Welding is a common industrial process employed to join two similar or dissimilar metals. There are various types of welding methods with each having its own merits and demerits.
However in today’s advanced scenario the aerospace and automotive industries have become very challenging with requirements for light weight yet stronger parts. Hence the welding processes also need to get advanced and improve from conventional methods.
Let’s have a look at two of the most recent and unconventional welding processes namely Friction Welding (FRW) and Friction Stir Welding (FSW).
Friction welding is essentially a metal fusion process in which two metals surfaces are joined by producing heat at the joint area through friction due to relative motion between the parts and simultaneous application of a lateral force which allows the metals to fuse together thus joining them together.
Friction Stir welding though still a metal fusion process but uses a friction stir tool. The tool has a small probe projecting out from the shouldered tool which sits at the joint line of the two metals. The rotation of the tool at high speeds produces friction which in terms produces heat and the metal near the probe goes into plastic deformation region and join together. As the tool moves along the line the preceding metal gets joint due to fusion at plastic temperature region.
Comparison of FSW and FRW
Both the methods are equally capable of producing strong joints. However there are a few differences too.FRW can join both similar and dissimilar material whereas FSW is primarily used for joining Aluminium Alloys. FRW does not produce any heat affected zones (HAZ), like fusion welding, while FSW produces HAZs. FRW has some limitation due to setup required for complex weld geometries however FSW is equally capable for all types of weld geometries.