Insulated exhaust port liner for a cylinder head assembly of a motor vehicle

A cylinder head assembly for an internal combustion engine of a motor vehicle, the cylinder head assembly comprising:

• an insulated exhaust port liner comprising:
• a sealing layer having a first surface defining a passage for fluidly connecting to the internal combustion engine for receiving exhaust gas, and the sealing layer further having a second surface opposite to the first surface;
• and
• a thermal barrier layer formed on the second surface of the sealing layer, with the thermal barrier layer comprising a porous non-woven material;
• and,
• wherein the thermal barrier layer has an inwardly facing surface and an outwardly facing surface, wherein a wall thickness is defined by the inwardly facing surface and the outwardly facing surface, and wherein the inwardly facing surface is attached to the second surface of the sealing layer, and wherein the sealing layer includes at least one flange dividing the thermal barrier layer into separate portions by extending through the wall thickness of the thermal barrier layer;
• and
• a cylinder head cast around the insulated exhaust port liner.

A method of manufacturing a cylinder head assembly having a cylinder head and an exhaust port liner for an internal combustion engine of a motor vehicle, the method comprising:

• forming an insulated exhaust port liner by:
• forming a sealing layer having a first surface to define a passage for fluidly connecting to the internal combustion engine and receiving exhaust gas and a second surface opposite to the first surface;
• forming a thermal barrier layer coated onto the second surface of the sealing layer, with the thermal barrier layer being comprised of a porous non-woven material, and wherein the thermal barrier layer has an inwardly facing surface and an outwardly facing surface, wherein a wall thickness is defined by the inwardly facing surface and the outwardly facing surface, and wherein the inwardly facing surface is attached to the second surface of the sealing layer;
• and
• forming at least one flange in the sealing layer, wherein the at least one flange extends through the wall thickness of the thermal barrier layer thereby dividing the thermal barrier layer into separate portions;
• and
• casting the cylinder head around the insulated exhaust port liner.