Combustion chamber with high fire solid layer on the inner walls with oxidation catalyst properties and method for applying this layer

摘要

The internal walls, valves and head surfaces of pistons in internal combustion engines are coated with a ceramic catalytic crystalline coating formed by flame spraying a particulate mixture of 30 to substantially 100% (by weight) cerium oxide, 0,01-20% each of neodymium and praesodymium oxides and as optional ingredients one or more of aluminium, lanthanum, scandium, yttrium, thorium, niobium, tantalum and vanadium oxides. Aluminium may be added to the mixture to increase thermal conductivity of the coating; chromium or tungsten carbides may be added to resist abrasion. In practice the compositions may contain also phosphate, sulphate, lime, magnesia, silica and iron oxide as minor ingredients.