A solid-state joining technique called friction stir welding creates full contact joints with exceptional integrity. There is no need for external filler materials, flux or shielding gases for friction stir welding. All in-process control and quality control is automated, the process is fully repeatable and machine controlled.
How does it work?
When two workpieces rotate against each other while being compressed by an axial force, heat is produced by friction between the two contact surfaces, which causes the interface material to plasticise. The plasticised material is extruded together with the interface material and any impurities by the compressive forging force, which also promotes molecular bonding and results in a homogeneous connection between the original materials.
Flow of the friction stir welding process.
– Friction contact stage
Rotation is applied to a workpiece. In addition, it is simultaneously subjected to a specific amount of pressure from the opposing component.
– Friction stage
Relative motion (rotation) and simultaneous pressure cause the contact surfaces to heat up.
– Forging stage
The pressure increases again when the rotation stops. Because of this, the plasticised material can be bonded to the other component.
– Waiting stage
Both substances are still under pressure and can gradually cool down afterwards.
Benefits of friction stir welding over traditional welding
– High quality joints are guaranteed by friction stir welding.
– The entire joint contact is joined completely homogeneously by friction stir welding.
– Various metals can be joined by friction welding.
– Friction welding prevents materials from melting.
– Excellent speed connections with high integrity
– Human error is eliminated by automated processes.
– Highly suitable for manufacturing in quantities ranging from single prototypes to large volumes.
– Because no consumables are needed, friction stir welds tend to cost less.
– For this method, pre-weld preparations may not be as important.
You can even weld combinations of foreign materials with the help of KUKA systems, which guarantees you the highest quality in the manufacture of safety-relevant components:
– Brazing of copper and aluminium.
– Welding of stainless steel and copper
– Welding of stainless steel and aluminium
– Welding of carbon and stainless steel
– Welding of aluminium and titanium.
For any information, we are always available to find solutions for your robotic projects. Don’t hesitate to contact us.