A magnetic field was used to directional solidification of dendritic Al-Cu alloys. The primary arm spacing of the dendrites is increased with increasing the external magnetic field strength. This microstructural coars...A magnetic field was used to directional solidification of dendritic Al-Cu alloys. The primary arm spacing of the dendrites is increased with increasing the external magnetic field strength. This microstructural coarsening is related to the thermoelectric current on the l/s interface, which is induced by difference of temperature on the inter- face. Within a magnetic field Lorentz force may be generated in front of the interface, causing a thermoelectric-magneto convection that makes the microstructure coarsened. This induced convection also leads to structural instability so that the secondary arms are well developed when grown in the external field.展开更多
基金Supported by LTU Foundations of Science and Technology
文摘A magnetic field was used to directional solidification of dendritic Al-Cu alloys. The primary arm spacing of the dendrites is increased with increasing the external magnetic field strength. This microstructural coarsening is related to the thermoelectric current on the l/s interface, which is induced by difference of temperature on the inter- face. Within a magnetic field Lorentz force may be generated in front of the interface, causing a thermoelectric-magneto convection that makes the microstructure coarsened. This induced convection also leads to structural instability so that the secondary arms are well developed when grown in the external field.
