About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Concentrated Sliding Friction Strengthened Dissimilar Stainless Steel/Ti Interface via Phase Transformation During Ultrasonic Spot Welding |
| Author(s) |
Jhe-Yu Lin, Jhe-Chen Liao, Dong-Yu Wu, Cheng-Chang Hsieh, Yun-Ta Chung |
| On-Site Speaker (Planned) |
Jhe-Yu Lin |
| Abstract Scope |
This study investigates the effect of weld size on interfacial strength during ultrasonic spot welding of 316L stainless steel to pure titanium under constant clamping force. Reducing weld area from 10×10 mm to 7×7 mm concentrated sliding friction, resulting in enhanced heat generation and accelerated temperature rise. The smaller weld area achieved peak temperatures of 830°C, exceeding the β-transus point (595°C), which triggered α-to-β phase transformation in titanium through diffusion of β-stabilizer elements (Fe, Cr, Ni) from stainless steel. This phase transformation eliminated interfacial defects and improved joint deformability, increasing interfacial strength by 37% from 1817 N to 2485 N. Microstructural analysis revealed formation of β-Ti and Fe2Ti intermetallic layers at the interface. The larger weld area resulted in insufficient temperature rise, leading to internal fractures in α-Ti and reduced strength. These findings demonstrate that concentrated energy input through reduced weld area effectively enhances joint integrity via controlled phase transformation. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Joining, Iron and Steel, Titanium |