Friction welding
Friction welding is a type of pressure welding in which the components to be joined are rotated relative to each other under controlled axial force.
The resulting frictional heat softens the material at the interface, and under the combined effect of heat and pressure, a solid-state, metallurgical bond is formed at the atomic level.
This process enables the assembly of complex geometries from simple components and allows the joining of dissimilar materials with different chemical compositions or mechanical properties — combinations that are often not feasible with conventional fusion welding methods.
By using friction welding, the application of costly materials can be limited to critical sections of the component, resulting in significant cost savings and optimized material utilization.
The technology is widely used across various industries, including aerospace, automotive, oil and gas, construction, agriculture, defense, electrical engineering, cutting tool manufacturing, nuclear, and general mechanical engineering.
Its capability to deliver strong, repeatable, and high-integrity joints makes it ideal for both prototype development and high-volume serial production in demanding industrial environments.
Examples of the Cost-Efficiency of Friction Welding
The tractor planetary housing consists of a relatively heavy head section and a long shaft.
Traditional manufacturing methods include casting or forging, both of which are labor- and energy-intensive.
The relatively long shaft poses challenges in both forging and casting. For friction welding, the component can be divided into two parts: the housing and the shaft.
The housing is made from forgeable carbon steel, while the shaft, due to higher strength requirements, is made of alloy steel.
After welding, the planetary housing is normalized and finished. The resulting part is equivalent in service life to a forged component, but its production cost is 45% lower.The crankshaft blank is also usually produced by casting or forging. It can be divided into three parts, which can be quickly prepared by cutting.
A crankshaft manufactured using friction welding achieves 60% cost savings compared to cast production and 48% compared to forged production.Cutting tools have working ends made from high-speed steel (HSS) and shanks from carbon steel.
Friction welding provides a precise, crack-free joint between these dissimilar steels.
The welded tool exhibits the same cutting performance as a one-piece tool, while reducing material consumption by 30–40%.Engine valves have wear-resistant stems and heat-resistant alloy heads.
In such components, the axial alignment ensured by friction welding is particularly important.For pump shafts, only one half of the shaft is exposed to corrosion, and diameter variations are common.
Friction welding of stainless steel to a cheaper carbon steel, even with differing diameters, results in significant material and cost savings.In the aerospace industry, combining titanium and nickel-based alloys is difficult with conventional welding methods.
Friction welding, however, allows a precise, contamination-free joint, for example, between fan disks and shafts.Connecting rods have working surfaces made of hardened or chrome-plated steel, while the rear end is made from softer steel.
Friction welding allows these two parts to be joined with high precision, and the joint can withstand alternating loads.
This process eliminates the defects associated with traditional threaded or shrink-fit connections, while reducing manufacturing costs by 20–30%.
