Continuing the former report, the changes of viscosity of molten metals in air were measured by flowing-dow method under different melting conditions. The results obtained were as follows: (1) The difference of max. heating temperature was one of the most effective factors on the viscosity and its effect was indicated as an indented curve of viscosity by increase of max. heating temperature. (2) The effects of holding time at max.heating temperature were very different according to the temperature at which the specimen was held and a close relation was recognized with the heating velocity as the same factor of time. (3) Fast heating for melting showed good results for viscosity in general but under low max.heating temp, fast heating was not always profitable for viscosity. (4) As the total melting time, the best condition of viscosity was found at about 100 min under any combination of holding time and heating velocity. In the range above 100 min, the second best condition was found at about 200 min and the midway temperatures resulted in the worst condition for viscosity. Above 200 min, the viscosity increased.
Please do not copy without permission.