Effect of the High Rotating Magnetic Field (min. 30 mT) on the Unidirectionally Solidified Structure of Al7Si0.6Mg Alloy

The topic of this paper is the unidirectional solidification of ternary Al7Si0.6Mg aluminium alloy in a rotating magnetic field of 30 -150 mT and the characterisation of effect of stirring on the solidified structure. During performing the experiment-series, one of the three solidification parameters (temperature gradient, solid/liquid interface velocity and magnetic induction) was continuously changed and the other two of them was kept on a constant value. The effect of these parameters on the developed structures was analysed during the evaluation of the experimental results. Moreover, the extent of Si-macrosegregation as well as the change of the secondary dendrite arm spacing were investigated on the longitudinal and cross-sections of samples as a function of the three basic parameters.

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Effect of High Rotating Magnetic Field on the Solidified Structure of Al–7wt.%Si–1wt.%Fe Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.752.57 ◽

2013 ◽

Vol 752 ◽

pp. 57-65 ◽

Cited By ~ 5

Author(s):

András Roósz ◽

Jenő Kovács ◽

Arnold Rónaföldi ◽

Árpád Kovács

Keyword(s):

Magnetic Field ◽

Interface Velocity ◽

Longitudinal Section ◽

Rotating Magnetic Field ◽

Christmas Tree ◽

Binary Eutectic ◽

Si Content ◽

The One ◽

Solid Liquid Interface ◽

Solid Liquid

Al–7wt.-% Si–1wt.-% Fe alloy was solidified unidirectionally in the Crystallizer with High Rotating Magnetic Field (CHRMF). The diameter of sample was 8 mm and its length was 120 mm. The parameters of solidification were as follows: solid/liquid interface velocity ~0.082 mm/s, temperature gradient 7+/-1 K/mm, magnetic induction 0 and 150 mT, frequency of magnetic field 0 and 50 Hz. The structure solidified without rotating magnetic field (RMF) showed a homogeneous, columnar dendritic one. The structure solidified by using magnetic stirring showed a dual periodicity. On the one hand, the branches of the “Christmas tree”-like structure known from the earlier experiments contained Al+Si binary eutectic. On the other hand, bands with higher Fe- and Si-content formed in the sample, which were at a larger distance from each other than the branches of the “Christmas tree” structure. The developed microstructure was analyzed by SEM with EDS. The average Si- and Fe-concentrations were measured on the longitudinal section at given places along the length of sample. Furthermore the Si- and the Fe-concentrations close to the bands and among the bands as well as the composition of the compound phases were determined.

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Movement of solid-liquid interface in gallium alloy under the action of rotating magnetic field

Magnetohydrodynamics ◽

10.22364/mhd.49.1-2.23 ◽

2013 ◽

Vol 49 (1-2) ◽

pp. 191-199 ◽

Cited By ~ 4

Author(s):

I. Kolesnichenko ◽

A. Pavlinov ◽

R. Khalilov

Keyword(s):

Magnetic Field ◽

Liquid Interface ◽

Rotating Magnetic Field ◽

Solid Liquid Interface ◽

Solid Liquid ◽

Gallium Alloy

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Transient Conductance Measurements During Pulsed Laser Annealing

MRS Proceedings ◽

10.1557/proc-4-209 ◽

1981 ◽

Vol 4 ◽

Cited By ~ 2

Author(s):

M. O. Thompson ◽

G. J. Galvin ◽

J. W. Mayer ◽

R. B. Hammond ◽

N. Paulter ◽

...

Keyword(s):

Single Crystal ◽

Laser Annealing ◽

Pulsed Laser ◽

Interface Velocity ◽

Laser Pulses ◽

Molten Layer ◽

Pulsed Laser Annealing ◽

Complete Melting ◽

Solid Liquid Interface ◽

Solid Liquid

ABSTRACTMeasurements were made of the conductance of single crystal Au-doped Si and silicon-on-sapphire (SOS) during irradiation with 30 nsec ruby laser pulses. After the decay of the photoconductive response, the sample conductance is determined primarily by the thickness and conductivity of the molten layer. For the single crystal Au-doped Si, the solid-liquid interface velocity during recrystallization was determined from the current transient to be 2.5 m/sec for energy densities between 1.9 and 2.6 J/cm2, in close agreement with numerical simulations based on a thermal model of heat flow. SOS samples showed a strongly reduced photoconductive response, allowing the melt front to be observed also. For complete melting of a 0.4 μm Si layer, the regrowth velocity was 2.4 m/sec.

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Orientation and Velocity Dependence of the Nonequilibrium Partition Coefficient

MRS Proceedings ◽

10.1557/proc-398-113 ◽

1995 ◽

Vol 398 ◽

Author(s):

K.M. Beatty ◽

K.A. Jackson

Keyword(s):

Monte Carlo ◽

Diffusion Coefficient ◽

Partition Coefficient ◽

Interface Velocity ◽

Velocity Dependence ◽

Step Velocity ◽

Equilibrium Partition ◽

Equilibrium Partition Coefficient ◽

Solid Liquid Interface ◽

Solid Liquid

ABSTRACTMonte Carlo simulations based on a Spin-1 Ising Model for binary alloys have been used to investigate the non-equilibrium partition coefficient (kneq ) as a function of solid-liquid interface velocity and orientation. In simulations of Si with a second component kneq is greater in the [111] direction than the [100] direction in agreement with experimental results reported by Aziz et al. The simulated partition coefficient scales with the square of the step velocity divided by the diffusion coefficient of the secondary component in the liquid.

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Solidification parameters of the solid-liquid interface in crystal growth in response to vibration

Journal of Materials Science ◽

10.1007/bf00355960 ◽

1994 ◽

Vol 29 (15) ◽

pp. 3997-4000 ◽

Cited By ~ 12

Author(s):

Wang Fengquan ◽

Chen Shiyu ◽

He Deping ◽

Wei Bingbo ◽

Shu Guangji

Keyword(s):

Crystal Growth ◽

Liquid Interface ◽

Solidification Parameters ◽

Solid Liquid Interface ◽

Solid Liquid

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Crystal Growth Mechanism of YBCO Superconductors Prepared by Unidirectional Solidification Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.2085 ◽

2007 ◽

Vol 546-549 ◽

pp. 2085-2090

Author(s):

En Zhi Gao ◽

Jin Shan Li ◽

Rui Hu ◽

Hong Chao Kou ◽

Hai Tao Cao ◽

...

Keyword(s):

Crystal Growth ◽

Growth Mechanism ◽

Structural Characteristics ◽

Solid State Reaction Method ◽

Optical Microscope ◽

Unidirectional Solidification ◽

Ybco Superconductor ◽

Crystal Growth Mechanism ◽

Solid Liquid Interface ◽

Solid Liquid

Y123 and Y211 powders were synthesized by solid-state reaction method. YBCO superconductor specimens were prepared by unidirectional solidification technique. The microstructure and the structural characteristics were observed by means of the optical microscope, X-ray diffraction (XRD), scanning electron microscope (SEM). The results showed that the specimen have a highly aligned structure, it was observed obvious laminated structure of Y123 crystal. Crystal growth mechanism of YBCO was investigated. Jackson's factor of Y123 crystal was calculated. Interface form was judged tentatively theoretically. The specimen was rapidly quenched by quick pulling. Solid/liquid interface structure was observed. It was concluded that a-b plane was faceted grow forms and layer growing along c-axial on a-b plane.

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