Abstract
Free standing alumina-3% titania samples were prepared by gas- and water-stabilized plasma (GSP and WSP) spraying. These free standing forms consisted of metastable γ and δ-alumina, as well as α-Al2O3. The microstructures of the materials were similar for both plasma spraying methods and typically exhibit distinct boundaries around splats, columnar grains, and inter- and infra-lamellar porosity. The modulus of rupture (MOR) and porosity were also similar for both GSP- and WSP-sprayed specimens. Four point bend tests with in situ acoustic emission (AE) were used to study the cracking behavior of these materials. Catastrophic failure was observed for GSP-sprayed samples while WSP-samples exhibited microcracking before failure. The amplitude and energy distributions were also investigated and it was thereby determined that the percentage of macrocracks for GSP-sprayed samples is much larger than for WSP-sprayed samples. The processing effects, which induced differences in microstructure, can account for the differences in AE responses.
| Original language | English |
|---|---|
| Pages (from-to) | 108-114 |
| Number of pages | 7 |
| Journal | Thin Solid Films |
| Volume | 310 |
| Issue number | 1-2 |
| Publication status | Published - Nov 21 1997 |
| Externally published | Yes |
Keywords
- Emission responses
- Plasma-sprayed alumina
- Titania deposits
ASJC Scopus subject areas
- Surfaces, Coatings and Films
- Condensed Matter Physics
- Surfaces and Interfaces