About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Stability, Phase Transformations, and Reactive Phase Formation in Electronic Materials XXVI
|
| Presentation Title |
Concentrated Sliding Friction Strengthened Dissimilar Stainless Steel/Ti Interface via Phase Transformation During Ultrasonic Spot Welding |
| Author(s) |
Yan-Lin Zhu, Jhe-Yu Lin, Jhong-Ren Huang |
| On-Site Speaker (Planned) |
Yan-Lin Zhu |
| Abstract Scope |
This study investigated the influence of weld area size on heat input, interfacial microstructure, and mechanical strength during ultrasonic spot welding of 316L stainless steel to pure titanium under a constant clamping force of 3000 N. Two horn sizes (10×10 mm² and 7×7 mm²) were compared across welding energies of 200–1800 J. A larger weld area promoted early-stage bonding through local plastic flow but dispersed clamping force, limiting peak interfacial temperature to approximately 540°C and causing internal fractures within the Ti substrate at prolonged welding. In contrast, the smaller 7×7 weld area concentrated heat input, achieving a peak temperature of 883°C that exceeded the Fe-Ti β-transus point (595°C). This triggered α-to-β phase transformation in Ti through diffusion of β-stabilizing elements from 316L, eliminating interfacial defects and forming a deformable β-Ti layer with Fe₂Ti intermetallic compound. Consequently, peak interfacial strength increased by 37%, from 1817 N to 2485 N. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Phase Transformations, Joining, Characterization |