Abstract
The present study aims to determine controlled crystallisation heat treatments and thermal stability for pure B phase glass-ceramic in the Y-Si-Al-O-N system. Experiments using differential thermal analysis and the ultrasonic techniques were performed on a YSiAlON glass to define the optimum nucleation temperature of B phase according to Marotta's method. Changes in elastic properties allowed to determine the optimum nucleation time and to follow the glass to glass-ceramic transformation on massive glass samples. Maximum bulk nucleation occurs after one hour in the range 960-970°C and the grain growth ends after 10 hours at the crystallisation temperature of 1050°C. XRD analyses confirm B phase as the unique crystalline phase thermally stable up to 1150°C and SEM observations show a very fine and homogeneous microstructure with a high crystal volume fraction. By determining optimum conditions for nucleation and crystal growth of B phase, good quality nitrogen glass-ceramics have been produced.
| Original language | English |
|---|---|
| Pages (from-to) | 814-817 |
| Number of pages | 4 |
| Journal | Key Engineering Materials |
| Issue number | 136 PART 2 |
| Publication status | Published - 1997 |
Keywords
- Crystallisation
- Elastic properties
- Glass-ceramic
- Nucleation
- Oxynitride glass