About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Electro-Spheroidization Effects on Mechanical and Corrosion Properties in S50C Medium-Carbon Steels: A Comparison With Conventional Subcritical Spheroidization |
| Author(s) |
Meng-Chun Chiu, Chih-An Wu, Chien-Lung Liang |
| On-Site Speaker (Planned) |
Meng-Chun Chiu |
| Abstract Scope |
Direct-current treatment (2.75-4.25 × 10^3 A/cm^2, 1 h) induced spheroidization in normalized S50C medium-carbon steels, with comparable micro-hardness at significantly reduced peak temperature of 269 oC and required time (decrease by 96%) in comparison to conventional subcritical spheroidization (700 oC, 24 h). Lamellar cementite fragmented then ripened, increasing spheroidization rate from 3.4% to 99.5% and widening interlamellar spacing from 0.37 µm to 1.45 µm. EBSD further confirmed recrystallization and grain growth of ferrite from 3.9 µm to 6.8 µm. A comprehensive Hall-Petch and Bailey-Hirsch model partitioned softening among grain boundaries, dislocations, and cementite spacing contributions. Thermal benchmarking using the identical thermal history at 269 oC failed to replicate these changes, evidencing dominant athermal electron wind force effects. With electro-spheroidization achieved, corrosion resistance improved: Rct increased to 1885 Ω·cm^2 and icorr decreased to 6.6 µA·cm^-2. Electro-treatment thus demonstrates a rapid and low-temperature route for sustainable processing of carbon steels. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Iron and Steel, Phase Transformations |