446 vs 430 Stainless Steel: High-Chromium Ferritic Showdown

 

How do their chemical compositions differ?​

446 contains 23-27% chromium, 0.20% max carbon, and no nickel, with small amounts of manganese and silicon. 430 has 16-18% chromium, 0.12% max carbon, and no nickel. The extra chromium in 446 enhances its oxidation resistance at high temperatures.​

 

Which offers better high-temperature performance?​

446 far outperforms 430 in high-heat environments, withstanding continuous use up to 1800°F (982°C) and intermittent use up to 2000°F (1093°C). 430 tops out around 1400°F (760°C), making 446 ideal for furnace parts and heat-treating equipment.​

 

How do they compare in corrosion resistance?​

446 resists oxidation and sulfidation better at high temperatures, while 430 offers better general corrosion resistance in mild, room-temperature environments. 430 handles moist air and mild chemicals well, but 446 struggles more in aqueous settings despite its high chromium.​

 

What about their fabrication and weldability?​

Both have limited formability, but 430 is more malleable for simple bending and stamping. 446 is harder to weld due to its high chromium, requiring preheating and post-weld annealing to avoid brittleness. 430 welds more easily with standard techniques.​

 

Where are 446 and 430 commonly used?​

446 is used in furnace linings, burner parts, and high-temperature industrial ovens. 430 finds applications in appliance trim, automotive accents, and architectural components where cost and moderate corrosion resistance matter more.