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High-Resolution Residual Stress Mapping of Magnesium AZ80 Friction Stir Welds for Three Processing Conditions
Abstract not provided
Crystallographic orientation data from chloride-induced stress corrosion crack (CISCC) paths in gas tungsten arc welded (GTAW) austenitic stainless steel 304L
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Fatigue behavior of MAG welds of thermo-mechanically processed 700MC ultra high strength steel
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Simulated seismic behavior of welded steel tee joints and elbows used in natural gas networks
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Determining cohesive parameters for modeling interfacial fracture in dissimilar-metal friction stir welded joints
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Integrated modeling for residual stress and failure behavior in welded Grade 91 steel cladded with nickel alloy
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Explosive welding of aluminium to stainless steel using carbon steel and niobium interlayers
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Polysilazane-derived SiON coating on stainless steel weld for corrosion resistance
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Microstructure and microchemistry of laser welds of irradiated austenitic steels
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Nondestructive ultrasonic characterization of a triple-weld-bead wire arc additively manufactured ER70S-6 S-curved wall
Understanding build-scale microstructural variation in wire arc additive manufacturing (WAAM) of low-carbon steels is essential for ensuring consistent structure–property relationships throughout large components. Conventional destructive characterization techniques, such as scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD), are time-intensive and limited to localized regions, making comprehensive evaluation of large WAAM structures challenging. In this study, a nondestructive ultrasonic approach was employed to characterize a 252 mm tall ER70S-6 S-curved WAAM wall produced using a triple-bead deposition strategy. Optical and SEM analysis revealed a repeating dual-region microstructure consisting of uniform polygonal ferrite at melt pool centers and heterogeneous ferrite with coarse and fine grains near melt pool boundaries, attributed to cyclic thermal conditions. Longitudinal ultrasonic backscatter imaging was used to evaluate the continuity of this periodicity along the full build height. The ultrasonic response exhibited a consistent repeating pattern that correlated with the observed layer-wise microstructural variation. X-ray computed tomography confirmed the absence of detectable porosity, indicating that ultrasonic contrast is primarily governed by grain morphology. Overall, the results indicate that longitudinal backscatter ultrasound is a promising nondestructive characterization technique for validating microstructural variations along the s-curved WAAM wall, with significant potential for microstructure optimization and process control.