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TYPES OF FRICTION WELDING: A DEEP DIVE INTO MODERN JOINING TECHNIQUES
Friction welding, a category of solid-state welding, has garnered significant attention in the manufacturing sector for its efficiency, versatility, and strength. By harnessing the heat generated from friction between two workpieces, this method achieves robust joints without the need for filler materials. As the demand for high-integrity welds grows, understanding the various types of friction welding becomes paramount. Let’s explore the primary processes in this domain.
1. Rotary Friction Welding (RFW):
The most traditional form of friction welding, RFW, involves one component being rotated at high speed while the other remains stationary. As the rotating component is pressed against the stationary one, frictional heat is generated. Once the desired temperature is reached, the rotation stops, and additional pressure is applied to forge the pieces together. This method is widely used for joining cylindrical components, such as drill rods and drive shafts. Further, RFW consists of the Direct Drive, Inertia, and Hybrid friction welding processes – all of which we do at MTI.
2. Linear Friction Welding (LFW):
In LFW, both workpieces are kept stationary in terms of rotation, but one is oscillated back and forth linearly against the other. The heat generated from this linear motion facilitates the welding process. LFW is particularly popular in the aerospace industry for producing blisks (bladed disks) and other complex components.
3. Friction Stir Welding (FSW):
A relatively newer technique, FSW employs a non-consumable rotating pin tool that is plunged into the joint line of two workpieces. The tool’s shoulder generates heat through friction, while its pin stirs the softened material, creating a joint as it traverses along the weld line. FSW is especially effective for joining non-ferrous metals like aluminium and is widely used in aerospace, automotive, and shipbuilding industries.
4. Low Force Friction Welding:
Low Force friction welding is the newest friction welding process developed and commercialised by MTI. Low Force uses an external energy source to raise the interface temperature of the components being welded, thereby reducing the process forces required to make a solid-state weld compared to traditional friction welding. Additionally, Low Force maintains all of the benefits of traditional friction welding – but in some cases they are multiplied – and new advantages are being identified.
5. Friction Surfacing:
This method involves a rotating consumable rod or wire that is moved across a substrate’s surface. The frictional heat generated softens the rod, depositing material onto the substrate. Friction surfacing is often used for coating or cladding applications to enhance surface properties.
6. Friction Spot Welding:
A derivative of FSW, this technique is used for spot welding applications. A rotating tool is plunged into overlapping sheets, creating a localized joint. It’s an effective method for joining thin sheets, especially in the automotive sector.
Friction welding, with its diverse processes, offers solutions tailored to various industrial needs. Whether it’s joining cylindrical components with RFW or creating high-quality joints in aluminium structures with FSW, friction welding techniques are reshaping the landscape of modern manufacturing. As industries continue to prioritise efficiency, sustainability, and quality, the relevance and applications of friction welding are set to soar. At MTI, we specialise in RFW, LFW, FSW, and Low Force Friction Welding for any of your manufacturing needs.
