SURFACE DIFFUSIVITY UNDER HIGH-PRESSURE GAS

The sintering behavior of TiO2 under high-pressure gas (100 MPa) was s tudied with respect to densification rate, decreasing rate of specific surface area, and narrowing rate of pore size distribution. At the lo w sintering temperature (800 degrees C) used in this study, the densif ication rate under high-pressure gas was similar to that under low (i. e., 1 atm) pressure. The specific surface area decreased and the pore size distribution narrowed at a faster rate Binder high-pressure gas t han under low-pressure gas. These results imply that high-pressure gas enhances surface diffusion.