Friction Stir Welding: A Sustainable Solution

In the automotive industry where fuel economy rules, the mass of a car is an important factor when making a purchase. It takes more fuel and energy to move a heavier vehicle, so new technologies are continually being developed in order to reduce energy and fuel consumption. Now, with the increase in electrical vehicle manufacturing, some vehicles consume little to no fuel, but require a lighter body in order to run on electricity. Since every component of a vehicle adds to its weight, it’s important to consider all of the ways the automobile is manufactured, and zoom in on different steps in the process that can be altered to provide a lighter, more fuel-efficient mode of transport.

Clean Welding Challenge
Take the welding process, for example: many parts of manufacturing a vehicle depend on the marriage of metals. In traditional arc, MIG, and TIG welding, metals are fused using intense heat and a molten filler metal. When the metals cool and solidify, a bond is created between all of the materials. This process creates a strong weld, but adds weight to the original material. Additionally, arc, MIG, and TIG welding use a great deal of energy to produce heat to melt the metals. In some cases, the heat used to weld two surfaces warps the part, causing the part to be rejected, and ultimately wastes time, money, and material. As the world moves towards cleaner modes of transport, changes in the way materials are welded are necessary.

A Sustainable Solution
Friction Stir Welding (FSW) uses a solid-state process to join two facing surfaces. The weld head spins into the metal, and with added pressure, friction generates heat between the two surfaces, softening them enough to be mixed. The softened metal is joined much like clay. Instead of turning the material to a molten state, FSW moves material into a plastic state, which completes the weld process using less heat than other welding methods. This process does not require any consumables since the weld tip does not wear out. It’s more manageable, predictable, and controllable. Friction stir welding performs welds of the highest quality and strength, and can even join dissimilar materials.

Through years of research and practice, the use of FSW has gained popularity and is now being used across multiple industries to create strong, seamless welds on structures—aluminum, for example, which requires superior weld strength without a heat treatment.

Friction Stir Welding at JR Automation
At JR’s Quality Drive facility, the PaR Systems I-Stir, a top-of-the-line friction stir welder is being used to join two aluminum plates side-by-side, using a nickel-cobalt alloy pin to stir the aluminum. The aluminum plates will eventually become a large component of a car. Since the product has no added material, the end result, post-weld, is a lighter, more energy-efficient vehicle.