| 摘要 |
PURPOSE:To improve properties of the material as a high-temp. structural material by forming alpha-sialon layer between an Si3N4 ceramic layer and a beta- sialon ceramic layer. CONSTITUTION:Powders of Si3N4, Al2O3 and AlN are mixed to obtain Si5Al1O1 N7 compsn. or the like to prepare the source powder of beta-sialon. On the other hand, an Si3N4-base powder is prepared by adding and mixing about 5wt.% Y2O5 and about 4theta Al2O3 to an Si3N4 powder. Then the beta-sialon source powder and Si3N4-base powder are successively supplied in a press-molding die and pressed to obtain a two-layer molded body consisting of beta-sialon and Si3N4. Then, this molded body is sintered at abut 1800 deg.C for 2 hours in an N2 atmosphere and further treated by heating to form an alpha-sialon layer of 5-1000mum thickness between the Si3N4 ceramic layer and beta-sialon ceramic layer. Thus, the ceramic composite material is produced. |
