About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Alloy Phase Transformations at Elevated Temperatures
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| Presentation Title |
Revealing the origin of twin boundary-induced phase transformation within L1₂ precipitate in Ni-based superalloys |
| Author(s) |
Jae Bok Seol, Joong Eun Jung, Won-Seok Ko, Jae-Hoon Jang, Jong Bae Jeon, Jae Wung Bae, Hyo kyung Sung, Hyoung Seop Kim |
| On-Site Speaker (Planned) |
Jae Bok Seol |
| Abstract Scope |
The dynamic interplay between solutes and planar faults has determined the high-temperature
properties of superalloys. However, quantification of twin boundaries formed during creep tests of L12 particle-hardened superalloys, with their impact on the materials, has not been proven experimentally. We conduct scanning transmission electron microscopy and atom probe tomography to provide direct evidence of physio-chemical features responsible for the high-temperature twin boundaries, including Cottrell atmosphere and Suzuki segregation-associated phase transformation inside L12 particle, for a Ni base superalloy upon creep loading at 930 °C and 200 MPa. Further, we will show that twin boundary initiates the pipe diffusion along energetically dissociated dislocations within L12- ordered structure. These findings will be also discussed through CALPHAD and ab initio calculations. |