Many industries rely on strong and durable metal components for their machines, systems and end products. To achieve various shapes and sizes, metals and metal alloys in thin sheets or slightly thicker plates are welded together.
One of the most widely used joining processes is arc welding, in which an electric arc melts the metals at their joint.
Friction stir welding (FSW) is a comparatively new technique. It uses a rotating pin tool that generates frictional heat combined with high forging pressure to soften, stir and form a uniform joint between two pieces of metal that remain in solid phase.
The technique has been particularly useful when joining difficult-to-weld materials such as aluminium, and effectively produces lightweight, strong, reliable and recyclable products. It is also safer and more environmentally friendly that conventional arc welding.
In fact, the technique has become the National Aeronautics and Space Administration’s (NASA) method of choice for manufacture of aerospace components including those on the Space Shuttle.