| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Accelerated Testing to Understand the Long Term Performance of High Temperature Materials
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| Presentation Title |
Dynamic Twinning and its Contribution to Enhancing High-temperature Mechanical Properties of the Modified Ni-base Superalloy |
| Author(s) |
Jae Bok Seol, Hyoju Bae, Wonhui Jo, Saurabh Tiwari, Joong Eun Jung, Won-Seok Ko, Jae-Hoon Jang, Jong Bae Jeon, Bong-Ho Lee, Jun-Seob Lee, Hyun-Uk Hong, Young-Kook Lee |
| On-Site Speaker (Planned) |
Jae Bok Seol |
| Abstract Scope |
We modified the chemical composition of Inconel 738LC to reduce its high Co content and enhance mechanical properties at high temperatures. The modified alloy exhibited a 12% increase in tensile strength across a range of temperatures (room temperature to 932 ℃) and demonstrated improved creep resistance under two creep conditions (932 ℃/200 MPa and 750 ℃/600 MPa). Microstructure analysis using STEM and APT techniques revealed the presence of microtwins and local phase transformations within the γ' precipitates, contributing to the strength. Additionally, our analysis provided direct evidence of Cr segregation along microtwins and dislocation cores. These findings provide detailed insights into the formation of microtwins, local phase transformations, and superfast diffusion along twin boundaries at high temperatures. They have the potential to significantly enhance the mechanical properties of nickel-based polycrystalline superalloys. This study unveils a new strengthening mechanism and offers direct evidence for the development of innovative high-temperature polycrystalline superalloys. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Temperature Materials, Characterization, Phase Transformations |