Patent ID: 9464730
Filing Date: 2016-10-11
CPC Classification: B22F,C22C,C22F,F01L,F16K,Y10T

Claim Text:
1. An exhaust valve spindle for an exhaust valve in an internal combustion engine, which exhaust valve spindle has a shaft and a valve disc at a lower end of the shaft, which valve disc at its upper surface has a seat area, wherein the valve disc is of stainless steel and the seat area is of a nickel-based alloy comprising, stated in percent-by-weight and apart from common impurities and inevitable residual amounts of deoxidizing components, at least from 34.0 to 44.0% Cr, an aggregate amount of Nb and Ta in the range from at least 3.2 to 6.1%, from 0.3 to 2.0% Ti, at the most 0.05% Al, at the most 0.04% B, at the most 0.8% Fe, at the most 0.04% C, at the most 0.4% Si, and a balance of Ni, where the amount of Ti+Nb +0.5×Ta is in the range from 3.4 to 6.6%, and where the amount of Nb+0.5×Ta is less than 3.0% if the amount of Ti is larger than 1.5%.