Contract Welding Services
We offer Friction Stir Contract Welding services from development through production, providing new solutions to challenging applications.
Friction Stir Welding Machines
MTI builds machines for various industrial applications using the latest STIRTEC Friction Stir Welding technology.
What is Friction Stir Welding?
Revolutionizing Manufacturing Challenges
Friction Stir Welding is a solid-state joining process in which a spinning pin tool traverses across the bond line between two parts, forming a high-quality joint.
It’s a growing technology revolutionizing manufacturing challenges with its unique abilities. From electric vehicles on the ground to ships at sea and rockets in space, FSW delivers high-strength, low-distortion joints that transform assemblies across industries.
With decades of experience, MTI and STIRTEC are partnering to lead the way in friction stir welding (FSW) innovation, offering end-to-end solutions—from part development to high-performance FSW machines. For aluminum alloys, our processes align with the internationally recognized DIN EN ISO 25239 (Parts 1–5), ensuring quality and consistency at every step.
As industries continue to push the boundaries of what’s possible, we’re here to help you reach your production goals—whether by building a machine that makes your part, making the part for you, or helping you make it even better.
Friction Stir Welding
Revolutionizing Manufacturing Challenges
Friction Stir Welding is a solid-state joining process in which a spinning pin tool traverses across the bond line between two parts, forming a high-quality joint.
It’s a growing technology revolutionizing manufacturing challenges with its unique abilities. From electric vehicles on the ground to ships at sea and rockets in space, FSW delivers high-strength, low-distortion joints that transform assemblies across industries.
With decades of experience, MTI and STIRTEC are partnering to lead the way in FSW innovation, offering end-to-end solutions from part development to high-performance FSW machines globally. As industries continue to push the boundaries of what is possible, we are here to help you reach your production goals by building a machine that makes your part, making the part for you, or by helping you make the part even better.
Learn About Tool Selection and Which Tool Design is Right for your Next FSW Project.
Friction Stir Welding Vs Fusion
Fusion welding has long been the traditional joining method across industries. However, advances in welding engineering have led to the development of Friction Stir Welding.
Unlike fusion welding, Friction Stir Welding does not create a weakened heat-affected zone (HAZ). Instead, the joint is formed from the parent materials themselves, resulting in a fine-grain microstructure with mechanical properties that often match or exceed those of the base material.
| Feature | Friction Stir Welding | Traditional Fusion (MIG/TIG) |
|---|---|---|
| Defect Rate | Low | Medium |
| Strength | High/Parent Material | Lower/Heat Affected |
| Fumes | None | High |
| Consumables | Pin Tool | Wire/Gas |
Friction Stir Welding Joint Geometries
Friction Stir Welding can join a wide range of part geometries
Are Your Materials Compatible with Friction Stir Welding?
Friction Stir Welding enables you to join dissimilar metals, opening up possibilities for your industry. If you don’t see your material below, it doesn’t mean it can’t be done.
Utilize MTI’s FSW Contract Welding services to test your materials for strength and stability. Our in-house metallurgy lab enables you to discover its physical properties and capabilities.
Learn More About the Tools Behind Friction Stir Welding
Get straightforward answers to the most commonly asked questions about FSW tool implementation including:
- Types of FSW Tools
- FSW Tool Materials
- Selecting the Right FSW Tool
- Future Trends in FSW Tool Technology
How FSW Works
Friction Stir Welding is more of a forging process than an actual welding process, and simply uses a spinning pin tool and axial forge force to create a bond between two pieces. Key aspects of the process include the following:
Friction Stir Welding uses a special spinning bit called a pin tool. The tool consists of a cone-shaped pin that spins and “stirs” the two materials being joined. A larger diameter shoulder located at the top of the cone provides the friction (heat) and the force to direct the flow of the spinning material being joined.
The process starts by inserting the non-consumable spinning pin tool bit into the two pieces of material being joined.
The pin tool’s design geometry and rotation creates friction that heats the material so it softens to a plastic state, but does not melt.
As the pin tool runs along the weld joint, it extrudes material in a distinctive flow pattern and forges the material in its wake. As the process name implies, the two materials are literally stirred together.
The resulting solid-state bond joins the two pieces into one and is made solely of parent material.
The grain structure in the weld zone is finer than that of the parent material and has similar strength, bending, and fatigue characteristics.
How FSW Works
Friction Stir welding is more of a forging process than an actual welding process, and simply uses a spinning pin tool and axial forge force to create a bond between two pieces. Key aspects of the process include the following.
Friction Stir welding uses a special spinning bit called a pin tool. The tool consists of a cone-shaped pin that spins and “stirs” the two materials being joined. A larger diameter shoulder located at the top of the cone provides the friction (heat) and the force to direct the flow of the spinning material being joined.
The process starts by inserting the non-consumable spinning pin tool bit into the two pieces of material being joined.
The pin tool’s design geometry and rotation creates friction that heats the material so it softens to a plastic state, but does not melt.
As the pin tool runs along the weld joint, it extrudes material in a distinctive flow pattern and forges the material in its wake. As the process name implies, the two materials are literally stirred together.
The resulting solid-state bond joins the two pieces into one and is made solely of parent material.
The grain structure in the weld zone is finer than that of the parent material and has similar strength, bending, and fatigue characteristics.
Advantages & Benefits
Versatile Solution for Various Applications
MTI’s Friction Stir Welding process development and part production is making a dramatic impact across many industries, including aerospace, defense, transportation, rail, marine, and electronics. Here are a few reasons why.
