Valve Materials
Stainless steels
- Ferritic (401 - inlet valves, 443 -exhaust valves)
- Austenitic (331 - exhaust valves)
- Precipitation hardened austenitic (21-N4)
- Nitron Ti6Al4V in F1
Nickel-based superalloys (Nimonic 80A, 81)
Valve sealing faces are hardfaced (wear more likely than corrosion as they run cooler)
- Co-based for iron alloys (Stellite 6)
- Ni-based for nickel alloys (Deloro 60)