347 stainless steel plate

Q: What is the key chemical composition and grade equivalents of 347 stainless steel plate?

A: 347 (UNS S34700, EN 1.4550) is an austenitic stainless steel with Cr 17.0-19.0%, Ni 9.0-13.0%, Nb+Ta 8×C-1.0% (niobium-tantalum stabilizer), and C ≤ 0.08%. Equivalent grades: JIS SUS347, GB 06Cr18Ni11Nb, DIN X6CrNiNb18-10.

 

Q: What is the core advantage of 347 stainless steel plate over 321?

A: 347 uses niobium (Nb) as the stabilizer (vs. titanium in 321), offering higher high-temperature strength (up to 900°C) and better creep resistance. It also has superior weldability and resists intergranular corrosion (IGC) in extreme thermal cycling.

 

Q: What are the typical mechanical properties and operating temperature range of 347 stainless steel plate?

A: Operating temperature: -270°C to 900°C. Mechanical properties (annealed): Tensile strength ≥ 515 MPa, Yield strength ≥ 205 MPa, Elongation ≥ 40%, Hardness (HB) ≤ 201.

 

Q: What are the main industrial applications of 347 stainless steel plate?

A: Ideal for high-temperature welded equipment: boiler superheaters/reheaters, pressure vessels, chemical reactors, jet engine components, nuclear power plant piping, and exhaust systems in high-temperature environments.

 

Q: When is 347 stainless steel plate preferred over 316L and 304?

A: Choose 347 for high-temperature (≥500°C) welded applications requiring IGC resistance and creep strength. 316L is better for chloride-rich corrosion (e.g., seawater), while 304 is suitable for general-purpose, low-temperature environments with lower corrosion resistance requirements.