Numerical results show that an external magnetic field may influence significantly the flow pattern in the molten semiconductor of Czochralski crystal growth. The melt flow could be pronouncedly damped by a magnet. ic...Numerical results show that an external magnetic field may influence significantly the flow pattern in the molten semiconductor of Czochralski crystal growth. The melt flow could be pronouncedly damped by a magnet. ic field with the intensity of several thousands Gauss, while the temperature field is affected only in a less extent by the magnetic field.展开更多
The effect of the pulsed magnetic field on the grain refinement of superalloy K4169 has been studied in directional solidification.In the presence of the solid-liquid interface condition,the distributions of the elect...The effect of the pulsed magnetic field on the grain refinement of superalloy K4169 has been studied in directional solidification.In the presence of the solid-liquid interface condition,the distributions of the electromagnetic force,flow field,temperature field,and Joule heat in front of the solid-liquid interface in directional solidification with the pulsed magnetic field are simulated.The calculation results show that the largest electromagnetic force in the melt appears near the solid-liquid interface,and the electromagnetic force is distributed in a gradient.There are intensive electromagnetic vibrations in front of the solid-liquid interface.The forced melt convection is mainly concentrated in front of the solid-liquid interface,accompanied by a larger flow velocity.The simulation results indicate that the grain refinement is attributed to that the electromagnetic vibration and forced convection increase the nucleation rate and the probability of dendrite fragments survival,for making dendrite easily fragmented,homogenizing the melt temperature,and increasing the undercooling in front of the solid-liquid interface.展开更多
基金supported by the National Natural Foundation of China
文摘Numerical results show that an external magnetic field may influence significantly the flow pattern in the molten semiconductor of Czochralski crystal growth. The melt flow could be pronouncedly damped by a magnet. ic field with the intensity of several thousands Gauss, while the temperature field is affected only in a less extent by the magnetic field.
基金financially supported by the National Natural Science Foundation of China (No. 51674236)the Key Research and Development Program of Liaoning Province (No.2019JH2/10100009)+1 种基金the National Science and Technology Major Project (No.2017-Ⅵ-0003-0073)the National Key Research and Development Program (No.2018Y-FA0702900)。
文摘The effect of the pulsed magnetic field on the grain refinement of superalloy K4169 has been studied in directional solidification.In the presence of the solid-liquid interface condition,the distributions of the electromagnetic force,flow field,temperature field,and Joule heat in front of the solid-liquid interface in directional solidification with the pulsed magnetic field are simulated.The calculation results show that the largest electromagnetic force in the melt appears near the solid-liquid interface,and the electromagnetic force is distributed in a gradient.There are intensive electromagnetic vibrations in front of the solid-liquid interface.The forced melt convection is mainly concentrated in front of the solid-liquid interface,accompanied by a larger flow velocity.The simulation results indicate that the grain refinement is attributed to that the electromagnetic vibration and forced convection increase the nucleation rate and the probability of dendrite fragments survival,for making dendrite easily fragmented,homogenizing the melt temperature,and increasing the undercooling in front of the solid-liquid interface.
