Abstract: The present invention provides a corrosion loss measuring apparatus which enables to quantitatively determine corrosion loss characteristics of ceramic materials and heat-resistant metallic materials, which is excellent in terms of safety, cost, and operation easiness, and whose size can be reduced. The invention also provides a method for measuring corrosion loss by use of the apparatus.

Abstract: A corrosion-resistant silicon nitride ceramics in which an adhesion enhancing layer (3), a stress relaxing layer (4) and a crack extension preventing layer (5) are laminated in this order on a ceramic substrate (2) composed mainly of silicon nitride, and a surface corrosion-resistant layer (6) composed mainly of zirconium oxide stabilized by an element of the group 3a of the periodic table is laminated. The thermal expansion coefficient (?0) of the ceramic substrate (2), the thermal expansion coefficient(?1) of the adhesion enhancing layer (3), and the thermal expansion coefficient (?2) of the stress relaxing layer (4), the thermal expansion coefficient (?3) of the crack extension preventing layer (5), and the thermal expansion coefficient (?4) of the surface corrosion-resistant layer (6) satisfy the following relational expressions (I) to (III): ?0??1??(I) ?3<?2??(II) ?3<?4??(III).

Abstract: An environmental barrier coating material comprising one or more constituents selected from a group consisting of hafnia; hafnia stabilized by one or more rare-earth oxides and/or silica; zirconia-containing hafnia; and zirconia-containing hafnia stabilized by one or more rare-earth oxides and/or silica, which when formed as a coating structure for covering a substrate which has a low thermal expansion coefficient, has hafnon (HfSiO4) serving as a first layer directly formed on the substrate, and hafnia with which the first layer is coated as a second layer.

Abstract: A corrosion-resistant silicon nitride ceramics in which an adhesion enhancing layer (3), a stress relaxing layer (4) and a crack extension preventing layer (5) are laminated in this order on a ceramic substrate (2) composed mainly of silicon nitride, and a surface corrosion-resistant layer (6) composed mainly of zirconium oxide stabilized by an element of the group 3a of the periodic table is laminated.

Abstract: The present invention provides a corrosion loss measuring apparatus which enables to quantitatively determine corrosion loss characteristics of ceramic materials and heat-resistant metallic materials, which is excellent in terms of safety, cost, and operation easiness, and whose size can be reduced. The invention also provides a method for measuring corrosion loss by use of the apparatus.

Abstract: An environmental barrier coating material comprising one or more constituents selected from a group consisting of hafnia; hafnia stabilized by one or more rare-earth oxides and/or silica; zirconia-containing hafnia; and zirconia-containing hafnia stabilized by one or more rare-earth oxides and/or silica, which when formed as a coating structure for covering a substrate which has a low thermal expansion coefficient, has hafnon (HfSiO4) serving as a first layer directly formed on the substrate, and hafnia with which the first layer is coated as a second layer.

Abstract: Anti-corrosion ceramics comprising a substrate of at least one kind of silicon-containing ceramics selected from a silicon nitride, a silicon carbide and Sialon, and a surface protection layer formed on the surface of the substrate, wherein the surface protection layer comprises a zirconium oxide stabilized with an element of the Group IIIa of periodic table, and the total amount of Al and Si in the surface protection layer is suppressed to be not larger than 1% by mass. Particularly, the surface layer has a thickness of from 5 to 200 &mgr;m and a porosity of 5 to 30%. The anti-corrosion ceramics exhibits a high resistance against the corrosion due to the water vapor of high temperatures in a region of not lower than 1000° C., and can be preferably used as parts of internal combustion engines such as parts of gas turbine engines, like a turbine rotor, nozzles, a combustor liner and a transition duct.

Abstract: Anti-corrosion ceramics comprising a substrate of at least one kind of silicon-containing ceramics selected from a silicon nitride, a silicon carbide and Sialon, and a surface protection layer formed on the surface of the substrate, wherein the surface protection layer comprises a zirconium oxide stabilized with an element of the Group IIIa of periodic table, and the total amount of Al and Si in the surface protection layer is suppressed to be not larger than 1% by mass. Particularly, the surface layer has a thickness of from 5 to 200 &mgr;m and a porosity of 5 to 30%. The anti-corrosion ceramics exhibits a high resistance against the corrosion due to the water vapor of high temperatures in a region of not lower than 1000° C., and can be preferably used as parts of internal combustion engines such as parts of gas turbine engines, like a turbine rotor, nozzles, a combustor liner and a transition duct.