Special Features of disordering in Crystallization of Two-Component Metal Melts in the Model of Two-Phase Transitive Zone

2014 ◽  
Vol 57 (5) ◽  
pp. 598-614
Author(s):  
Yu. A. Baikov ◽  
N. I. Petrov
Keyword(s):  
Two Phase ◽  
Metal Melts ◽  
Two Component

scholarly journals Особенности микрокристаллизации 50 % двухкомпонентных металлических расплавов в модели переходной двухфазной зоны в диффузионно-релаксационном режиме

2019 ◽  
Vol 21 (2) ◽  
pp. 164-181
Author(s):  
Yury A. Baikov ◽  
Nikolai I. Petrov ◽  
Margorita I. Timoshina ◽  
Evgeniy V. Akimov
Keyword(s):  
Transition Region ◽  
Steady State Solution ◽  
Phase Zone ◽  
Two Phase ◽  
Mathematical Mode ◽  
Metal Melts ◽  
Two Component ◽  
Crystal Transition ◽  
Supercooled Melt ◽  
Metallic Melts

    В диффузионно-релаксационном режиме кристаллизации 50% двухкомпонентных металлических расплавов в модели переходной  двухфазной зоны оценены термодинамические параметры, при которых возможно образование полностью разупорядоченной  двухкомпонентной кристаллической фазы с простой кубической элементарной решеткой стехиометрического состава. Исследована область вблизи точки разупорядочения кристаллической фазы и установлен закон стремления параметра дальнего порядка к нулю при достижении критической температуры (переохлаждения) системы двухкомпонентный расплав-кристалл. Установлены кинетические особенности роста кристаллической фазы в точке разупорядочения. Установлен закон восстановления упорядоченной двухкомпонентной кристаллической фазы во времени. Оценены возможные значения времен релаксации при переходе из разупорядоченной двухкомпонентной кристаллической фазы с простой кубической элементарной ячейкой к полностью  упорядоченной. Установлены кинетические особенности образования полностью упорядоченного двухкомпонентного кристалла.       REFERENCES Sarkisov P. D., Baikov Yu. A., Meshalkin V. P. Matematicheskoe modelirovanie kristallizatsii odno- i dvukhkomponentnykh metallicheskikh rasplavov [The one- and binary metallic melts mathematical mode ling crystallization]. Moscow, Physmatlit Publ., 2003. 378 p. (in Russ.) Baikov Y. A., Petrov N. I. Structure of the Transitive Two-Phase Zone in Crystallization of Two-Component Metal Melts. Russian Physics Journal, 2014, v. 57(4), pp. 459–468. https://doi.org/10.1007/s11182-014-0262-2 Baikov Yu. A., Petrov N. I. Special Features of disordering in Crystallization of Two-Component Metal Melts in the Model of Two-Phase Transitive Zone. Russian Physics Journal, 2014, v. 57(5), pp. 598–614. https://doi.org/10.1007/s11182-014-0282-y Petrov N. I. The Crystal Disordering Study When Growing From the Binary Metallic Melts. National University of Science and Technology «MISiS» Dis. Cand. Phys.-Mat. Sci. Moscow, 2017, 180 p. URL: http:// misis.ru/fi les/6902/Petrov_AR.pdf (in Russ.) Sarkissov P. D., Baikov Yu. A., Meshalkin V. P. Order-disorder processes in crystals when crystallizing binary metallic melts. Doklady Physics, 2003, v. 48(6), pp. 290–295. https://doi.org/10.1134/1.1591316 Chistyakov Yu. D., Baikov Yu. A., Schneider H. G., Ruth V. The order-disorder transformation at supercooled melt/crystal transition region of binary melts (I) the master equation. Crystal Research and Technology, 1985, v. 20(8), pp. 1007–1014. https://doi.org/10.1002/crat.2170200802 Chistyakov Yu. D., Baikov Yu. A., Schneider H. G., Ruth V. The order-disorder transformation at supercooled melt/crystal transition region of binary melts (II) the steady state solution // Crystal Research and Technology, 1985, v. 20(9), pp. 1149–1156. https://doi.org/10.1002/crat.2170200903 Guinier A. J., Griffoul R. Compte Rendu, 1945, v. 221, pp. 121. Guinier A. J. Imperfections of crystal lattices as investigated by the study of X-ray diffuse scattering // Proceedings of the Physical Society, 1945, v. 57(4), pp. 310–324. https://doi.org/10.1088/0959-5309/57/4/306 Schneider H. G. Collection: Advances in Epitaxy and Endotaxy. Akademiai Kiado, Budapest, 1976, p. 23. Chistyakov Yu. D., Baikov Yu. A. Collection: Advances in Epitaxy and Endotaxy. Akademiai Kiado, Budapest, 1976, p. 159. Chistyakov Yu. D., Baikov Yu. A. Collection: Advances in Epitaxy and Endotaxy. Akademiai Kiado, Budapest, 1976, p. 257.

