If you’ve been following along with our Whiteboard Wednesday series, you know that traditional friction welding is a great method for joining dissimilar metals — just about any metal that can be formed can be forged.
So, if you’re already successfully joining your bimetallics with traditional friction welding, why would you switch to Low Force Friction Welding?
In this episode, we’ll explain why Low Force Friction Welding could be a better and more efficient option for your dissimilar metal application!
What is Low Force Friction Welding?
Low Force Friction Welding is a solid-state joining technique that uses rotary or linear motion to generate frictional heat between two materials. Once the materials reach the right interface temperature, controlled pressure is applied to create a strong metal joint without melting the base materials.
What sets Low Force Friction Welding apart is its use of an external energy source to preheat the weld interface before the joining process begins. This added heating control reduces the axial force required to bond the materials, making the process especially valuable for thin-walled parts, unique geometries, and select dissimilar metal combinations. It can also eliminate the need for flash removal altogether.
What Is Dissimilar Metal Welding In Solid-State Joining?
Dissimilar metal welding in solid-state joining is the process of joining two different materials to create one part with targeted performance properties. For example, welding aluminum and copper together can produce a component that is conductive, lightweight, and durable—making it valuable for electrical, structural, and manufacturing applications.
However, traditional welding of aluminum and copper can be difficult because the two metals have different melting points and material behaviors. With friction welding of dissimilar metals, the materials do not need to reach a molten state. Instead, this solid-state joining technique brings the materials to a plasticized state, allowing them to bond under controlled heat and pressure.
What Are Microwelds?
Microwelds are high-precision metal joints used for very small components and thin materials. In some applications, this can include materials as thin as 0.5 mm and welds as small as 0.007 mm.
Because microwelding requires precise control of heat, force, and material flow, Low Force Friction Welding can be a valuable solid-state joining technique for research, testing, and advanced manufacturing applications where small-part geometry and consistent joint strength are critical.
Reaping The Benefits Of Low Force Friction Welding Properties
Switching to Low Force Friction Welding for your bimetallics automatically opens the door to this technology’s main benefits such as faster cycle times, lower upset, post-weld heat treatment, and more.
And now, with Low Force, we have the ability to balance or imbalance the input heat, which is beneficial for dissimilar welding.
An Easier Welding Process For Joining Materials
With traditional Rotary Friction Welding, if you wanted to weld a bar to a bar, you would have to rotate one component and apply a forge force against it — that’s really the only way you can balance the heat. If you have two components that have drastically different characteristics (such as a bimetallic application), you have to balance that heat toward the component that’s more difficult to weld.
That process makes it challenging to complete bimetallic welds with traditional friction welding. While we have certainly found ways to do it, Low Force Friction Welding makes for a much simpler process.
With Low Force Friction Welding, we can imbalance the heat so that we can focus it on the component that is more difficult to weld, therefore we have more customization options to make a Low Force weld while still receiving all of the benefits that friction welding provides.
Possible Applications
Tube To Tube: This is an example of an aluminum to steel tube, which simulates a drive shaft.
Bar To Bar: Low Force Friction Welding can also join solid components — this is another aluminum to steel application. You can see how little flash and upset was generated during the weld – a much different result from what we see with traditional friction welding.
Small Components: In a previous episode, we talked about the microwelder at EWI. The application first used on that machine was an aluminum stud to an aluminum plate… but it doesn’t have to be. It can be Copper to Aluminum or even an EV solution. We also have the ability to put multiple studs on a plate.
The benefit of Low Force here is that because the forge force is so low, we can imbalance the heat and make the micro welds without any backside deformation to the very thin plate. Therefore, this is a new application or geometry that cannot be accomplished with traditional friction welding.
A Customer-Tailored Solution
To summarize, we can achieve the same dissimilar combinations with Low Force Friction Welding, but we have a few more levers to pull to improve joint quality. Low Force Friction Welding provides tremendous solid-state joints while also offering all the benefits that make this technology so attractive.
At MTI, our Weld Development 2.0 allows you to experiment and compare welds made with Low Force Friction Welding and traditional friction welding, to make more confident decisions for your part development.
Let’s Get Started
Ready to learn how Low Force Friction Welding can improve your bimetallics? Contact us today to connect with a sales engineer who will help outline your next steps!