Patent ID: 9404400
Filing Date: 2016-08-02
CPC Classification: F01L,F02B,F02F,F05C

Claim Text:
1. Cylinder head made of cast iron, comprising: a combustion chamber; a valve seat provided in the combustion chamber, said valve seat comprising: an annular bore provided in the cast-iron material; a nickel-based intermediate layer which is provided in said bore; and a contact layer which is provided on said intermediate layer, said contact layer comprising an air-hardening tool steel, wherein said layers are provided in such a manner that an annularly acting compressive stress is present near the free surface of said contact layer; wherein the valve seat is provided by deposition of the nickel-based intermediate layer and the contact layer by welding, and wherein the intermediate layer at an end thereof directed towards the combustion chamber is exposed by flattening of the cylinder head after application of the intermediate and contact layers.