GB/T 3077-2015 Alloy Structure Steels National Standard Full Text
Header
GB/T 3077-2015 Alloy Structure Steels
National Standard of the People's Republic of China | Replaces GB/T 3077-1999
Main Content
Basic Info
Basic Information
- ICS: 77.140.60 H40
- Issue date: 2015-12-10
- Implementation date: 2016-11-01
- Issued by: General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of the People's Republic of China
3 Classification and designation
3 Classification and Designation
3.1 Classification by Metallurgical Quality
- a) Quality steels
- b) Advanced quality steels (suffix "A")
- c) Extra-high quality steels (suffix "E")
3.2 Classification by Processing & Use
- a) Used for pressure process (UP)
- 1) Hot pressure process (UHP)
- 2) Upsetting process (UF)
- 3) Cold drawing (UCD)
- b) Used for cutting process (UC)
3.3 Classification by Surface Condition
- a) Surface by pressure process (SPP)
- b) Surface by acid pickling (SA)
- c) Surface by shot blasting (SS)
- d) Surface by peeling (SF)
- e) Surface by grinding (SP)
4 Ordering Information
4 Ordering Information
The contract or purchase order shall include:
- a) Standard number
- b) Product form designation
- c) Steel grade or ISC code
- d) Controlled residual elements (if required)
- e) Delivery mass/quantity
- f) Dimensions, shape and tolerances
- g) Intended processing and use (UC by default)
- h) Heat treatment or special surface condition (if required)
- i) Hot upsetting test (if required)
- j) Decarburization (if required)
- k) Other special requirements (if required)
5 Dimensions, Shape, Mass and Tolerances
5 Dimensions, Shape, Mass and Tolerances
- 5.1 Hot-rolled round/square bars: GB/T 702
- 5.2 Hot forged round/square bars: GB/T 908
- 5.3 Other cross sections: Applicable standards or mutual agreement
6 Technical Requirements
6 Technical Requirements
6.1 Steel Grades and Chemical Composition
Steel grades, ISC and chemical composition (heat analysis) comply with Table 1.
S, P and residual elements comply with Table 2.
Deviations between heat analysis and product analysis: GB/T 222.
Table 2 – P, S and Residual Elements (Max, %)
| Metallurgical Quality | P | S | Cu | Cr | Ni | Mo |
|---|---|---|---|---|---|---|
| Quality steels | 0.030 | 0.030 | 0.30 | 0.30 | 0.30 | 0.10 |
| Advanced quality steels | 0.020 | 0.020 | 0.25 | 0.30 | 0.30 | 0.10 |
| Extra-high quality steels | 0.020 | 0.010 | 0.25 | 0.30 | 0.30 | 0.10 |
6.2 Melting Method
Determined by manufacturer unless specified in contract.
6.3 Delivery Condition
- 6.3.1 Normally delivered in hot-rolled or hot-forged condition
- 6.3.2 May be delivered heat-treated (annealed, normalized, high-temp tempered) at buyer’s request
- 6.3.3 May be delivered with finished surfaces (ground, peeled) by mutual agreement
6.4 Mechanical Properties
Longitudinal properties comply with Table 3 after specified heat treatment.
Size over Φ80mm allows reduced elongation, reduction of area and impact energy by specified ratios.
Brinell hardness for annealed/high-temp tempered bars complies with Table 3.
6.5 Hot Upsetting
Test piece height reduced to 1/3; no visible cracks. Optional for bars >Φ80mm if guaranteed.
6.6 Macrostructure
No shrinkages, bubbles, cracks, inclusions, flakes, etc. Acceptable severity complies with Table 4.
6.7 Non-metallic Inclusions
Required for advanced/extra-high quality steels; comply with Table 5.
6.8 Grain Size
Extra-high quality steels: Austenite grain size ≥5 grade.
6.9 Decarburization
Total decarburization depth ≤1.5% of nominal diameter for C >0.30% grades.
6.10 Surface Quality
UP bars: No cracks, scabs, laps, inclusions. Defect removal complies with Table 6.
UC bars: Local imperfections allowed within Table 7 limits.
6.11 Special Requirements
By mutual agreement: Composition adjustment, S control, residual element report, UT, hardenability, etc.
7 Test Methods
7 Test Methods
Test items, sampling, location and methods comply with Table 8.
- Chemical composition: GB/T 223, GB/T 4336, etc.
- Tensile test: GB/T 228.1
- Impact test: GB/T 229
- Hardness: GB/T 231.1
- Macrostructure: GB/T 226, GB/T 7736
- Decarburization: GB/T 224
- Inclusions: GB/T 10561
8 Inspection Rules
8 Inspection Rules
- 8.1 Inspection by manufacturer’s quality department; buyer reserves inspection right
- 8.2 Test unit: Same grade, heat, process, dimension, delivery condition
- 8.3 Sampling complies with Table 8
- 8.4 Retest: GB/T 17505
9 Packaging, Marking and Certificate
9 Packaging, Marking and Quality Certificate
Comply with GB/T 2101.
Annex A
Annex A (Informative) Steel Grade Comparison
Equivalent grades in EN 10083-3:2006, ASTM A29/A29M-2012, JIS G 4053-2008.
Keywords Footer
Keywords
GB/T 3077-2015, Alloy Structure Steels, steel grade, chemical composition, mechanical properties, heat treatment, test method, inspection rule, delivery condition, surface quality
Page Navigation
延伸阅读
挑几篇相关的，接着看：