Ceramic bodies comprising nanofibres
Introduction
The invention concerns a process for the production of a ceramic body comprising nanofibres of silicon nitride or silicon carbide bonded together to form a single body. The process comprises three steps: impregnation of a polyurethane foam with a preceramic polymer, cross-linking of the precursor, pyrolysis of the impregnated polyurethane foam.

Technical features
The invention concerns a process for the production of a ceramic body comprising nanofibres of silicon nitride or silicon carbide bonded together to form a single body. The process comprises the following three steps: impregnation of an open-cell polyurethane foam with a preceramic polymer containing silicon, oxygen, carbon and hydrogen; cross-linking of the precursor; pyrolysis of the impregnated foam at a temperature ranging between 1400 and 1500°C in a controlled atmosphere of nitrogen or an inert gas. The invention concerns also the ceramic bodies obtained according to the process of the invention.
Possible Applications
- Thermal insulation for low and high temperatures;
- High temperature applications;
- Reinforcement for composite materials;
- Support for catalysts;
- Thermal insulation for applications in construction, industry, clothing;
- Filtration of liquids or gases.
Advantages
- High level of thermal insulation;
- Possibility to produce silicon nitride or silicon carbide felts in a controlled form;
- Very high thermal and chemical resistance.