Patent ID: 6959916

Claim:
A valve having a valve disc and a valve body, with a valve seat for at least one of them being formed of a nickel base alloy in which compound particles are dispersed, wherein the nickel base alloy comprises a nickel base alloy in which at least one of silicide particles and boride particles are dispersed in the matrix of a metal microstructure, the valve seat made of the nickel base alloy and at least one of the valve disc and the valve body are diffusion bonded by way of an intermediate layer of a melting point lower than that of them, and the nickel base alloy contains 8% by weight or less of silicon, 0 to 4% by weight of boron, 7 to 30% by weight of chromium, 1.2% or less of carbon, 0 to 5% by weight of tungsten and 42% by weight or less of iron (in a range not exceeding the amount of nickel) in which at least silicide particles are dispersed in the matrix of the metal microstructure.