Universal Fabrications Aluminium Welding Specialists

When it comes to manufacturing high-quality aluminium products, the importance of choosing a leading specialist like Universal Fabrications cannot be overstated. With decades of experience welding complex aluminium fabrications, Universal is ideally placed to support your projects. Whether you are looking to prototype a new design or scale up your production, get in touch.

The Challenges of Aluminium Welding

Welding aluminium can be challenging, even for experienced welders. Its high thermal conductivity, low melting point, and the rapid formation of an oxide layer pose many welding differences from steel and other materials. Special techniques and precautions are needed for a successful weld. Mistakes can lead to weak joints, defects, or even complete weld failure. To help you achieve consistently high-quality results in aluminium welding, we’ve compiled the top five critical aspects that, we as a leading specialist, focus on.

1. Correct Cleaning Prior to Welding


One of the most common mistakes in aluminium welding is failing to clean the material properly before welding. Aluminium quickly forms an oxide layer when exposed to air, and this layer has a much higher melting point than the aluminium beneath it. If the oxide layer isn’t removed, it can cause contamination in the weld, leading to poor fusion and weak joints.

At Universal our Welders:

  • Always clean the aluminium surface thoroughly before welding. 
  • Use a stainless-steel wire brush dedicated to aluminium to remove the oxide layer. 
  • Degrease the material using a suitable solvent to remove any oils or contaminants that could interfere with the weld.

2. Appropriate Application of Heat

Aluminium’s high thermal conductivity means that it dissipates heat very quickly. This can lead to several issues, such as insufficient penetration, burn-through, or distortion of the material. Many welders, especially those accustomed to working with steel, underestimate the heat management required for aluminium.

At Universal our Welders:

  • Use the most appropriate welding method for the project, this could be methods such as CMT Welding, Laser Welding and TIG welding.
  • Use a higher amperage setting than you would for steel, and consider preheating thicker aluminium sections to ensure consistent penetration. 
  • Adjust travel speed and arc length to maintain control over the heat input.

3. Selecting the Correct Filler Material Selection

Choosing the wrong filler material is another frequent error in aluminium welding. The filler material must be compatible with the base metal to ensure a strong and durable weld. Using the wrong filler can lead to cracking, weak joints, or even complete weld failure.

At Universal our Welders:

  • Select the filler material that matches the aluminium alloy being welded. For example, 4043 and 5356 are common fillers, but the choice depends on the specific aluminium alloy and the intended use of the weld. 
  • Always consult the material specifications and guidelines to ensure compatibility.

4. Paying Close Attention to Oxidation During the Weld

Even during the welding process, aluminium can continue to oxidize, especially if there’s inadequate shielding gas coverage. This oxidation can lead to contamination within the weld, causing defects like porosity, inclusions, or poor fusion.

At Universal our Welders:

  • Ensure adequate shielding gas coverage (typically 100% argon) during the welding process to prevent oxidation. 
  • Maintain a consistent gas flow rate, check for leaks in your equipment, and ensure the torch angle is appropriate to protect the weld pool from exposure to air. (TIG welding, in particular, requires careful attention to shielding.)

5. Correct Welding Technique 

Welding aluminium successfully requires a different technique compared to steel. Mistakes such as an incorrect torch angle, too much or too little travel speed, or improper electrode choice can result in a weak or defective weld.

At Universal our Welders:

  • When TIG welding, maintain a steady, short arc length and use a push technique (rather than pulling) to keep the weld pool stable and the oxide layer out of the way. 
  • When MIG welding, ensure the travel speed is consistent, and use a slight push angle with a clean, steady motion.

Whether you are looking to prototype a new design or scale up your production, get in touch.

Tel: 02476 370 272 or email@universalfabrications.com 

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