Improvement of plasma-sprayed ceramic coating properties by heat-treatment with liquid Mn

Book · Sat Dec 31 04:00:00 EST 1994

OSTI ID:160500

Ohmori, A; Zhou, Z; Inoue, K ^[1]

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1. Osaka Univ. (Japan). Welding Research Inst.

The penetration phenomena of liquid Mn into porous AlO{sub 3} and ZrO{sub 2} (8wt%Y{sub 2}O{sub 3}) coatings, plasma-sprayed on SS400 steel substrate was studied by heating at 1,573 K in a vacuum atmosphere, and the possibility of improving the mechanical properties of the Al{sub 2}O{sub 3} and ZrO{sub 2} coatings by heat-treatment with liquid Mn was examined. It was found that liquid Mn rapidly penetrated the ceramics coatings to the interface between the coating and the substrate. The densification of the coating occurred when Al{sub 2}O{sub 3} and ZrO{sub 2} particles were sintered with liquid Mn that penetrated the porous Al{sub 2}O{sub 3} and ZrO{sub 2} coatings. For Al{sub 2}O{sub 3} coating, the formation of MnAl{sub 2}O{sub 4} was clearly recognized in the connected porosities of Al{sub 2}O{sub 3} coatings penetrated with liquid Mn. In the case of ZrO{sub 2} coating, a dense coating was obtained by the sintered reaction between deposited ZrO{sub 2} particles and the liquid Mn penetrated in the porosities of ZrO{sub 2} coating. The mechanical properties such as the hardness and the fracture stress of both Al{sub 2}O{sub 3} and ZrO{sub 2} coatings heat-treated with liquid Mn were improved greatly, compared with as-sprayed coatings. Moreover, the modulus of elasticity and the fracture toughness of ZrO{sub 2} coating reached the same levels as those of sintered PSZ(Y{sub 2}O{sub 3}).

• OSTI ID: 160500
• Report Number(s): CONF-940684--; ISBN 0-87170-509-5
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
CHEMICAL ANALYSIS
COMPOSITE MATERIALS
EXPERIMENTAL DATA
FRACTURE PROPERTIES
HARDNESS
IMPREGNATION
LIQUID METALS
MANGANESE
MECHANICAL PROPERTIES
MICROSTRUCTURE
PLASMA ARC SPRAYING
POROSITY
SCANNING ELECTRON MICROSCOPY
STEELS
X-RAY DIFFRACTION
YTTRIUM OXIDES
ZIRCONIUM OXIDES