– Extreme consistency and repeatability

Once these factors are determined (a quick process for experienced welders), a component can be rapidly reproduced with little interruption in the process, creating extreme consistency and repeatability for nearly any project.

– Minimal preparation of components

A minimally prepared saw-cut surface is suitable for the inertia friction welding process because the displacement of plastic metal eliminates original surface conditions and expels any contaminants from the weld zone.

– Minimal post-welding machining required

The inertia friction welding technique produces near-net shape components that require minimal post-machining. In some cases, a ring of flash metal at the joint may have to be removed.

– Overall faster turnaround time

Simply put, the inertia friction welding process just doesn’t take very long compared to traditional welding or machining techniques.

2. Joining Dissimilar Metals

Normally, the large discrepancy between the melting points of two dissimilar metals (e.g. stainless steel and aluminium; copper and steel) would make them impossible to weld using traditional techniques, and would require some kind of mechanical connection.

The inertia friction welding process does not require the facing surfaces to melt, so when the work pieces become plasticized, pressed together and then cooled (with adjacent non-heated metal acting like a heat sink), the metals form a high-integrity bond with no alloying of the material.

The ability to choose dissimilar metals for a component allows the manufacturer to eliminate the use of expensive metals in parts of the work piece that do not require such a metal.

Not only does this reduce the material cost of the welding process, it can also help the application run more efficiently since the burden of the heavier material is reduced.

3. Cost Reductions Compared to Traditional Welding and CNC Machining

Serious savings are achieved through the inertia friction welding process in both labor hours and material costs.

– Dissimilar metals creates savings

As mentioned, the ability to utilize dissimilar metals can help manufacturers save on material costs by eliminating the need to use expensive metals throughout the entire component.

– Reduced material costs, reduced machining costs

The process requires less raw materials to achieve the same fatigue and torque thresholds of parts formed with other methods.  This means a reduction in both raw materials costs and post-welding machining time to remove extra material.

– Minimal scrap material

Compared to components manufactured with a CNC lathe, inertia friction welding scraps little-to-no material, allowing the manufacturer to purchase significantly less materials to achieve the same volume of production.

– Reduced operational expenses

Costs are reduced by eliminating the need for the gases, filler materials, and fluxes that are required in fusion welding methods. Machining costs are also reduced by lowering tools costs and increasing productivity.

4. High Weld Integrity

Inertia friction welding is a solid-state welding process that allows no possibility for gas porosity or slag inclusions.
Friction welding creates a 100% bond of the contact area, creating joints that are equal in quality to forged bonds. The weld properties are superior to welds created with traditional fusion processes, such as MIG or TIG welding.
The process ultimately creates joint strength that is comparable or even greater to the parent materials.

5. No Quantity Limitations

Inertia friction welding is a cost-effective solution for producing prototype, small runs or large, repeated runs for ongoing projects.

6. Safety of Workers

The elimination of hazardous bright light and splattering molten material significantly decreases the risk of injuries on the floor.

How Inertia Friction Welding Is Best Used

While inertia friction welding is an extremely useful, cost-effective method of joining metals and other materials, it is not suitable for all applications and has a short set of limitations:

• Materials must be malleable at high temperatures
• Limitations arise with the presence of a brittle phase in the structure (e.g. in materials such as graphite, manganese sulfide, free lead, or tellurium)
• Cast iron is excluded from the list of weldable materials
• Bronzes and brasses are excluded from the list when they have a high lead content (> 0.3%)
• Angular orientation of welded parts is not feasible at this time
• The basic joint must be a butt weld
• In general, the joint face on at least one of the parts must be essentially round in shape

Applications That Benefit From Inertia Friction Welding

1. Roller Manufacturing

The inertia friction welding process reduces costs and cycle time for manufacturers that rely on industrial rollers.

• Nip rollers: Nip rolls are powered rolls used to press two or more sheets together, forming a laminated product. The pressure created at the nip point brings the sheets into contact, and squeezes out bubbles or blisters.
• Feed rollers: On a sheet-fed printing press, a feed roller is one of a set of rubber wheels that transports a sheet of paper from the pile table to the grippers.
• Heat transfer rollers: Heat transfer rollers provide temperature control by circulating heated or cooled fluid through coils under the outer shell of the roll. The fluid cools or heats the roll surface to the desired temperature for the application.
• Conveyor rollers
• Pressure/Fuser rollers

2. Drilling and Mining

Read a case study on using Inertia Friction Welding to create drilling rods for a company in the natural gas mining industry:

• Oil drilling
• Natural gas drilling
• Water well drilling

3. Aerospace Components that Require High-Strength Metals

4. Pneumatic Pressure Assemblies