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The local yielding behavior in base metal, heat-affected zone, fusion boundary region, and weld metal of low-alloy steel/Alloy 625 filler metal welds was quantified using digital image correlation instrumented cross-weld tensile test. The tested welds exhibited undermatching, matching, or overmatching weld metal yield strength with significant gradients in the local yielding behavior. An undermatching weld yielded at 69 MPa below the base metal yield stress, accumulating to 0.72% total strain. The base metal in an overmatching weld had 110 MPa lower yield strength than the weld metal. The strong strain hardening response in the Alloy 625 weld metal, within the uniform elongation range, and its constraining effect on the fusion boundary region and heat affected zone, led to extensive strain accumulation, necking, and final failure in the base metal of all tested welds. The yielding behavior of the tested welds was compared to stress-based criteria, utilizing minimum specified and as-delivered yield and ultimate tensile strength, and to strain-based criteria. The capability of digital image correlation instrumented cross-weld tensile testing to quantify local yielding and strain accumulation demonstrates potential application in proving conformity to stress-based and strain-based design criteria of dissimilar and matching filler metal welds.
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Behavior and Relationships between Residual Stresses and Mechanical Properties in Welded Joints of Aluminum Alloy AA5083-H116 Using Pulsed Gas Metal Arc Welding
This work discusses several aspects of the weldability of AA5083-H116 butt-welded joints, using ER5183 filler material, automated GMAW-P process, and 80Ar19He1O2 shielding gas. The used methodology included the characterization of base metal, the development of welded joints using two different heat inputs, the microhardness profiles analysis on the cross section of the welded joint, and the microstructural evolution using microscopy. The above-mentioned measurements were complemented with residual stress evaluation using the x-ray diffraction technique, together with analysis of transversal and longitudinal tensile tests of the welded joints. The obtained results in welded joints indicated that yield strength, ultimate tensile strength, and ductility behavior have been influenced by heat input compared to base metal and reported values for similar alloys. Residual stress results showed that both the weld metal and adjacent coarse grain zone were subjected to tensile stresses, while the refined grain zone (FGZ) and base metal adjacent to the FGZ were subjected to compressive stresses. Additionally, the magnitude of residual stresses was smaller than maximum tensile stresses, and its behavior was related to both heat input and mechanical properties along welding regions.
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- PAR ID:
- 10591452
- Publisher / Repository:
- ASM International
- Date Published:
- Journal Name:
- Journal of Materials Engineering and Performance
- Volume:
- 33
- ISSN:
- 1059-9495
- Page Range / eLocation ID:
- 3912 to 3919
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s11665-023-09082-y