Provides New Solutions to Challenging Applications
The leading-edge technology of Friction Stir Welding allows us to continually identify new joining applications for extrusions, castings, plates, and sheets for customers ranging from railcars to aerospace. Our skilled team is knowledgeable in the applications best suited for FSW and offers solutions to improve product performance, quality, and weld development.
The leading-edge technology of Friction Stir Welding allows us to continually identify new joining applications for extrusions, castings, plates, and sheets for customers ranging from railcars to aerospace. Our skilled team is knowledgeable in the applications best suited for FSW and offers solutions to improve product performance, quality, and weld development.
Friction Stir Welding produces a weld with high weld strength and toughness, plus a fine grain structure that resists fatigue stress. Due to the low heat and small heat-affected zone, there is minimal distortion of the joined parts, reducing the costs associated with preparing the part for subsequent use.
As a solid-state process, Friction Stir Welding eliminates many of the defects associated with conventional fusion welding techniques such as shrinkage, solidification cracking, and porosity. The bond between the two pieces is made solely of the original material, giving it similar strength, bending, and fatigue characteristics of the parent material.
Our large panel production machine is equipped with dual upper and lower weld heads for extrusions or panels that require a top and bottom welded assembly. Welding a large panel or part assembly on both sides saves time and money.
Friction Stir Welding is environmentally friendly, with a process that features low energy input and requires no consumables, flux, filler material, or shielding gases to run, like conventional welding methods. Friction Stir Welding also does not emit smoke, fumes, or gases that need to be exhausted on the back end.
Friction Stir Welding Applications Across Industries
Friction Stir Welding enables new levels of innovation across industries by joining complex geometries and dissimilar materials through a high-strength, solid-state welding process with exceptional consistency and repeatability.
Aerospace
Joins high-strength aluminum alloys, including 2xxx and 7xxx series, without degrading material properties—ideal for lightweight, fatigue-critical structures.
Rails & Coaches
Delivers strong, consistent joints for structural and mechanical components in rail vehicles, essential to passenger safety and service life.
Astrospace
Produces defect-free, leak-tight welds for large, precision components where structural integrity and thermal stability are mission-critical.
Automotive
Joins high-strength aluminum alloys, including 2xxx and 7xxx series, without degrading material properties—ideal for lightweight, fatigue-critical structures.
Consumer Products
Enables clean, repeatable welds with excellent surface finish for aluminum enclosures and assemblies where appearance and consistency matter.
Defense
Provides reliable, high-integrity joints for critical applications requiring exceptional strength, fatigue resistance, and process control.
Electric and Hybrid Vehicles
Creates leak-tight, thermally stable joints for battery trays, enclosures, and cooling systems while supporting scalable, automated manufacturing.
Contract Friction Stir Welding
There is no better place to test the feasibility of your project. With 117,000 square feet of production space, a metallurgical lab, and in-house machines, we have the resources to complete your project in one place.
Contract Friction Stir Welding
There is no better place to test the feasibility of your project. With 117,00 square feet of production space, a metallurgical lab, and in-house machines, we have the resources to complete your project in one place.
Friction Stir Welding Machines
MTI is a global manufacturer of Friction Stir Welding machines. FSW can join a wide range of applications in various industries with high resistance to fatigue stress.
Friction Stir Welding Machines
MTI is a global manufacturer of Friction Stir Welding machines. FSW can join a wide range of applications in various industries with high resistance to fatigue stress.
Common Parts
Friction Stir Welding can join a wide range of parts and geometries
Application
Hybrid Heat Exchanger Box
Application
Aluminum Extrusion for Rail
Application
EV Battery Tray
Application
Cold Plate
Application
Electronic Enclosure
Application
Tailor Welded Blank
Friction Stir Welding FAQs
Friction Welding is a solid-state joining process that uses heat generated by mechanical friction—rather than melting—to join materials. The technology includes several methods, such as Rotary Friction Welding, Linear Friction Welding, Friction Stir Welding, and Low Force Friction Welding.
Friction Stir Welding is a specialized form of friction welding in which a rotating, non-consumable pin tool “stirs” the materials together along the joint line, creating a high-strength bond without melting the base materials.
The strength of a friction stir weld depends on the materials being joined and the selected process parameters. When properly developed and controlled, friction stir welds can achieve up to 100% of the base-metal tensile strength in steels and advanced aluminum alloys, often with superior fatigue performance compared to fusion welds.
Friction Stir Welding is generally stronger than Tungsten Inert Gas (TIG) welding, especially for aluminum alloys and similar materials. As a solid-state joining process, FSW can achieve tensile strengths of up to 100% of the base material, with improved fatigue resistance and a significantly narrower heat-affected zone. Because the material is not melted, FSW avoids grain coarsening and porosity issues that are commonly associated with TIG welding.
Friction Stir Welding does not require shielding gas. Since FSW plasticizes the material rather than melting it, no molten weld pool is created, eliminating the need for gas protection against oxidation, unlike traditional arc welding processes.
75mm plates have been joined in a single pass. Welding from both sides of the same plate can nearly double the thickness of a single-pass weld and allow a much faster feed rate.
With aluminum, FSW is generally faster than MIG/TIG. FSW can achieve feed rates over 5m/min in practical industrial applications. For any welding process, there is a parameter range that will yield desirable results.
The faster the welding feed, the narrower the range becomes. By manipulating the FSW tool characteristics and exploring the welding parameter range, the best location within the process window will yield the fastest feed rate while maintaining quality output. Proper weld development is key to getting the most from the FSW process.
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