321 stainless steel is a titanium-stabilized austenitic grade specifically formulated to prevent sensitization and intergranular corrosion in the 425-815°C (800-1500°F) temperature range. Titanium addition (5× carbon minimum) preferentially forms titanium carbides, preventing chromium carbide precipitation during elevated temperature exposure. This alloy offers excellent oxidation resistance, good mechanical properties up to 800°C, and superior weldability for applications requiring resistance to thermal cycling .
1. Product Specifications & Physical DataZYTC Alloy supplies 321 stainless steel in comprehensive mill forms for high-temperature industrial applications requiring verified properties and material traceability. Available Forms: Sheet, strip, plate, bar (round, hex, flat, square), tube, and forging stock . Specifications: ASTM A240, ASTM A276, ASTM A312, EN 10088-2 1.4541 (X6CrNiTi18-10), UNS S32100 .
| Chemical Composition (Weight %) | 321 Stainless Specification |
|---|
| Chromium (Cr) | 17.0 - 19.0 | | Nickel (Ni) | 9.5 - 12.0 | | Titanium (Ti) | 5 × C min - 0.70 max. | | Carbon (C) | 0.08 max. | | Manganese (Mn) | 2.0 max. | | Silicon (Si) | 0.40 - 1.00 | | Phosphorus (P) | 0.040 max. | | Sulfur (S) | 0.030 max. | | Nitrogen (N) | 0.10 max. | | Molybdenum (Mo) | 0.50 max. | | Iron (Fe) | Balance |
| Physical Properties | Metric | Imperial |
|---|
| Density | 7.9 - 8.0 g/cm³ | 0.285 - 0.289 lb/in³ | | Melting Point | 1400 - 1425°C | 2550 - 2600°F | | Modulus of Elasticity | 193 GPa | 28,000 ksi | | Thermal Conductivity (RT) | 16.1 W/m·K | 112 BTU·in/hr·ft²·°F | | Thermal Expansion (20-100°C) | 16.5 µm/m·°C | 9.2 µin/in·°F | | Electrical Resistivity | 0.72 µΩ·m | 0.72 µΩ·m |
| Mechanical Properties (Minimum) | Value | Unit |
|---|
| Proof Strength (0.2% offset) | 205 MPa | 30 ksi | | Tensile Strength | 515 MPa | 75 ksi | | Elongation (in 50mm) | 40% | 40% | | Hardness (Brinell) | 217 max. | 217 max. |
2. Fabrication & Material ComparisonHeat Treatment Options: Solution Annealing: 950-1120°C (1740-2050°F), rapid cool (water quench) Stabilizing Treatment: 870-900°C (1600-1650°F) × 1 hour per 25mm thickness, air cool; recommended for severe service above 425°C Stress Relief: 700°C (1300°F) × 1-2 hours, air cool
Forming: Excellent formability in annealed condition; work-hardening rate similar to 304 . Machining: Similar to 304; requires sharp tools, positive feeds, and adequate coolant to manage work hardening . Welding: Excellent weldability using TIG, MIG, SMAW, and resistance methods; 347 filler (with niobium) commonly used per AS 1554.6; no post-weld annealing required . Material Comparison: vs. 304 Stainless: Titanium stabilization prevents sensitization; preferred for service in 425-815°C range . vs. 316L: Lower molybdenum content; 321 selected specifically for high-temperature applications rather than chloride resistance . vs. 347 Stainless: Niobium-stabilized vs. titanium-stabilized; 321 offers better oxidation resistance; 347 offers better creep strength . vs. 309/310: Lower chromium and nickel; 321 offers good high-temperature performance at lower cost .
3. ApplicationsAutomotive & Aerospace: Exhaust manifolds, exhaust systems, engine components Industrial Furnaces: Furnace parts, heat treatment equipment, heating element tubing Heat Exchangers: Tubing for high-temperature service, expansion joints, bellows Mineral Processing: Woven or welded screens for high-temperature processing Power Generation: Boiler components, superheater supports Petrochemical: Reactor internals, piping for elevated temperature service Construction: Spiral welded tubes for burner pipes, flues, industrial stacks
Contact ZYTC Alloy for certified 321 stainless steel materials with complete traceability, ASTM/EN specifications, technical datasheets, and competitive pricing on standard sizes or custom-fabricated components. Email: daisy@zytcsteel.com WhatsApp/WeChat: +86 17335753350 |
