Welding of space and aircraft structures is increasingly becoming a reality, helped by the development of friction stir welding. The space industry quickly recognised the advantages of this process over conventional arc processes, such as the absence of a melt zone, reduced distortion, no porosity, and ease of automation. The welding of the cryogenic fuel tanks of future space vehicles (eg Delta) has now been accomplished with this technology.
Invented and patented at TWI, the process moved from an idea to a production reality in the space of 4-5 years. The process is now widely accepted and significant work is underway throughout the world to prove its capability in more and more applications. The process is well proven for many aerospace aluminium alloys, some up to 75mm thick, carbon manganese steels, magnesium alloys and copper alloys. New work is looking to extend the process to titanium and nickel based alloys.