New generation of plasma-sprayed mullite coatings on silicon carbide

Journal Article · Tue Feb 28 23:00:00 EST 1995 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1995.tb08236.x· OSTI ID:79784

Lee, K N; Miller, R A; Jacobson, N S ^[1]

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1. NASA-Lewis Research Center, Cleveland, OH (United States)

Mullite is promising as a protective coating for silicon-based aggressive high-temperature environments. Conventionally plasma-sprayed mullite on SiC tends to crack and debond on thermal cycling. It is shown that this behavior is due to the presence of amorphous mullite in the conventionally sprayed mullite. Heating the SiC substrate during the plasma spraying eliminated the amorphous phase and produced coatings with dramatically improved properties. The new coating exhibits excellent adherence and crack resistance under thermal cycling between room temperature and 1,000--1,400C. Preliminary tests showed good resistance to Na{sub 2}CO{sub 3}-induced hot corrosion.

• Sponsoring Organization: USDOE
• OSTI ID: 79784
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 3 Vol. 78; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHEMICAL ANALYSIS
CORROSION PROTECTION
DIFFERENTIAL THERMAL ANALYSIS
DILATOMETRY
LATTICE PARAMETERS
MULLITE
PHASE STUDIES
PLASMA ARC SPRAYING
PROTECTIVE COATINGS
SCANNING ELECTRON MICROSCOPY
SILICON CARBIDES
SODIUM CARBONATES
SURFACE COATING
THERMAL CYCLING
THERMAL EXPANSION
X-RAY DIFFRACTION