Influence of electrolyte temperature on properties and infrared emissivity of MAO ceramic coating on 6061 aluminum alloy
| Autor: | Mohannad M.S. Al Bosta, Kung-Jeng Ma |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Materials science
Alloy Infrared spectroscopy Electrolyte engineering.material Condensed Matter Physics Microstructure Cristobalite Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials visual_art Emissivity engineering visual_art.visual_art_medium Ceramic Fourier transform infrared spectroscopy Composite material |
| Zdroj: | Infrared Physics & Technology. 67:63-72 |
| ISSN: | 1350-4495 |
| DOI: | 10.1016/j.infrared.2014.07.009 |
| Popis: | 6061 aluminum alloy was treated by MAO at various temperatures of the alkali silicate electrolyte using pulsed bipolar current mode for ten minutes. The surface microstructures and properties were studied using SEM, EDX, and XRD. The infrared emissivities of the MAO ceramic coatings were measured at the 70 °C using FTIR spectrometer. The electrolyte temperature strongly affected all the surface properties. The MAO alumina ceramics prepared in cold electrolytes have volcano-like and accumulated particles microstructures, while those prepared in hot electrolytes were: rougher, thinner and contained grainy spherical hollow bulgy microstructures with more pore density and more sillimanite and cristobalite phases which enhanced the IR emissivity. Also, the increment of sillimanite and cristobalite phases moved the apparent peaks toward longer wavelengths, and broadened the opaque region of the IR spectra. As a result, the increment of electrolyte temperature from 12.3 °C to 90.5 °C increased the average of LWIR emissivity from 80.4% to 94.4%, respectively, for the MAO ceramic coatings. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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