430 stainless steel (ferrite stainless steel)Composition: 16-18% Cr, low carbon (≤0.12% C), nickel free.FeaturesCorrosion resistance: medium, suitable for mild environments (such as atmosphere, fresh water), but less than austenitic stainless steel (such as 304).Magnetic: Has magnetic properties.Wo
430 stainless steel (ferrite stainless steel)
Composition: 16-18% Cr, low carbon (≤0.12% C), nickel free.
Features
Corrosion resistance: medium, suitable for mild environments (such as atmosphere, fresh water), but less than austenitic stainless steel (such as 304).
Magnetic: Has magnetic properties.
Workability: Formability is general, poor welding performance (easy embrittlement).
Heat treatment: cannot be strengthened by heat treatment.
Typical applications
Decorative parts (such as car trim), home appliance parts, tableware, architectural decoration.
Selection suggestion: Suitable for scenarios with limited budget, medium corrosion resistance and no need for high strength.
2.431 stainless steel (Martensitic stainless steel)
Composition: 15-17% Cr, 1.25-2.5% Ni, 0.12-0.22% C.
Features
Strength and hardness: High strength and hardness (HRC 35-45) can be obtained by quenching + tempering.
Corrosion resistance: Better than 420 series, but weaker than austenitic stainless steel.
Magnetic: Has magnetic properties.
Workability: After heat treatment, poor weldability.
Typical applications
High stress parts (such as shafts, pump parts), aviation fasteners, surgical instruments.
Selection suggestion: Suitable for engineering parts requiring high strength, wear resistance and certain corrosion resistance.
420F stainless steel (free cutting martensitic stainless steel)
Composition: 12-14% Cr, high carbon (≥0.15% C), added sulfur (S) or selenium (Se) to improve machinability.
Features
Machinability: Excellent, suitable for high-speed automatic processing.
Corrosion resistance: low (high carbon + low chromium), easy to rust, need surface treatment (such as coating).
Hardness: HRC 50+ can be reached by heat treatment, good wear resistance.
Magnetism: Strong magnetism.
Typical applications
Tools (scalpels, razor blades), measuring tools, threaded parts.
Selection suggestion: Suitable for high cutting efficiency requirements, high hardness but corrosion resistance requirements are not high occasions.
430F stainless steel (free cutting ferritic stainless steel)
Composition: 16-18% Cr, added sulfur (S) or selenium (Se) to improve machinability, low carbon.
Features
Machinability: better than 430, suitable for mass processing.
Corrosion resistance: Similar to 430, but sulfur/selenium addition may slightly reduce corrosion resistance.
Mechanical properties: low strength, can not be strengthened by heat treatment.
Magnetism: Strong magnetism.
Typical applications
Screws, nuts, shafts and other parts that need to be machined frequently.
Selection suggestions: Suitable for general purpose parts requiring easy cutting and medium corrosion resistance to avoid high stress or corrosive environments.