410 vs 420F Stainless Steel: Martensitic Workhorses

 

How do their compositions differ?​

410 has 11.5-13.5% chromium and 0.15% max carbon. 420F contains 12-14% chromium, 0.25-0.4% carbon, and sulfur for machinability, with a small molybdenum addition.​

 

Which offers better hardness and wear resistance?​

420F reaches 50-55 HRC after heat treatment, harder than 410's 40-45 HRC. This makes 420F more wear-resistant, while 410 balances strength with better toughness.​

 

How do they compare in corrosion resistance?​

Both offer moderate corrosion resistance in dry environments, with 420F having a slight edge due to higher chromium. They can rust in moist or salty conditions, requiring protection in harsh settings.​

 

What about their fabrication properties?​

420F is easier to machine than 410, thanks to sulfur, making it ideal for precision parts. 410 is more formable in its annealed state, suitable for simple bending and shaping.​

 

Where are 410 and 420F commonly used?​

410 is used in valve parts, pump shafts, and automotive components. 420F finds applications in knife blades, bearings, and precision machined parts needing good machinability and hardness.