| 摘要 |
The present invention concerns an open cell foam ceramic material of high mechanical resistance for porous burners, in which the outer and inner walls of the bridges of hollow triangular cross-section, which form the structure of the foam material, are covered with a thin film of silicon carbide. The film entirely fills the fissures between the internal convex walls of the cavities of the bridges, and corresponding to them forms a rounded-off connecting zone between two neighbouring walls. These rounded-off connecting zones prevent formation of deep fissures (cracks or notches) in the bridges and decisively reinforce the foam ceramic material produced according to the inventive method. <??>The method of producing comprises three new phases of processing, in comparison to the state of the art, which are: Covering of the bridges with a polymer of low viscosity and polymerising it at low temperature; Pyrolysis for transforming the coating polymer into a thin porous carbon film; A thermal treatment at high temperature for infiltrating the foam ceramic material with metallic silica and transforming the porous carbon film into a silicon carbide film. |
