COMPOSITE CERAMIC MATERIAL FOR APPLICATION IN ENGINEERING AT HIGH TEMPERATURE AND UNDER SEVERE CONDITION OF THERMAL SHOCK AND ITS PRODUCTION

摘要

PURPOSE: To improve mechanical strength, thermal shock resistance and toughness by adding a dispersant or the like to a specified mixture to prepare a suspension material, adding a plasticizer assistant or the like, mixing and pulverizing, drying, pulverizing and sifting to produce granules. ;CONSTITUTION: A Si₃N₄ matrix, a BN dispersion phase and a specified amt. of TiB₂ are compounded to prepare a mixture, to which a solvent containing a dispersant and a flocculant is added to obtain a suspension having low potential Z and a good dispersion state. Then a sintering additive comprising Y₂O₃₂, Al₂O₃ and ZrSiO₄ is added to the suspension, and mixed and pulverized in a grinder in the presence of a plasticizer assistant and a binder to obtain a completely dispersed suspension material. Then the suspension material is spray-dried to obtain granules, which are pulverized, sifted and formed into pellets to obtain a granulated mixture of granules having ≤250 μm grain size.;COPYRIGHT: (C)1995,JPO