Nano-scale phase separation in amorphous Fe-B alloys: Atomic and cluster ordering

Nano-scale phase separation encountered in metallic glasses is investigated for amorphous Fe80B20 and Fe83B17 alloys in an interaction field calculated via electronic theory of alloys in pseudopotential approximation combined with MC equilibration and reverse MC simulation. The phenomenon is identified regarding three topological aspects: (1) pure Fe-clusters as large as similar to 0.9 nm and pure Fe-contours similar to 0.72 nm thick are found to exist; (2) Fe-rich highly deformed-bcc regions are observed; (3) B-centered prismatic units are found to form distinct regions of high and low coordination. Polytetrahedral order prevails for B-prisms. All topological aspects are compiled into a two-dimensional projection model for predicting contributions to short- and medium-range order and corresponding spacing relations. The outcome geometrically involves proportions approximating the golden ratio. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.


Theoretical prediction of bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys
SUER, Sila; Mehrabov, Amdulla; Akdeniz, Mahmut Vedat (Elsevier BV, 2009-03-01)
The bulk glass forming ability (BGFA) of Ti-Cu based multicomponent alloys has been evaluated via theoretical modeling and computer simulation studies based on a combination of electronic theory of alloys in the pseudopotential approximation and the statistical thermodynamical theory of liquid alloys The. magnitude of atomic ordering energies, calculated by means of the electronic theory of alloys in the pseudopotential approximation, was subsequently used for calculation of the key thermodynamic parameters...
YURTSEVER, E; ISSEVER, S (Elsevier BV, 1992-01-01)
Two-dimensional Monte-Carlo simulations of lattice polymers were carried out employing Lennard-Jones (LJ) type intramolecular interactions. The shape-dependent properties of these polymers were studied over a large range of interaction parameters and temperatures. The variation of the critical constant was also analysed. Two-dimensional surfaces of sections were used to determine the portions of the parameter space which corresponded to theta-conditions. The behaviour of LJ polymers far from theta-condition...
Temperature dependent dispersoid stability in ion-irradiated ferritic-martensitic dual-phase oxide-dispersion-strengthened alloy: Coherent interfaces vs. incoherent interfaces
Chen, Tianyi; Gigax, Jonathan G.; Price, Lloyd; Chen, Di; Ukai, S.; Aydoğan Güngör, Eda; Maloy, S. A.; Garner, F. A.; Shao, Lin (Elsevier BV, 2016-09-01)
In this study, the microstructure of a 12Cr ferritic-martensitic oxide-dispersion-strengthened (ODS) alloy is studied before and after Fe ion irradiation up to 200 peak displacements per atom (dpa). Irradiation temperature ranges from 325 to 625 degrees C. Before irradiation, both coherent and incoherent dispersoids exist in the matrix. In response to irradiation, the mean sizes of dispersoids in both the ferrite and tempered martensite phases change to equilibrium values that increase with irradiation temp...
Molecular-dynamics simulations of surface and bulk properties of Zn, Cd, and ZnCd systems
Amirouche, L; Erkoç, Şakir (Wiley, 2004-02-01)
Surface and bulk properties of Zn, Cd, and ZnCd systems have been investigated by performing molecular-dynamics simulations using a recently developed empirical many-body potential energy function for these systems, which comprices two- and three-body atomic interactions. Surface reconstruction and multilayer relaxation on clean surfaces, adatom on surface, substitutional atom on surface and bulk materials, and vacancy on surface and bulk materials have been studied extensively. (C) 2004 WILEY-VCH Verlag Gm...
Phonon dispersions and elastic constants of disordered Pd-Ni alloys
Kart, SO; Tomak, Mehmet; Cagin, T (Elsevier BV, 2005-01-31)
Phonon frequencies of Pd-Ni alloys are calculated by molecular dynamics (MD) simulation. Lattice dynamical properties computed from Sutton-Chen (SC) and quantum Sutton-Chen (Q-SC) potentials as a function of temperature are compared with each other. We present all interatomic force constants up to the 8th nearest-neighbor shell obtained by using the calculated potential. Elastic constants evaluated by two methods are consistent with each other. The transferability of the potential is also tested. The result...
Citation Formats
M. AYKOL, A. Mehrabov, and M. V. Akdeniz, “Nano-scale phase separation in amorphous Fe-B alloys: Atomic and cluster ordering,” ACTA MATERIALIA, pp. 171–181, 2009, Accessed: 00, 2020. [Online]. Available: