Friction Stir Welding: a revolution in aluminium welding

Friction Stir Welding of aluminium parts is simple, repeatable, and affordable. However, this technology is still barely known to many. Read on and find out why you should know about it!

The aluminium sector is on the rise, being the fastest growing metal: 6% per year! The use of aluminium extends to a wide variety of sectors. It can be used for window frames as well as automotive heat sinks or aircraft parts. This wide range of uses of aluminium is due to its particular properties: low density, non-toxic, high thermal conductivity, excellent corrosion resistance and the fact that it can be easily formed, machined and cast. Furthermore, it is the sixth most ductile metal and the second most malleable. On top of it, its major asset is its lightness.

Every industry sector involved in transport is interested in aluminium, and looking for the most efficient, as well as economical, methods of working with this material. That’s why, when it comes to aluminium welding, Friction Stir Welding‘s high-performance is acknowledged.

This innovative technology is subject to major developments and is already used in numerous applications: automotive, aeronautics, space, energy or even nuclear. Aluminium is everywhere: it is used for the construction of aeroplane fuselage components (an increasingly widespread application), launchers (rockets), boat covers, many automobile parts such as heat sinks, inverters etc.

FSW technology: advantages for aluminium welding

Economic advantages of Friction Stir Welding for aluminium welding

Significant savings in cycle time and increased reproducibility of assembly operations through process automation.

No material input, no preparation of joints, low energy consumption.

Mass saving by eliminating rivets or limiting the thickness of the assembly.

Multi-material assemblies allow expensive materials to be used only in strategic locations where they have a high added value. Therefore, non-critical parts of a part can be manufactured using less expensive materials.

Reduced welding costs due to fewer consumables (1 tool = welding of 1500-m long).

Post-weld inspection is also reduced.

If we talk specifically about the Stirweld FSW head, we find two great advantages to add: the investment is limited since the welding is carried out on an existing CNC machine and the head is available for renting (starting from 1900 € / month).

Technological advantages of Friction Stir Welding for aluminium welding

Welding of several grades of aluminium together (no hot cracking or porosity), heterogeneous assemblies.

FSW welding presents excellent thermal and electrical conductivity.

Qualification of operating modes (international standards) – welding standard: ISO 25239.

FSW can weld of all aluminium alloys (1xxx, 2xxx, 4xxx, 5xxx, 6xxx, 7xxx) This technology also makes it easy to weld aluminium foundry, including die-casting.

Welding without leakage (neither water, acid nor air).

Multimaterial assemblies allow the characteristics of each of their components (lightness, conductivity, resistance, hardness, etc.) to be exploited to the full.

It is possible to form after welding: stamping or bending the welded parts without risk of cracking.

Welding capacity up to 20 mm.

High mechanical strength of the weld – fatigue strength close to the base material.

No smoke emissions and no consumables (savings in raw materials).

By allowing the manufacture of lighter parts while maintaining their mechanical properties, friction stir welding make it possible to reduce fuel consumption in the automotive, aeronautical and general transport sectors. Consequently, greenhouse gas and pollutant emissions are reduced.