric Analysis of Carbon and Low-Alloy Steel (Routine Method)
GB/T 5028 Metallic Materials-Sheet and Strip-Determination of Tensile Strain Hardening Exponent (n-values)
GB/T 8170 Rules of Rounding off for Numerical Values & Expression and Judgment of Limiting Values
GB/T 17505 Steel and Steel Products: General Technical Delivery Requirements
GB/T 20066 Steel and Iron-Sampling and Preparation of Samples for the Determination of Chemical Composition
GB/T 20123 Steel and Iron-Determination of Total Carbon and Sulfur Content Infrared Absorption Method after Combustion in an Induction Furnace (Routine Method)
GB/T 20125 Low-Alloy Steel-Determination of Multi-Element Contents-Inductively Coupled Plasma Atomic Emission Spectrometric Method
GB/T 20126 Unalloyed Steel-Determination of Low Carbon Content-Part 2: Infrared Absorption Method after Combustion in an Induction Furnace (with Preheating)
3 Terms and Definitions
For the purposes of this part, the following terms and definitions apply.
3.1
Transformation induced plasticity steels (TR)
The steel microstructure is ferrite, bainite and retained austenite. During forming, the retained austenite can turn into martensite structure through phase transformation, with fairly high work hardening rate, uniform elongation rate and tensile strength. Compared with dual phase steels of the equivalent tensile strength, it has a higher elongation.
4 Classification and Codification
4.1 The designation of steel sheets and strips is composed of three parts, i.e. the initials "CR” of "Cold Rolled", the specified minimum yield strength /specified minimum tensile strength, and the first two initials "TR" of "Transformation Induced Plasticity ".
Example: CR380/590TR
CR- the initials of "Cold Rolled";
380/590- 380: the specified minimum yield strength; 590: the specified minimum tensile strength (MPa);
TR- the first two initials of "Transformation Induced Plasticity ".
4.2 See Table 1 for the classification of steel sheets and strips by the application and characteristics.
Table 1
Designation Application
CR380/590TR Structural and reinforcing parts
CR400/690TR
CR420/780TR
CR450/980TR
4.3 See Table 2 for the classification of steel sheets and strips by the surface quality.
Table 2
Grade Code
Fairly high grade surface FB
High grade surface FC
4.4 See Table 3 for the classification of steel sheets and strips by the surface structure.
Table 3
Surface structure Code
Pitted D
Glossy B
5 Information Required in Order
Foreword i
1 Scope
2 Normative References
3 Terms and Definitions
4 Classification and Codification
5 Information Required in Order
6 Size, Shape, Weight and Allowable Deviation
7 Technical Requirements
8 Inspection and Test
9 Packaging, Marking and Quality Certificate
10 Numerical Rounding
11 Cross Reference between Domestic and Foreign Designations
Appendix A (Informative) Chemical Composition References
Appendix B (Informative) Cross Reference between Domestic and Foreign Designations
