Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings
This paper describes the manufacture of a new ceramic coating system based on Al2O3/SiC nanocomposite powder prepared by sol-gel processing followed by low pressure plasma spraying (LPPS) onto stainless steel substrates. In order to produce nanocomposite coatings of good adhesion and low porosity, t...
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| Format: | Conference item |
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2001
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| _version_ | 1797063888419684352 |
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| author | Jiansirisomboon, S Roberts, S Grant, P |
| author_facet | Jiansirisomboon, S Roberts, S Grant, P |
| author_sort | Jiansirisomboon, S |
| collection | OXFORD |
| description | This paper describes the manufacture of a new ceramic coating system based on Al2O3/SiC nanocomposite powder prepared by sol-gel processing followed by low pressure plasma spraying (LPPS) onto stainless steel substrates. In order to produce nanocomposite coatings of good adhesion and low porosity, the substrates were water-cooled to minimise thermal stresses associated with coefficient of thermal expansion mismatch and a CoNiCrAlY bond coat was used. The sol-gel powder feedstock and the as-sprayed coatings have been characterised by a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), and Nuclear Magnetic Resonance (NMR). The coating characteristics were compared with a reference Al2O3 coating prepared from commercial feedstock powder. The thermal exposure of the sol-gel powder during spraying caused phase-changes and phase-decomposition. Examination of the sprayed coatings showed that it was possible to maintain the 20-200 nm SiC particles in the final Al2O3/SiC nanocomposite coating. The coatings also contained both stable alpha-Al2O3 and metastable gamma-Al2O3. Some minority phases such as silica and aluminosilicate formed in the sol-gel feedstock powder were fully decomposed during LPPS. This preliminary study indicates that sol-gel and LPPS processing is a potential route for the manufacture of nanocomposite coatings, which may offer significant improvements in some aspects of coating properties. |
| first_indexed | 2024-03-06T21:06:24Z |
| format | Conference item |
| id | oxford-uuid:3c9d4fda-025c-4db4-acf1-0260025c6f74 |
| institution | University of Oxford |
| last_indexed | 2024-03-06T21:06:24Z |
| publishDate | 2001 |
| record_format | dspace |
| spelling | oxford-uuid:3c9d4fda-025c-4db4-acf1-0260025c6f742022-03-26T14:14:38ZLow pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatingsConference itemhttp://purl.org/coar/resource_type/c_5794uuid:3c9d4fda-025c-4db4-acf1-0260025c6f74Symplectic Elements at Oxford2001Jiansirisomboon, SRoberts, SGrant, PThis paper describes the manufacture of a new ceramic coating system based on Al2O3/SiC nanocomposite powder prepared by sol-gel processing followed by low pressure plasma spraying (LPPS) onto stainless steel substrates. In order to produce nanocomposite coatings of good adhesion and low porosity, the substrates were water-cooled to minimise thermal stresses associated with coefficient of thermal expansion mismatch and a CoNiCrAlY bond coat was used. The sol-gel powder feedstock and the as-sprayed coatings have been characterised by a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), and Nuclear Magnetic Resonance (NMR). The coating characteristics were compared with a reference Al2O3 coating prepared from commercial feedstock powder. The thermal exposure of the sol-gel powder during spraying caused phase-changes and phase-decomposition. Examination of the sprayed coatings showed that it was possible to maintain the 20-200 nm SiC particles in the final Al2O3/SiC nanocomposite coating. The coatings also contained both stable alpha-Al2O3 and metastable gamma-Al2O3. Some minority phases such as silica and aluminosilicate formed in the sol-gel feedstock powder were fully decomposed during LPPS. This preliminary study indicates that sol-gel and LPPS processing is a potential route for the manufacture of nanocomposite coatings, which may offer significant improvements in some aspects of coating properties. |
| spellingShingle | Jiansirisomboon, S Roberts, S Grant, P Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings |
| title | Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings |
| title_full | Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings |
| title_fullStr | Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings |
| title_full_unstemmed | Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings |
| title_short | Low pressure plasma spraying of sol-gel Al2O3/SiC nanocomposite coatings |
| title_sort | low pressure plasma spraying of sol gel al2o3 sic nanocomposite coatings |
| work_keys_str_mv | AT jiansirisomboons lowpressureplasmasprayingofsolgelal2o3sicnanocompositecoatings AT robertss lowpressureplasmasprayingofsolgelal2o3sicnanocompositecoatings AT grantp lowpressureplasmasprayingofsolgelal2o3sicnanocompositecoatings |