Couples and pairs formation-thermodynamic and kinetic modelling applied to Al-Mg-Si

0506813 - ÚFM 2020 RIV GB eng J - Článek v odborném periodiku
Svoboda, Jiří - Shan, Y. V. - Kozeschnik, E. - Fischer, F D.
Couples and pairs formation-thermodynamic and kinetic modelling applied to Al-Mg-Si.
Modelling and Simulation in Materials Science and Engineering. Roč. 25, č. 6 (2017), č. článku 065011. ISSN 0965-0393. E-ISSN 1361-651X
Grant CEP: GA ČR(CZ) GA15-06390S
Institucionální podpora: RVO:68081723
Klíčová slova: grain-boundary diffusion * self-consistent model * solid-solutions * alloys * precipitation * behavior * 1st-principles * simulation * elements * modelling * thermodynamic extremal principle * bulk diffusion * kinetics * aluminium alloys * cluster-assisted nucleation
Obor OECD: Thermodynamics
Impakt faktor: 1.793, rok: 2017
Způsob publikování: Omezený přístup
https://iopscience.iop.org/article/10.1088/1361-651X/aa76cf

Kinetics of formation of couples (B-C) and pairs (B-B, C-C) is studied in an alloy with B-atoms and C-atoms as dilute solutes and A-atoms as solvent. The trapping concept, allowing division of the system into subsystems, the Bragg-Williams approximation used for the configurational entropy of each subsystem, and the thermodynamic extremal principle are applied in the model. The derived equilibrium conditions provide an extended Oriani-type equation. The kinetics of couples and pairs formation is given by explicit ordinary differential equations for the concentrations of couples and pairs allowing calculation of all relevant state variables. The concept is applied to an Al-Mg-Si system with the bonding energy terms EBB, ECC, EBC taken from ab-initio calculations. The presence of excess vacancies that are eventually frozen in by instant quenching as well as their subsequent annihilation influence the formation kinetics in a decisive way.
Trvalý link: http://hdl.handle.net/11104/0300806