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

1994 ◽  
Vol 29 (15) ◽  
pp. 3997-4000 ◽  
Author(s):  
Wang Fengquan ◽  
Chen Shiyu ◽  
He Deping ◽  
Wei Bingbo ◽  
Shu Guangji
Crystals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
Xia Tang ◽  
Botao Liu ◽  
Yue Yu ◽  
Sheng Liu ◽  
Bing Gao

The difficulties in growing large-size bulk β-Ga2O3 single crystals with the Czochralski method were numerically analyzed. The flow and temperature fields for crystals that were four and six inches in diameter were studied. When the crystal diameter is large and the crucible space becomes small, the flow field near the crystal edge becomes poorly controlled, which results in an unreasonable temperature field, which makes the interface velocity very sensitive to the phase boundary shape. The effect of seed rotation with increasing crystal diameter was also studied. With the increase in crystal diameter, the effect of seed rotation causes more uneven temperature distribution. The difficulty of growing large-size bulk β-Ga2O3 single crystals with the Czochralski method is caused by spiral growth. By using dynamic mesh technology to update the crystal growth interface, the calculation results show that the solid–liquid interface of the four-inch crystal is slightly convex and the center is slightly concave. With the increase of crystal growth time, the symmetry of cylindrical crystal will be broken, which will lead to spiral growth. The numerical results of the six-inch crystal show that the whole solid–liquid interface is concave and unstable, which is not conducive to crystal growth.


1988 ◽  
Author(s):  
S B. Trivedi ◽  
T S. Ananthanarayanan ◽  
R G. Rosemeier ◽  
J J. Kennedy

2010 ◽  
Vol 638-642 ◽  
pp. 2251-2256 ◽  
Author(s):  
H.P. Jin ◽  
Jia Rong Li ◽  
Shi Zhong Liu

The effects of thermal physical parameters and boundary conditions on investment solidification parameters were obtained using a computer simulation system. Directional solidification parameters of single crystal superalloy include the temperature distribution, the position and the shape of the solid/liquid interface in the mushy zone of the solidifying blade casting. Commercial finite-element analysis software, ProCAST, was used to simulate the solidification processes of the castings of single crystal DD6. The simulation results indicate that the predictions of the temperature show little sensitivity to the thermal physical parameters and boundary conditions. Further, it has also been shown that the location and the shape of solid/liquid interface is related to the boundary conditions of simulation. Increasing the value of interface heat transfer coefficient decreases the width of mushy zone.


2010 ◽  
Vol 129-131 ◽  
pp. 1308-1312
Author(s):  
Ya Hong Zheng ◽  
Yan Lin Wang ◽  
Zi Dong Wang

In the crystal growth process, the temperature distribution and concentration distribution at the solid-liquid interface edge are always the hot problems. In this paper, we study the concentration distribution at the solid-liquid interface edge under the natural convection conditions, we find that the concentration field is oscillating exponential decline or rose along the crystal growth direction. We also study the dendrite morphology of Al-La alloys using the experimental method, the results show that the microstructure of Al-35%La alloys is different from the common microstructure of hypereutectic alloy during the conventional casting process, the first crystalline phase is Al11La3, which composition is discontinuous along the growth direction, the main dendrite is composed of α-Al alternating with Al11La3, the results of SEM and XRD show that the chemical composition along the main dendrite exhibits periodic behavior, therefore, this microstructure is named as periodic diphase dendrite structure.


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