GB/T 3246.2-2026 Inspection method for structure of wrought aluminium and aluminium alloy products—Part 2 : Inspection method for macrostructure (English)
GB/T 3246.2-2026 Inspection method for structure of wrought aluminium and aluminium alloy products—Part 2 : Inspection method for macrostructure English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 3246.2-2026
Inspection method for structure of wrought aluminium and aluminium alloy products - Part 2 : Inspection method for macrostructure
变形铝及铝合金制品组织检验方法 第2部分：低倍组织检验方法
Issue date: 2026-03-31 Implementation date: 2026-10-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
Introduction
1 Scope
2 Normative References
3 Terms and Definitions
4 Summary of Method
5 Reagents
6 Test Specimens
7 Test Procedure
8 Expression of Results
9 Test Report
Annex A (Normative) Methods for Grain Size Classification and Grain Dimension Measurement
Annex B (Informative) Typical Macrostructural Images
Annex C (Normative) Classification of Porosity, Calculation of Densification Degree and Classification of Void Grade
Methods for structure inspection of wrought aluminium and aluminium alloy products — Part 2: Macrostructural inspection method
1 Scope
This document describes the method for the macrostructural inspection of aluminium and aluminium alloy products.
This document applies to the macrostructural inspection of aluminium and aluminium alloy ingots (or billets), plates, sheets, foils, tubes, bars, profiles, wires, forgings and their fabricated products. It also applies to the macrostructural inspection of cast aluminium alloy products.
2 Normative References
The following documents are essential for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 6682 Water for analytical laboratory use — Specification and test methods
GB/T 8005 (all parts) Aluminium and aluminium alloys — Terms and definitions
GB/T 8170 Rules of rounding off for numerical values and expression and judgement of limiting values
GB/T 22638.1-2016 Test methods for aluminium foil — Part 1: Determination of thickness
GB/T 26492 (all parts) Defects of wrought aluminium and aluminium alloy ingots and products
GB/T 43139-2023 Determination of density of cast aluminium alloy by pressure solidification sample
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 8005 (all parts), GB/T 26492 (all parts) and the following apply.
3.1 macrostructure
The macrostructural features and defects of a material observed by the unaided eye or at magnifications of 50× or less.
3.2 grain
An individual crystal having the same atomic structure within the microstructure of a polycrystalline material.
NOTE: A grain may contain twins or subgrains.
3.3 grain boundary
A narrow region in the microstructure of a polycrystalline material where the orientation transitions from one grain to another, thereby distinguishing adjacent grains.
3.4 columnar grain
A grain in a cast structure having a columnar morphology.
NOTE: Columnar grains are produced by directional heat flow, and their growth direction is opposite to the direction of heat flow.
3.5 equiaxed grain
A grain having approximately equal axial lengths in all three spatial dimensions.
3.6 recrystallisation
The process by which a plastically worked solid metal or alloy, at an appropriate temperature and time, eliminates work hardening and forms a new grain structure through grain nucleation and growth.
NOTE: Recrystallisation includes partial recrystallisation and complete recrystallisation. Complete recrystallisation refers to the replacement of deformed grains by newly formed, completely strain free grains.
3.7 cast structure
The structure obtained after liquid metal or alloy is poured into a mould (casting mould) and solidifies.
NOTE 1: A typical ingot cast structure usually consists of a surface fine grain zone, a columnar grain zone and a central equiaxed grain zone.
NOTE 2: Cast structures may be present in insufficiently deformed microstructures.
3.8 deformation structure
A structure formed when a cast structure, annealed polycrystalline structure or other polycrystalline structure undergoes irreversible morphological and internal structural changes under the action of external forces during a plastic working process (such as rolling, forging, extrusion, drawing, stamping, etc.), resulting in a structure with specific characteristics.
NOTE: Mainly manifested as grains, impurities and second phases elongated along the direction of deformation.
4 Summary of Method
The grains and defects in the microstructure (cast structure, deformation structure, etc.) of the material are examined and analysed visually or using a magnifying glass. The grain size and defects such as porosity, inclusions, cracks, coarse grain rings, incomplete bonding, press folds, uneven flow lines, segregation layers, grain layer splitting and billet transition zones are evaluated and characterised.
Standard
GB/T 3246.2-2026 Inspection method for structure of wrought aluminium and aluminium alloy products—Part 2 : Inspection method for macrostructure (English Version)
Standard No.
