S32100 Stainless Steel

S32100 is a titanium-stabilized austenitic stainless steel (UNS S32100), corresponding to SUS321. With 17-19% Cr, 9-12% Ni, and 0.15-0.40% Ti, it prevents intergranular corrosion at 400-900°C, suitable for high-temperature welded structures like aircraft exhausts and heat exchangers.

Chemical Composition (wt%): C ≤0.08, Si ≤1.00, Mn ≤2.00, P ≤0.045, S ≤0.030, Cr=17.00-19.00, Ni=9.00-12.00, Ti=0.15-0.40, Fe=Balance

Mechanical Properties (Annealed): Tensile Strength ≥515MPa, Yield Strength ≥205MPa, Elongation ≥40%, Hardness (HB) ≤217

Performance Advantages: Titanium stabilization avoids high-temp intergranular corrosion; good high-temp strength up to 870°C; excellent low-temperature toughness; non-magnetic after annealing.

Equivalent Grades: ASTM A240 321, EN 1.4541, SUS321

Applications: Aircraft exhaust systems, high-temperature heat exchangers, boiler superheaters, chemical reactor tubes, cryogenic equipment.

FAQ

1. Q: How does S32100 differ from S30400? A: S32100 adds titanium (0.15-0.40%) to bind carbon, preventing chromium carbide precipitation at 400-900°C. S30400 (304) lacks titanium, so welded S30400 suffers intergranular corrosion in high-temp service. For aircraft exhausts (600-800°C welded parts), S32100 lasts 10x longer than S30400, justifying its higher cost.

2. Q: Why is S32100 used in cryogenic equipment? A: Its titanium-stabilized austenitic structure retains high toughness at -196°C (liquid nitrogen temp), avoiding cold brittleness. S30400 also works at low temps, but S32100's weld zone toughness is better-critical for cryogenic storage tanks with welded seams. It meets cryogenic safety standards, reducing leakage risks.

3. Q: What's the maximum operating temperature of S32100? A: Continuous service up to 870°C; short-term up to 925°C. Above 870°C, titanium carbide dissolves, reducing corrosion resistance. For temps above 870°C, use S31008 or S30908. S32100 is ideal for 400-870°C welded parts (e.g., boiler superheaters), balancing high-temp performance and weldability.

4. Q: Can S32100 be used in chemical processing? A: Yes, for 400-800°C chemical reactors handling mild acids (dilute sulfuric, organic acids). Titanium stabilization ensures corrosion resistance in welded joints, and its austenitic structure resists chemical attack. It's not suitable for high-chloride environments-use S31635 (316Ti) instead. For non-chloride high-temp chemicals, it's cost-effective vs molybdenum-containing grades.

5. Q: What welding filler is best for S32100? A: Use ER321 filler to maintain titanium content. ER308 filler (no Ti) will cause intergranular corrosion in the weld zone. Weld with TIG at 90-130A; avoid overheating to prevent Ti burnout. No post-weld annealing is needed, simplifying fabrication of heat exchanger tubes with multiple welds.