Friction stir welding

FSW of Aluminum with PP : Joining different parts is one of the crucial components of designing/engineering of materials. Presently, the current energy efficient low weight automotive and aerospace components consist of a different class of materials, such as metals, polymers, ceramics, etc. Joining these components remains a challenge. Here, we demonstrate metal (aluminum) and polymer (Polypropylene, pp) joining using mechanical friction. The detailed characterization clearly demonstrates that atomically locked interfaces are formed in such joining and no chemical bonds are formed during the joining. Also, a waterproof and strong interface is formed in such a process. Fully atomistic molecular dynamics simulations were also carried out in order to further gain insights on the joining process.

FSW of CuCrZr with 316L Stainless Steel: CuCrZr alloy (Cu-0.8wt-%Cr-0.1wt-%Zr) and 316L stainless steel (Fe-0.03wt-%C-16wt-%Cr-10wt-%Ni) plates were successfully friction stir lap welded resulting in significant mechanical mixing of the two matrix elements, Cu and Fe, in the stir zone. The severe mixing not only led to improved load bearing response but also leads to form Cu-rich and Fe-rich regions in the weld nugget. The formation of these phases governs the failure mechanism of the joint. Tensile properties of the weld showed promising response when compared with joints made for the similar alloy pair by other welding techniques. This suggests strong feasibility of applying FSW for joining Cu and steel for nuclear applications.

Amit Arora
Assistant Professor of Materials Science and Engineering

Amit Arora is Assistant Professor of Materials Science and Engineering at Indian Institute of Technology Gandhinagar. He leads the Advanced Materials Processing Research Group at IIT Gandhinagar which works in the area of numerical modeling of welding and joining processes, additive manufacturing processes, and friction stir welding and processing. The recent works of the groups published in various journals include tool wear during FSW, numerical modeling of dissimilar FSW, and mechanical and electrochemical characterization of friction stir surface composites.