Abstract
Nitrogen rich neodymium-ytterbium containing multi-cation α-sialon starting compositions have been prepared by gas pressure sintering using "conventional" α-Si3N4 or plasma produced β-Si3N4 powder. The effect of α-SiAlON nucleation on growth mechanism was investigated by applying different sintering cycles. X-ray diffraction studies of these compositions after sintering revealed that α-sialon was observed as a matrix phase. Microstructural characterisation of the sintered materials by using α-Si3N4 powder as starting composition resulted in a typical equiaxed grain morphology, as expected if the α-SiAlON nucleation step is missed out prior to growth. However, elongated α-SiAlON grains were observed by applying nucleation. In the case of β-Si3N4 containing starting composition, in all cases α-SiAlON grain morphology was observed. The effects of starting Si3N4 powders and different sintering conditions were discussed in detail.
| Original language | English |
|---|---|
| Pages (from-to) | 31-36 |
| Number of pages | 6 |
| Journal | Materials Science Forum |
| Volume | 383 |
| Publication status | Published - 2002 |
| Externally published | Yes |
| Event | 3rd International Symposium on Nitrides - Sevilla, Spain Duration: 5 Jul 2000 → 7 Jul 2000 |
Keywords
- Grain Morphology
- Nucleation
- SiN Starting Powder
- Sintering Conditions
- α-SiAlON