GB/T 3246.2-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
29000 words
Price(USD)
870.0
Implemented on
2026-11-1
Delivery
via email in 1~8 business day
Detail of GB/T 3246.2-2026
Standard No.
GB/T 3246.2-2026
English Name
Inspection method for structure of wrought aluminium and aluminium alloy products—Part 2 : Inspection method for macrostructure
GB/T 3246.2-2026 Inspection method for structure of wrought aluminium and aluminium alloy products—Part 2 : Inspection method for macrostructure English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS
CCS
National Standard of the People's Republic of China
GB/T 3246.2-2026
Inspection method for structure of wrought aluminium and aluminium alloy products - Part 2 : Inspection method for macrostructure
变形铝及铝合金制品组织检验方法 第2部分：低倍组织检验方法
Issue date: 2026-03-31 Implementation date: 2026-10-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
Introduction
1 Scope
2 Normative References
3 Terms and Definitions
4 Summary of Method
5 Reagents
6 Test Specimens
7 Test Procedure
8 Expression of Results
9 Test Report
Annex A (Normative) Methods for Grain Size Classification and Grain Dimension Measurement
Annex B (Informative) Typical Macrostructural Images
Annex C (Normative) Classification of Porosity, Calculation of Densification Degree and Classification of Void Grade
Methods for structure inspection of wrought aluminium and aluminium alloy products — Part 2: Macrostructural inspection method
1 Scope
This document describes the method for the macrostructural inspection of aluminium and aluminium alloy products.
This document applies to the macrostructural inspection of aluminium and aluminium alloy ingots (or billets), plates, sheets, foils, tubes, bars, profiles, wires, forgings and their fabricated products. It also applies to the macrostructural inspection of cast aluminium alloy products.
2 Normative References
The following documents are essential for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 6682 Water for analytical laboratory use — Specification and test methods
GB/T 8005 (all parts) Aluminium and aluminium alloys — Terms and definitions
GB/T 8170 Rules of rounding off for numerical values and expression and judgement of limiting values
GB/T 22638.1-2016 Test methods for aluminium foil — Part 1: Determination of thickness
GB/T 26492 (all parts) Defects of wrought aluminium and aluminium alloy ingots and products
GB/T 43139-2023 Determination of density of cast aluminium alloy by pressure solidification sample
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 8005 (all parts), GB/T 26492 (all parts) and the following apply.
3.1 macrostructure
The macrostructural features and defects of a material observed by the unaided eye or at magnifications of 50× or less.
3.2 grain
An individual crystal having the same atomic structure within the microstructure of a polycrystalline material.
NOTE: A grain may contain twins or subgrains.
3.3 grain boundary
A narrow region in the microstructure of a polycrystalline material where the orientation transitions from one grain to another, thereby distinguishing adjacent grains.
3.4 columnar grain
A grain in a cast structure having a columnar morphology.
NOTE: Columnar grains are produced by directional heat flow, and their growth direction is opposite to the direction of heat flow.
3.5 equiaxed grain
A grain having approximately equal axial lengths in all three spatial dimensions.
3.6 recrystallisation
The process by which a plastically worked solid metal or alloy, at an appropriate temperature and time, eliminates work hardening and forms a new grain structure through grain nucleation and growth.
NOTE: Recrystallisation includes partial recrystallisation and complete recrystallisation. Complete recrystallisation refers to the replacement of deformed grains by newly formed, completely strain free grains.
3.7 cast structure
The structure obtained after liquid metal or alloy is poured into a mould (casting mould) and solidifies.
NOTE 1: A typical ingot cast structure usually consists of a surface fine grain zone, a columnar grain zone and a central equiaxed grain zone.
NOTE 2: Cast structures may be present in insufficiently deformed microstructures.
3.8 deformation structure
A structure formed when a cast structure, annealed polycrystalline structure or other polycrystalline structure undergoes irreversible morphological and internal structural changes under the action of external forces during a plastic working process (such as rolling, forging, extrusion, drawing, stamping, etc.), resulting in a structure with specific characteristics.
NOTE: Mainly manifested as grains, impurities and second phases elongated along the direction of deformation.
4 Summary of Method
The grains and defects in the microstructure (cast structure, deformation structure, etc.) of the material are examined and analysed visually or using a magnifying glass. The grain size and defects such as porosity, inclusions, cracks, coarse grain rings, incomplete bonding, press folds, uneven flow lines, segregation layers, grain layer splitting and billet transition zones are evaluated and characterised.
