简介 |
PROBLEM TO BE SOLVED : To provide a silicon nitride ceramic having a high temperature corrosion resistant coating film and its manufacturing method.SOLUTION : The silicon nitride ceramic has a rare earth titanate as the high temperature corrosion resistant layer on the surface thereof in which a rare earth silicate is contained by volume ratio of 1 : (0-0.7) as a material for forming a multi-phase and has a rare earth silicate as a bonding layer for the silicon nitride ceramic and the high temperature corrosion resistant layer. As a result, the silicon nitride ceramic has excellent high temperature steam corrosion resistance at a high temperature of ≥1, 100°C. The high temperature corrosion resistant layer is durable for a long time even when the film is thin because there is no wear of the coating film due to corrosion and exhibits self-repairing function even if crack is produced on the coating film by accident by giving a rare earth enriched rare earth titanate composition to the coating film. |