Abstract: A foam barrier heat shield is provided having a layer of foam adhesively disposed between opposing first and second metallic outer layers. The foam is expanded in between the outer layers and is adhesively formed to the outer layers without the use of a separate adhesive. In addition to shielding heat, the heat shield is effective as a noise barrier and is internally damped against vibration. In a preferred embodiment, the foam is a substantially rigid polyurethane foam that is sufficiently pliant to be bent to and accommodate a particular shape and contour to which the heat shield will conform in use, and it is reversibly deformable acoustical deflections.

Abstract: An exhaust manifold (10, 110) is provided having a ceramic inner layer (22, 32) defining an exhaust gas passageway (20), and a composite insulation zone (24, 26) that is highly thermally insulating. In one embodiment, the composite insulation zone (24) includes a plurality of metallic foils (31, 32) in alternating arrangement with layers having insulating qualities. In the composite insulation zone, the layers having insulating qualities can include ceramic layers (26), evacuated spaces, microsphere layers (37) including substantially evacuated microspheres, or a combination of these. A novel sealing arrangement also is provided for sealing the ceramic inner and metallic outer layers of a metal-encased-ceramic exhaust manifold at a location adjacent the inlet port (14, 15, 16) of a runner of the manifold. A sealing gasket (140) is substantially completely encased within or shielded by the metallic outer layer, so as not to contact the cylinder head (115) when assembled to an internal combustion engine.

Abstract: A foam barrier heat shield is provided having a layer of foam adhesively disposed between opposing first and second metallic outer layers. The foam is expanded in between the outer layers and is adhesively formed to the outer layers without the use of a separate adhesive. In addition to shielding heat, the heat shield is effective as a noise barrier and is internally damped against vibration. In a preferred embodiment, the foam is a substantially rigid polyurethane foam that is sufficiently pliant to be bent to and accommodate a particular shape and contour to which the heat shield will conform in use, and it is reversibly deformable acoustical deflections.

Abstract: An exhaust manifold is provided having ceramic inner layer that is highly resistant to cracking from thermal cycling. In a preferred embodiment, the ceramic inner layer is slip cast from a slip composition having a major amount of fused silica which has an amorphous structure. The manifold also has a ceramic insulation layer, a strain isolation layer and an outer structural layer in various embodiments. According to one embodiment, the strain isolation layer is provided in the form of an intumescent mat that expands on heating and contracts on cooling up to a certain crossover temperature, above which it loses the ability to contract on cooling. In a preferred embodiment, a catalyst-coated support body is provided in the exhaust manifold. As exhaust gases pass through the manifold, noxious components of the exhaust gases begin to convert to environmentally benign species via the catalyst prior to reaching the catalytic converter. Methods of making an exhaust manifold also are provided.