What is friction welding?
The friction welding process uses pressure and friction to heat the materials. This limits the thermal stress largely to the area where the workpieces come into contact with each other. This allows workpieces made of different materials, such as steel and aluminum, to be joined together.
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How does friction welding work?
Friction welding is used to join two workpieces. One of the workpieces rotates relative to the other. Both workpieces touch each other during this process, creating friction between them. The friction generates heat, which plasticizes the material at the interface.
The plasticized material is then displaced by the pressure forging force. This also makes it possible to join surfaces that have not been cleaned. Contaminants are simply pressed out during this process. This promotes a homogeneous bond at the molecular level between the two base materials.
No fluxes, fillers, or shielding gases are used in the process, which keeps costs and effort to a minimum. The entire process is also machine-controlled, making it highly precise and 100% repeatable at any time. This also allows for constant monitoring and quality assurance.
How does the friction welding process work?
The friction welding process is divided into 4 phases:
- Phase 1 - The frictional contact phase:
Rotation of the two workpieces clamped in a holder. They are pressed together at the same time. The pressure exerted is determined in advance and depends on the materials.
- Phase 2 - The friction phase:
The contact surfaces heat up due to the rotation of the workpieces relative to each other and the pressure on each other.
- Phase 3 - The forging phase:
The rotation ends. The pressure exerted is further increased. The plasticized material of the two workpieces bonds together.
- Phase 4 - The holding phase:
The workpieces are now held together under constant pressure. They can now cool down slowly and the bond can solidify.
What are the advantages of friction welding?
Friction welding offers the following advantages over other welding processes:
- Homogeneous joints: Friction welding produces joints that are completely homogeneous across the entire joint surface.
- High-quality connections: The homogeneous connections are very clean and secure. They are also correspondingly durable and stable.
- The metals: Friction welding makes it easy to join different metals together.
- No melting: The materials from which the workpieces are made do not melt during the process.
- No changes: Without additives, there are no changes in the materials. No additive is introduced, which means that the weight of the workpieces does not increase. Furthermore, there is no melt pool that could lead to thermal distortion.
- Fast connections: The connections are highly integrated and can be created quickly.
- Cost-effective: Without the use of additives and thus consumables, friction welding is usually cheaper to use than other processes.
- Machine-controlled: All processes are controlled by machines. This makes them easy to monitor and repeat. It also eliminates human error.
- Preparation: Since impurities are simply pressed out, the preparatory work involved in this process is much less critical for the end result and can therefore be carried out more quickly and at lower cost.
- For all quantities: The process can be easily applied to individual items, such as prototypes, as well as to series and mass production.
Other welding processes
