|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Hume-Rothery Award Symposium: Alloy Phase Chemistry at the Atomic Level - Opportunities and Challenges
||Design and Development of Novel High-temperature Creep Resistant 9% Cr Steels
||Dieter Isheim, Yao Du, Cameron T Gross, Semyon Vaynman, Yip-Wah Chung
|On-Site Speaker (Planned)
Structural steels soften remarkably when heated above several hundred °C due to the transition from athermal dislocation glide to thermally activated glide and diffusion processes accelerating changes of the microstruture critical to strength. We utilize a novel combination of several strategies for the design of 9% Cr steels with reduced carbon concentration to suppress Cr<SUB>23</SUB>C<SUB>6</SUB>, precipitating semi-coherent mono-carbonitride precipitates (MX, M = slow diffusing early transition metal, X = carbon or nitrogen), minimizing the driving force and nucleation of Laves and Z-phases, for enhanced microstructural stability, and addition of Mo and W for solid solution strengthening with the ultimate goal to obtain creep rupture times longer than 100,000 hours at 650°C and 35MPa, for applications in electric power generation. We present results from computational and experimental studies, including atom-probe tomography, phase stability and precipitation kinetics and estimations of the long-term microstructural stability and mechanical properties during exposure to above 700°C.
||Planned: Supplemental Proceedings volume