scholarly journals Analysis of the Influence of Friction Stir processing on Gas Tungsten Arc Welding of 2024 Aluminum Alloy Weld Zone

Author(s):  
Krishnaja Devireddy et al., Krishnaja Devireddy et al., ◽  
Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4597
Author(s):  
Mohamed M. Z. Ahmed ◽  
Khaled A. Abdelazem ◽  
Mohamed M. El-Sayed Seleman ◽  
Bandar Alzahrani ◽  
Kamel Touileb ◽  
...  

This work investigates the feasibility of using friction stir welding (FSW) process as a groove filling welding technique to weld duplex stainless steel (DSS) that is extensively used by petroleum service companies and marine industries. For the FSW experiments, three different groove geometries without root gap were designed and machined in a DSS plates 6.5 mm thick. FSW were carried out to produce butt-joints at a constant tool rotation rate of 300 rpm, traverse welding speed of 25 mm/min, and tilt angle of 3o using tungsten carbide (WC) tool. For comparison, the same DSS plates were welded using gas tungsten arc welding (GTAW). The produced joints were evaluated and characterized using radiographic inspection, optical microscopy, and hardness and tensile testing. Electron back scattering diffraction (EBSD) was used to examine the grain structure and phases before and after FSW. The initial results indicate that FSW were used successfully to weld DSS joints with different groove designs with defect-free joints produced using the 60° V-shape groove with a 2 mm root face without root gap. This friction stir welded (FSWed) joint was further investigated and compared with the GTAW joint. The FSWed joint microstructure mainly consists of α and γ with significant grain refining; the GTWA weld contains different austenitic-phase (γ) morphologies such as grain boundary austenite (GBA), intragranular austenite precipitates (IGA), and Widmanstätten austenite (WA) besides the ferrite phase (α) in the weld zone (WZ) due to the used high heat input and 2209 filler rod. The yield strength, ultimate tensile strength, and elongation of the FSWed joint are enhanced over the GTAW weldment by 21%, 41%, and 66% and over the BM by 65%, 33%, and 54%, respectively. EBSD investigation showed a significant grain refining after FSW with grain size average of 1.88 µm for austenite and 2.2 µm for ferrite.


2010 ◽  
Vol 117 ◽  
pp. 37-42
Author(s):  
K.Ratna Kumar ◽  
G. Madhusudhan Reddy ◽  
K. Srinivasa Rao

In this work, it was intended to improve the corrosion resistance of welds of A356 and AA6061 by adopting mainly a special welding techniques, viz., pulsed current gas tungsten arc welding (PCGTAW), electron beam welding (EBW) and friction stir welding (FSW). It was found that the corrosion resistance of A356 and AA6061 welds could be improved by PCGTAW technique rather than continuous current gas tungsten arc welding (CCGTAW). It can be further improved by using electron beam welding. Improved corrosion resistance in A356 welds could be obtained by selecting T6 temper rather than as cast condition. In the case of AA6061, improved corrosion resistance was achieved by selecting T4 temper rather than T6 temper. As for as the welding techniques, friction stir welding (FSW) is useful than fusion welding techniques like CCGTAW,PCGTAW and EBW for improving the corrosion resistance of both the welds.


2013 ◽  
Vol 302 ◽  
pp. 452-456
Author(s):  
Shih Jeh Wu ◽  
Chiao Wei Chung ◽  
Chen Ming Kuo

7075 aluminum alloy is one of the most popular materials for structure. There are lots of demands for welding these structural materials. During the fast high temperature heating and cooling process serious residual stress is generated that causes the deterioration of structure strength. In this study, we investigate the residual stress induced in 7075 aluminum alloy after gas tungsten arc welding. X-ray diffraction method is applied to measure the residual stress under different joint angles. The angular distortion is also measured by a 3-D imaging system. Results show that both residual stress and angular distortion increase with the preparation angle.


Sign in / Sign up

Export Citation Format

Share Document