welding

Aluminium welding standard AWS D1.2

October 29, 2025
admin

introduction

AWS D1.2 is one of the most important reference standards for welding aluminum and its alloys. Published by the American Welding Society (AWS), this standard contains technical requirements, performance recommendations, and inspection criteria for aluminum welds. This article provides a comprehensive overview of this important standard.

AWS D1.2 Standard View

1. Scope

  • Welding of aluminum alloy

  • Thickness 1/16 inch (1.6 mm) or more

  • Arc welding processes (GTAW, GMAW, SMAW)

2. Published publications

  • First edition: 1969

  • Latest version: AWS D1.2/D1.2M:2021

  • Update every 5-7 years.

AWS D1.2 Standard Structure

1. Main sections

  • Section 1     : General Requirements

  • Part Two     : Design of welded joints

  • Part 3     : Preparation and warm-up

  • Section 4     : Staff Qualifications

  • Section 5     : Welding processes

  • Section 6     : Inspection and Quality Control

2. Important Investments

  • Annex A: Standards for non-destructive testing methods

  • Appendix B: WPS and PQR samples

  • Appendix C: Design Guidelines

Fog separators: a technology for separating droplets from gas streams.AWS D1.2 Design Requirements

1. Types of communication

  • Connection terminals     : for different thicknesses

  • Corner connection     : Structures within the box

  • Contact for protection     : For reinforcement

2. Welded groove constructions

  • V-groove     : for medium thickness

  • U-shaped trough     : for large fish

  • J-Nut     : Used for supplying welding filler material.

3. Special notes on aluminium

  • high thermal expansion

  • high thermal conductivity

  • Surface rust resistance

Materials and textures in AWS D1.2

1. Aluminum alloy assembly

  • Series 1xxx     : Pure aluminum

  • Series 3xxx     : Manganese alloys

  • Series 5xxx     : Magnesium alloys

  • Series 6xxx     : Magnesium-silicon alloys

2. Selection of the welding wire

  • Compatibility with base alloys

  • appropriate degree of purity

  • Standard sizes

3. Shielding gases

  • pure argon

  • a mixture of argon and helium

  • Purity at least 99.99%

Welding processes are discussed.

1. TIG welding (GTAW)

  • Suitable for sensitive fish.

  • Excellent welding quality

  • low speed

2. Metal inert gas (MIG) welding

  • high speed

  • Suitable for mass production.

  • Requires fine-tuning

3. Manual metal arc welding (SMAW)

  • For repair work

  • Electrodes with a special coating

  • High qualifications required

Welding performance requirements

1. Surface preparation

  • dry cleaning

  • Mechanical cleaning with a brush

  • Remove surface rust

2. Preheating

  • Temperature 150-250°F (65-120°C)

  • uniform temperature control

  • Measurement methods

3. Inlet temperature control

  • Inlet temperature limiter

  • Welding sequence

  • controlled cooling

Assessment of employee qualifications

1. Welder qualifications (WQR)

  • Practice tests

  • Valid for 6 months

  • Renewal conditions

2. Operator qualification

  • For automatic welding

  • Functional tests

  • documentation

3. Welding Inspector (CWI)

  • AWS Certification

  • Expertise in aluminium

  • Experience

Quality control and inspection

1. Non-destructive testing

  • Visual inspection (IV)     : Step one

  • Penetration test (PT)     : For surface cracks

  • Ultrasonic testing (UT)     : for the detection of internal defects

  • Radiography (RT)     : for the assessment of volume defects

2. Admission criteria

  • Permissible gap size

  • acceptable porosity

  • Welding standards

3. Documentation

  • Inspection reports

  • Restoration documentation

  • Registration of welding parameters

Comparison of AWS D1.2 with other standards

1. Differences to     AWS D1.1

  • Special considerations for aluminium

  • Various welding processes

  • Special admission criteria

2. Differences to ISO 15614

  • ISO quality system approach

  • Differences in the documents

  • Verification requirements

Industrial application

1. Aerospace industry

  • Aircraft fuselage structure

  • fuel tanks

  • components

2. Shipping industry

  • shipbuilding

  • Marine structures

  • Ship equipment

3. Transportation industry

Key implementation points

1. Thermal management

  •    Avoid distortions  .

  • Adjustment of cooling speed

  • Prevention of thermal cracks

2. Cleaning

  • Before and after welding

  • Use appropriate   solvents.

  • Prevention of environmental pollution

3. Selection of consumables

  • Compatibility with base alloys

  • Storage conditions

  • Expiry date

Changes in the 2021 edition

1. Important Updates

2. Improvements Implemented

  • Clarify design requirements

  • Update of the parameter tables

  • Extended Inspection Guidelines

Diploma

AWS D1.2, the most important standard for aluminum welding, contains comprehensive technical and operational   requirements     . Strict adherence to this standard improves the quality, safety, and durability of aluminum welds. Due to the unique properties of aluminum, meticulous attention to the details of this standard is crucial for achieving the desired results.

Frequently Asked Questions

1. Is AWS D1.2 suitable for welding aluminum with a thickness of less than 1.6 mm?

No, this standard applies to material thicknesses of 1.6 mm and above. For material thicknesses below 1 mm, please refer to the manufacturer’s instructions.

2. What is the main difference between welding aluminium and steel according to AWS D1.2?

The high thermal conductivity, the stability of surface oxidation and the high thermal expansion of aluminium require special procedures, which are explained in this standard.

3. Is preheating necessary for all aluminum alloys?

No, the need for preheating depends on     the alloy type and the workpiece thickness  . Detailed information can be found in AWS D1.2.

4. Which non-destructive testing method is best suited for aluminium?

The best results for aluminium are usually achieved by penetrant testing (LT) for surface cracks and ultrasonic testing (UT) for internal defects.

5. How can I access the latest AWS D1.2 version?

The standard can be purchased or viewed online at the official website of the American Welding Society (www.aws.org).