Abstract: A composite rigid foam structure that has a skin or coating on at least one of its surfaces. The skin is formed in situ by thermal spray techniques. The skin is bonded substantially throughout the surface of the porous substrate to the peripheries of the pores. The skin on the average does not penetrate the surface of the substrate by more than the depth of about 2 to 5 pores. Thus, thermal spraying the skin onto the rigid foam produces a composite that is tightly and uniformly bonded together without unduly increasing the weight of the composite structure. Both thermal conductivity and bonding are excellent.

Abstract: A muzzle flash and blast suppressor comprising a body of reticulated refractory foam generally surrounding the projectile path adjacent the muzzle of a device. One side of the body of foam is exposed to the pressure within the projectile path just behind the projectile, and the other side is exposed to the unconfined ambient pressure. The foam is required to be possessed of sufficient structural strength to permit its exterior side to be exposed without confinement to the ambient environment. Hot exhaust gasses flowing laterally of the projectile path pass through the body from the high to the low pressure side. In such passage the gasses are cooled by expansion and by contact with the interstices of the body. Debris is filtered out and the pressure is substantially reduced. Typically, the refractory foam has from approximately 30 to 100 pores per inch and is from approximately 90 to 50 percent void volume.

Abstract: A refractory composite structure is formed which comprises a ductile refractory metallic layer with a roughened surface which is tightly bonded to a refractory composite structural shell. The roughened surface is preferably dendritic in form and produced by chemical vapor deposition techniques. The refractory composite structural shell is preferably a carbon-carbon composite formed by applying a carbon filament preform to the roughened surface, infiltrating the preform with a carbon matrix precursor, and carbonizing the precursor.

Abstract: A refractory composite structure comprising a ductile refractory metallic layer with a roughened surface which is tightly bonded to a refractory composite structural shell. The roughened surface is dendritic in form and is produced by chemical vapor deposition techniques.

Abstract: An airbag assembly including an inflatable airbag, an ignitable propellant charge for generating inflating gas and a filter between the interior of the airbag and the propellant charge. The filter comprising a porous carbon foam substrate coated substantially throughout with a thermally and structurally stable material which has been formed in situ by chemical vapor deposition techniques.

Abstract: A high temperature resistant structure which is capable of withstanding temperatures well in excess of 2500 degrees Fahrenheit in oxidizing environments for periods of at least several hours. A high temperature resistant substrate such as carbon carbon composite is coated in situ with very thin alternate layers of silicon carbide and a carbide formed from hafnium or zirconium. The coating is preferably formed using chemical vapor deposition procedures.

Abstract: A high temperature resistant reticulated porous foam structure for use as a diesel emission particulate trap. A reticulated porous foam substrate which is capable of maintaining its structural integrity at temperatures in excess of approximately 2500, and preferably 2700, degrees Fahrenheit is coated with a formed in situ oxidation resistant coating which extends substantially throughout the interstices of the porous foam structure. The coating comprises very thin alternate layers of silicon carbide and a carbide formed from a Group IVA metal which has a melting point in excess of approximately 1850 degrees Centigrade.

Abstract: A structure which is resistant to corrosion at high temperatures comprises a ductile layer of a platinum group metal, such as iridium, and a layer of a refractory metal having a high strength at high temperatures, such as rhenium. A solid solution of the two metals is present between and metallurgically bonded to the two metal layers. Further, the structure may include a layer of ceramic such as zirconia or hafnia on the exposed face of the platinum group metal layer.