Abstract
Electrically insulating alumina films were fabricated on steel substrates using supersonic aerosol deposition and their hardness and scratchability were measured. Alumina particles (0.4-μm diameter) were supersonically sprayed inside a low-pressure chamber using between 1 and 20 nozzle passes. These alumina particles were annealed between 300 and 800 K to determine the temperature’s effect on film crystal size (37-41 nm). Smoother surface morphology and increased electrical resistance of the thin films were observed as their thicknesses grew by increasing the number of passes. Resistances of up to 10,000 MΩ demonstrate robust electrical insulation. Significant hardness was measured (1232 hv or 13.33 GPa), but the alumina films could be peeled off with normal loads of 36 and 47 N for films deposited on stainless steel and SKD11 substrates, respectively. High insulation and hardness confirm that these alumina films would make excellent electrical insulators.
| Original language | English |
|---|---|
| Pages (from-to) | 1046-1051 |
| Number of pages | 6 |
| Journal | Journal of Thermal Spray Technology |
| Volume | 24 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 2015 Aug 6 |
Bibliographical note
Funding Information:This work was supported by the Human Resources Development program (No. 20124030200120) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry and Energy and by NRF-2013R1A2A2A05005589. The authors extend their appreciation to the Deanship of Scientific Research at King Saud University for its funding this Prolific Research group (PRG-1436-03). The authors are grateful for the financial support made by MS Autotech.
Publisher Copyright:
© 2015, ASM International.
Keywords
- aerosol deposition
- alumina
- electrical insulation
- hardness
- scratchability
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Materials Chemistry