Grade 420 is a high carbon steel with minimum chromium content of 12%. This can be hardened through heat treatment.
This material also comes in a 420 ESR variation.
Specifications:
UNS S42000, X20Cr13, AMS 5506, AMS 5621, ASTM A-276, ASTM A-314, ASTM A-473, ASTM A-580, QQ-S-763, QQ-S-766.
Applications:
shear blades, needle valves, dental and surgical equipment, cutlery,pump shafts, steel balls.