309 vs 310 Stainless Steel: High-Temperature Heavyweights

 

How do their chemical compositions differ?​

309 contains 22-24% chromium, 12-15% nickel, and 0.20% max carbon. 310 has higher chromium (24-26%) and nickel (19-22%), with 0.20% max carbon, enhancing its high-temperature oxidation resistance.​

 

Which performs better at extreme temperatures?​

310 thrives in continuous use up to 1150°C, outperforming 309, which is suitable up to 1040°C. 310 resists scaling and oxidation better in extreme heat, making it ideal for furnace linings and kiln components.​

 

How do they compare in corrosion resistance?​

Both offer good resistance to oxidation and carburization at high temperatures. 310 has better resistance to sulfidation and high-temperature corrosion, while 309 performs adequately in less severe heat environments.​

 

What about their fabrication and welding properties?​

Both are weldable with standard techniques, though 310 may require more care to avoid grain growth. 309 has slightly better formability, but both work-harden moderately and may need annealing for complex cold working.​

 

Where are 309 and 310 commonly used?​

309 is used in furnace parts, heat exchangers, and kiln linings operating at moderate high temperatures. 310 finds applications in incinerators, boiler components, and chemical processing equipment exposed to extreme heat.