Saburo Sano

Cake growth control in slip casting

A control technique of cake growth in slip casting was studied. The influence of geometrical features of the gypsum mold upon the cake growth pattern was examined in experimental slip casting using T-shaped gypsum molds. The T-shaped molds were of two types; one had walls inside and the other did not. These walls were formed from silicone rubber and did not transmit water. A water flow in the gypsum mold was controlled by silicone rubber walls, so that cake growth was controlled. Cake growth during slip casting using T-shaped mold was predicted by computer simulation.

Observation of the Microwave Effect On the Diffusion Behavior in 28 GHz Millimeter-Wave Sintered Alumina

Microwave effect on diffusion behavior was investigated by examining the relation between the enhanced densification of the 28 GHz millimeter-wave-sintered alumina and the change of optical absorption peak of doped Cr ions. Among two optical absorption peaks due to Cr ions, the peak I due to the A2→E electronic transition clearly showed a different dependence on the relative density for both millimeter-waveand conventionally sintered aluminas, respectively. For the millimeter-wave-sintered alumina, a large shift of the peak I was observed against a slight change of the relative density from 80%TD (theoretical density) to 90%TD. For the conventionally-sintered alumina, only a sight shift of the peak I was observed irrespective of a large change of the relative density from 68%TD to 90%TD. Assuming that the same diffusion stage of Cr ions in alumina can be detected by observing the peak I at the same wavelength, the enhanced densification is estimated to be about 18%TD in millimeter-wave-sintered alumina.