As part of our top tips series, we will be undertaking a Q&A with Paul Flynn – an experienced Supervisor at John Tracey Specialist Welding, each month, focusing on the range of exotic metals the team work with. This week, it is aluminium.
- Three top tips when welding Aluminium are…
TIG welding is always preferred.
Distortion is a major issue.
Keep it clean.
2. What equipment is required?
Aluminium can be welded using most of the common welding processes but we will stick with TIG for the purpose of this piece and a must is a welding plant capable of running on Alternating current (AC).
3. What preparation is key?
Probably the most important preparation would be cleaning of grease, oil or water from the welded joint and the removal of the oxidised layer from the surface of the Aluminium this can be achieved using stainless steel wire brush or acetone. Additional heat can help with oxidised layer removal but be careful to follow procedure and also restrain because heat increases distortion. A weld plan is always good prep before welding is carried out on aluminium.
4. Key challenges…. And how to overcome them…
The most common issues would be contamination and distortion with the former causing porous and weak welds and the latter at best being an annoyance and at worst destroying the work piece entirely. These problems can be avoided when welding Aluminium with a few easily achievable prevention measures such as strong backs, jigs, restraints, weld plans, joint design, welding passes and even tungsten size can help prevent distortion. With contamination it’s simply just keep it clean and dry using acetone and stainless wire brush.
5. Safety considerations
As with any welding the major concern is always with fumes and materials inhaled into the lungs so air fed helmets and extraction are a must but one thing about Aluminium that sets it aside from most other materials with regards to safety is the lack of discolouration from welding which is a major cause for burns.