Welding of Aluminium and Its Alloys
1 – Introduction to the welding of aluminium
- Introduction
- Characteristics of aluminium
- Products forms
- Welding: a new definition
2 – Welding metallurgy
- Introduction
- Strengthening mechanisms
- Aluminium weldability problems
- Strength loss due to welding
3 – Material standards, designations and alloys
- Designation criteria
- Alloying elements
- CEN designation system
- Specific alloy metallurgy
- Filler metal selection
4 – Preparation for welding
- Introduction
- Storage and handling
- Plasma-arc cutting
- Laser beam cutting
- Water jet cutting
- Mechanical cutting
- Cleaning and degreasing
Some interesting pictures from this book
Figure 2.1 – Definition of weld features
Figure 2.3 – General relationship of grain size with strength, ductility and toughness
Figure 2.5 – Illustration of the effect of cold work on strength, hardness and ductility
Figure 2.6 – Illustration of the solution treatment and age-(precipitation) hardening heat treatment cycle
Figure 2.11 – Solidification of a metal
Figure 2.17 – Effect of annealing temperature on cold work and strength
Figure 2.18 – Effect of welding on strength in cold worked alloy.
Figure 2.19 – Effect of welding on 6061-T6 age-hardened alloy – as welded.
- The cold worked alloys will experience a loss of strength due to recrystallization in the HAZ. Recrystallization begin to take place when the temperature in the HAZ exceeds 200 ⁰C and progressively increases with full annealing taking place over 300 ⁰C (see Figure 2.17). In Figure 2.18 is shown the loss of strength for a TIG welded 5xxx alloy.
- The loss in tensile strength in the heat-treatable alloys (Figure 2.19) is caused by a dissolution of the precipitates in the 2xxx series aluminium alloys and a coarsening or overageing of the precipitates in the 6xxx and 7xxx aluminium alloys.