Fiber reinforced ceramic matrix composite internal combustion engine exhaust manifold

A method of making a high temperature resistant fiber reinforced ceramic matrix composite exhaust manifold for an engine comprising the steps of:

• a) forming a liner of a cast monolithic ceramic material containing pores;
• b) filling the pores of the cast monolithic ceramic material with a pre-ceramic polymer resin;
• c) coating reinforcing fibers with an interface material to prevent a pre-ceramic polymer resin from adhering directly to the reinforcing fibers, the reinforcing fibers comprising fibers of at least one of alumina, high purity alumina, alumina boro silicate, mullite, alumina silicate, silicon nitride, silicon carbide, HPZ, graphite, carbon, or peat, the interface material comprising a few microns thickness of at least one of carbon, silicon nitride, silicon carbide, silicon carboxide, or boron nitride;
• d) forming a mixture of a pre-ceramic polymer resin chosen from the group consisting of silicon-carboxyl resin, monoaluminum phosphate resin, or alumina silicate resin and the reinforcing fibers coated with the interface material;
• e) forming an exhaust manifold shaped structure from the mixture of the pre-ceramic polymer resin and the reinforcing fibers coated with the interface material by placing the mixture on at least a portion of the cast monolithic ceramic material;
• and,
• f) firing the exhaust manifold shaped structure at a temperature and for a time sufficient to convert the pre-ceramic polymer resin to a ceramic thereby forming a reinforced ceramic composite.

A method of making a high temperature resistant fiber reinforced ceramic matrix composite exhaust manifold for an engine comprising the steps of:

• a) forming a liner of a cast monolithic ceramic material containing pores;
• b) filling the pores of the cast monolithic ceramic material with a pre-ceramic polymer resin;
• c) coating reinforcing fibers with an interface material to prevent a pre-ceramic polymer resin from adhering directly to the reinforcing fibers, the reinforcing fibers comprising fibers of at least one of alumina, high purity alumina, alumina boro silicate, mullite, alumina, silicate, silicon nitride, silicon carbide, HPZ, graphite, carbon, or peat, the interface material comprising 0.1 to 5.0 microns thickness of at least one of carbon, silicon nitride, silicon carbide, silicon carboxide, or boron nitride;
• d) forming a mixture of silicon-carboxyl resin and the reinforcing fibers coated with the interface material;
• e) forming an exhaust manifold shaped structure from the mixture of the silicon-carboxyl resin and the reinforcing fibers coated with the innerface material by placing the mixture on at least a portion of the cast monolithic ceramic material;
• and,
• f) firing the exhaust manifold shaped structure at a temperature and for a time sufficient to convert the silicon-carboxyl to a ceramic.