Effect of Stress Concentration on Strength and Fracture Behavior of Dissimilar Metal Joints
Dissimilar metal joints tend to fracture along the welded interface during tensile testing, particularly in butt joint configuration. A common explanation relates formation of brittle intermetallic compound layer at dissimilar weld interface to crack initiation and propagation. This typically leads to lower strength and ductility of the dissimilar material joint. However, another critical aspect determining strength and fracture behavior of dissimilar material joints is the existence of stress concentration at the welded interface during mechanical loading. Mismatch of elastic modulus of dissimilar materials creates stress concentration at the initial stage of mechanical loading, which facilitated crack initiation at the welded interface. In this overview, factors leading to stress concentration and their impact on dissimilar joint strength and fracture behavior have been highlighted.
KeywordsDissimilar joining Fracture Stress concentration
This work was supported under the NSF-IUCRC grant for Friction Stir Processing (NSF-IIP 1157754). The additional support of Boeing, General Motors, Pacific Northwest National Laboratory, Army Research Laboratory and Korea Aerospace Research Institute for the UNT CFSP site is acknowledged. This report was prepared as an account of work sponsored by an agency of the US Government. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the US Government or any agency thereof. We also acknowledge the UNT Materials Research Faculty (MRF).
- 1.Kumar N, Yuan W, Mishra RS (2015) Friction stir welding of dissimilar alloys and materials. Butterworth-HeinemannGoogle Scholar
- 14.Wang T, Mageshwari K, Liu K, Mishra RS (2018) Friction stir butt welding of strain-hardened aluminum alloy with high strength steel. Mater Sci Eng AGoogle Scholar