Thermal-induced Residual Stresses and Distortions in Friction Stir Welds - A Literature Review

Abstract

Friction Stir Welding (FSW) is a solid-state welding technique that uses the heat generated from friction to assemble a wide variety of materials. Irrespective of having a lower heat input as compared to conventional welding techniques, friction stir welds are still prone to significant thermal-induced stresses and distortions owing to the uneven heating and cooling cycles that a weld goes through. Surprisingly, not several reviews have addressed both the residual stresses and distortions of friction stir welds despite their crucial impact on the weld performance. Therefore, the current paper reviews their development, their correlation with process parameters, and ways to reduce them. Moreover, it explains the current status of process modeling and research gaps in the area of interest.

Microstructural and Mechanical Characterization of the Dissimilar AA7075 and AA2024 Aluminum Alloys Reinforced with Different Carbide Particles Welded by Friction Stir Welding

“…Figure 11b shows some small cracks found in the examined images. There are many reasons for these cracks, e.g., the considerable thermal residual stresses in the weld area, which increase the probability of crack formation [38].…”

“…Figure 11b shows some small cracks found in the examined images. There are many reasons for these cracks, e.g., the considerable thermal residual stresses in the weld area, which increase the probability of crack formation [38]. The dissimilar aluminum alloys AA2024 and AA7075 have different material properties, making them susceptible to fracture.…”

Effect of Preheat Temperature and Welding Sequence on the Temperature Distribution and Residual Stress in the Weld Overlay Repair of Hydroturbine Runner

“…Welding overlay is a complex process involving the intersection of heat transfer, material metallurgy, mechanics, and other disciplines. The rapid local heating and cooling during the welding process results in uneven thermal expansion and contraction of the workpiece, which inevitably leads to residual stress and deformation of the workpiece so that the repair quality of the welded structure decreases [ 7 , 8 , 9 , 10 ]. 0Cr13Ni5Mo is a common material for hydraulic turbine runners, which is an ultra-low carbon martensitic stainless steel.…”