410 vs 430F Stainless Steel: Martensitic vs Ferritic Free-Machining

 

How do their chemical compositions differ?​

410 contains 11.5-13.5% chromium, 0.15% max carbon, and sulfur for machinability. 430F has 16-18% chromium, 0.12% max carbon, sulfur, and no nickel, with a ferritic structure that limits heat treatability.​

 

Which offers better hardness and strength?​

410, when heat-treated, achieves 40-45 HRC and tensile strength up to 700 MPa, outperforming 430F's 18-23 HRC (annealed) and 450-550 MPa. 430F prioritizes machinability over high strength.​

 

How do they compare in corrosion resistance?​

430F offers better corrosion resistance in mild environments due to higher chromium, resisting rust in dry settings. 410 performs adequately in dry conditions but may corrode faster in moisture compared to 430F.​

 

What about their machining and fabrication?​

430F is slightly easier to machine than 410, with sulfur improving chip flow for simple parts. 410 is more formable in annealed state but requires heat treatment to achieve full strength, unlike 430F.​

 

Where are 410 and 430F commonly used?​

410 is in valve parts, pump shafts, and automotive components needing heat-treatable strength. 430F finds use in low-cost machined parts like fasteners and appliance components.