scholarly journals EXCHANGE COUPLING AND ENHANCEMENT OF CURIE TEMPERATURE OF THE INTERGRANULAR AMORPHOUS REGION IN NANO-CRYSTALLINE DUPLEX-PHASE ALLOYS SYSTEM

2007 ◽  
Vol 21 (27) ◽  
pp. 4689-4706
Author(s):  
Y. Z. SHAO ◽  
W. R. ZHONG ◽  
G. M. LIN ◽  
X. D. HU
Keyword(s):  
Curie Temperature ◽  
Exchange Coupling ◽  
Volume Fraction ◽  
Amorphous Region ◽  
Experimental Result ◽  
Dual Phase ◽  
Two Phase ◽  
Nanocrystallite Size ◽  
Nano Crystalline ◽  
Two Component

We studied the theoretical Curie temperature of a dual-phase nanomagnetic system by Monte Carlo simulation of a modified Heisenberg model on a 3D complex lattice consisting of single- and cluster-spins. We also systematically investigated the experimental Curie temperature of a dual-phase nanomagnetic alloy and performed a direct comparison between theory and experiment. The exchange coupling between two component magnetic phases substantially affects the Curie temperature [Formula: see text] of the intergranular amorphous region of a dual-phase nanomagnetic system. The [Formula: see text] depends upon the nanocrystallite size d, the volume fraction Vc and the interspace among crystallites ξ. Large crystallized volume fraction Vc, small grain size d, and thin interphase thickness ξ lead to an obvious enhancement of Curie temperature (ECT) of intergranular amorphous region, whereas the Curie temperature of nanocrystallites [Formula: see text] decreases slightly. By simulation, we worked out a relationship between the reduced ECT and ξ, as [Formula: see text], and it conforms to the experimental result. In addition, we also simulated the demagnetization of a hard–soft nanocomposite system. The exchange coupling between two component phases affects the cooperativity of two-phase magnetizations, the coherent reversal of magnetizations, and coercivity.

scholarly journals Generalized second-order slip for unsteady convective flow of a nanofluid: a utilization of Buongiorno’s two-component nonhomogeneous equilibrium model

2020 ◽  
Vol 9 (1) ◽  
pp. 156-168
Author(s):  
Seyed Mahdi Mousavi ◽  
Saeed Dinarvand ◽  
Mohammad Eftekhari Yazdi
Keyword(s):  
Boundary Layer ◽  
Equilibrium Model ◽  
Second Order ◽  
Model Parameters ◽  
Slip Parameter ◽  
Two Phase ◽  
Convective Boundary ◽  
First Order ◽  
Special Cases ◽  
Two Component

AbstractThe unsteady convective boundary layer flow of a nanofluid along a permeable shrinking/stretching plate under suction and second-order slip effects has been developed. Buongiorno’s two-component nonhomogeneous equilibrium model is implemented to take the effects of Brownian motion and thermophoresis into consideration. It can be emphasized that, our two-phase nanofluid model along with slip concentration at the wall shows better physical aspects relative to taking the constant volume concentration at the wall. The similarity transformation method (STM), allows us to reducing nonlinear governing PDEs to nonlinear dimensionless ODEs, before being solved numerically by employing the Keller-box method (KBM). The graphical results portray the effects of model parameters on boundary layer behavior. Moreover, results validation has been demonstrated as the skin friction and the reduced Nusselt number. We understand shrinking plate case is a key factor affecting non-uniqueness of the solutions and the range of the shrinking parameter for which the solution exists, increases with the first order slip parameter, the absolute value of the second order slip parameter as well as the transpiration rate parameter. Besides, the second-order slip at the interface decreases the rate of heat transfer in a nanofluid. Finally, the analysis for no-slip and first-order slip boundary conditions can also be retrieved as special cases of the present model.

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