In this episode of MTI’s Whiteboard Wednesdays, CEO and host Dan Adams explores the mechanics and advantages of Friction Stir Welding. Unlike other friction welding processes, in which one component typically moves, Friction Stir Welding keeps both parts stationary while a rotating, non-consumable pin tool generates the heat needed to forge the materials together. The video demonstrates how this technology is particularly effective for joining thin materials—even those under 1 millimeter. It also creates cost-effective, wide components from smaller hollow extrusions. By avoiding the melting and re-solidification associated with fusion welding, this solid-state process maintains the parent material’s strength without adding unnecessary mass.
To learn more about the specifications and capabilities of this process, please visit our Friction Stir Welding Technology page.
Thanks for joining me for MTI’s Whiteboard Wednesdays. I’m Dan Adams. Today, we’re talking about Friction Stir Welding. Friction Stir Welding is another example of a friction welding technique. Friction Welding uses high force and relative motion in order to create heat in order to forge two parts together. In the other friction welding processes that we’ve talked about, one of the two parts is typically moving. In Friction Stir Welding, both parts are stationary.
We use a non-consumable pin tool with a similar geometry to this marker. The shoulder of the tool would ride along the surface and input most of the heat as it’s rotating. There is a pin that penetrates into the material, a little shorter than the depth of material, and as this is rotating, it leaves a forged wake of material in its path. You can also weld top and bottom in the case of this hollow extrusion.
Friction Stir Welding can be used to weld very thin materials; this is four separate pieces of aluminum sheet metal welded along these three seams. Now these can be very wide, and they can be very long. Friction Stir Welding can also be used to weld very thin materials down below one millimeter in thickness.
Friction Stir Welding is also very helpful for welding extrusions; these are three separate hollow extrusions welded along these seams. Now this extrusion can also be very long and can be very wide. It’s cost-effective to weld these separate extrusions together because smaller extrusions are much less expensive than really wide extrusions.
So why would I use Friction Stir Welding instead of fusion welding? Well, if I use a fusion weld here, I’m going to get melting. Melting means re-solidification, which is going to weaken the parent material. So, in order to get the same joint strength of a solid-state bond, a fusion weld would require more material at the welding section. This adds mass. Remember, if this is a really long or a really wide part, that extra mass is really going to add up over time. So you can get the same strength of joint out of a Friction-Stir Weld using less material. This is cost savings for the same performance.
Thank you for joining us for this episode of MTI’s Whiteboard Wednesdays. For more information on this topic or other Friction Welding solutions, please visit our website at mtiwelding.com.