HIGH-RESOLUTION ELECTRON-MICROSCOPY IN-SITU OBSERVATION OF DYNAMIC BEHAVIOR OF GRAIN-BOUNDARIES AND INTERFACES AT VERY HIGH-TEMPERATURES

Two types of specimen-heating holder have been developed that allow on e to observe, at near-atomic resolution, phenomena or reactions taking place at very high temperatures such as 1773K. The performance of the heating holders is described. Some typical examples of results obtain ed using these holders are given. These include formation of SiC throu gh reaction between Si and C, growth of SiC, formation of a void at a grain boundary in SiC during sintering, surface reconstruction of Au d eposited on Si, motion of the solid-liquid interface in Al2O3, and dyn amic instability of a grain boundary in CuGa2.