With better strength at higher temperatures, Type 422 (S42200) is an appealing alternative to Type 403. Type 422 is a hardenable martensitic stainless steel which is being widely used for high temperatures up to 1200°F. It is capable of being heat treated to various high strength levels. It is often used in aircraft and power industries who require high strength/weight ratios from room temperature to 1200°F.
Steam and gas turbine components
High heat components
UNS: ASTM/ASTE 42200
Adaptable to applications where maximum resistance to corrosion is not required.
Resistant to the corrosive action of the atmosphere, fresh water, steam, and a variety of the milder acids and alkalies.
Good resistance to destructive scaling or oxidation
Continuous service at temperatures up to 1250F.
Temperature will vary with the type of atmosphere, type of construction, and cycle of operation.
Comparable to 18-8 but easier to machine
Help avoid galling with sharply ground tools
Maintain consistent speed and feed
Turning tools: 8-14° side rake
Drilling: 140° point
Threading: grind tools with 10-15° back rake
Cobalt high-speed tools: turn at 90-120 sfpm, drill at 40-75 sfpm, mill at 70-120 sfpm, ream at 20-60 sfpm, roughing and finishing at 200-400 sfpm
Initial forging and rolling at 2100° to 2150°F (1149° to 1177°C)