What is Friction Stir Welding?

Friction Stir Welding (FSW) is a solid-state joining process that produces strong, high-integrity welds without melting the material. FSW is used across aerospace, automotive, defence, rail, and energy sectors where traditional welding methods fall short.

A Different Kind of Weld

Unlike conventional welding, FSW doesn’t use high heat to melt metals. Instead, a rotating tool stirs the edges of the material together, using frictional heat and pressure to forge a solid-state bond. The result is a defect-free joint with excellent mechanical properties — especially in hard-to-weld alloys.

How Friction Stir Welding works

A specially designed rotating tool is positioned at the joint between two metal parts.

The tool shoulder presses down, generating frictional heat without melting the material.

The pin stirs and softens the material, mechanically mixing the joint interface.

As the tool moves forward, it forges a solid-phase bond along the seam.

The tool exits, leaving behind a smooth, high-integrity weld with no filler or porosity.

Why Use Friction Stir Welding?

Stronger Joints — Excellent fatigue and tensile properties
Zero porosity — Gas and water-tight joints
No Filler Material Needed — Reduces weight and complexity
Low Distortion — Minimal heat input compared to traditional welding
Weld Dissimilar Materials — Join aluminium to copper, steel, titanium, and more
Environmentally Friendly — No shielding gas, fumes, or sparks and low energy input
Weld any aluminium alloy — Weld all aluminium alloys (including 2xxx and 7xxx series). Weld Plate, cast or extruded aluminium.
Save time and money — Fast welds, with no pre or post-processing, and no consumables

Where is FSW Used?

Applications Across Advanced Industries
Friction Stir Welding is used wherever material performance, safety, and precision are critical. StirLight supports FSW projects in:

Find out more about the sectors we work with

Aerospace — Fuel tanks, structural panels, and aluminium-lithium alloys

Automotive — Battery trays, crash structures, heat exchangers

Defence — Armour panels, specialist enclosures, structural frames

Rail & Marine — Lightweight panels, extrusion joining, corrosion-resistant components

Thermal & Electronics — Cooling plates, power electronics, high-conductivity assemblies, busbars

Let’s explore what FSW can do for you

Whether you are prototyping, developing a new process, or scaling production, we will help you get there faster with expert Friction Stir Welding support.

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