|About this Abstract
||3rd World Congress on High Entropy Alloys (HEA 2023)
||Computational Thermodynamics-guided Alloy Design and Phase Stability In Non-equimolar Cocrfemnni Multi-principal Element Alloys: An Experimental-theoretical Study
||David D. S. Silva, Gustavo Bertoli, Nelson D. C. Neto, Michael J. Kaufman, Amy J. Clarke, Francisco G. Coury, Claudemiro Bolfarini
|On-Site Speaker (Planned)
||David D. S. Silva
The formation of sigma phase (brittle and undesirable) is a real concern when engineering face centered cubic (FCC) alloys subjected to operation at elevated temperatures (600-1000 °C). Therefore, predicting its formation is essential in alloy design. Phase equilibria were studied in a wide range of compositions by the CALPHAD method in combination with two empirical methods for predicting sigma phase formation (valence electron concentration (VEC) and paired sigma-forming element (PSFE)). Isothermal aging treatments at 900 ºC, 1000 °C and 1100 °C for 20 h were selected, due to the fact that CALPHAD and Tsai criteria predictions for sigma phase formation diverged in some cases. Both prediction methods (CALPHAD and Tsai criteria) were compared with experimental characterization by a combination of synchrotron high energy X-ray diffraction (HEXRD) and electron backscattering diffraction (EBSD). This work will guide further studies of CoCrFeMnNi alloys potentially sensitive to sigma phase formation.
||Planned: Metallurgical and Materials Transactions