| abstract |
A method for preparing silicon nitride monolith porous ceramics with high toughness and high temperature resistance, α-Si 3 N 4 is used as raw material, Y 2 O 3 is used as auxiliary agent, and β-Si with high aspect ratio is prepared by normal pressure sintering method 3 N 4 whiskers, the prepared β-Si 3 N 4 whiskers are used to configure the casting slurry, and the silicon nitride whiskers are oriented and arranged by tape casting to make thin films and laminated samples, and the vapor phase is evaporated at high temperature through SiO Residual carbon infiltrating and reacting between fibers obtains silicon nitride, and prepares silicon nitride monolithic porous ceramic materials; the invention proposes a structure design idea of fiber orientation arrangement and secondary silicon nitride bonding, and realizes pure nitriding Porous ceramics constructed of silicon fibers are effectively prepared, and the advantages of anisotropy are exerted through directional arrangement, thereby effectively improving the fracture toughness of silicon nitride ceramics, and greatly improving the high temperature resistance through the bonding of pure silicon nitride, which greatly expands the Application range of porous silicon nitride ceramic materials. |