Abstract
It is shown through the use of tin crystal that the actual growth rate in the Bridgman growth process could be investigated by recording the temperature-time curves at given axial locations in the melt-solid system. Variations of the growth rate in the seeded and unseeded growth processes of tin crystal have been examined and discussed. The results are summarized as follows.
It is surmised for the seeded growth that the actual growth rate increased with the progress of solidification, and the average rate was 1.7 times the translation rate of the furnace. The increase of the growth rate may be related to the increase in solidified fraction of the melt. In the case of the unseeded growth, the initial growth rate was ten to forty times the translation rate of the furnace but rapidly decreased to about four times that with the progress of solidification. Thus, it is thought that the growth in initial stage proceeds at a high speed independently of the translation rate of the furnace, resulting in a high growth rate compared to the seeded process.
