321 Stainless Steel Sheet
321 Stainless Steel Sheet is a titanium-stabilized austenitic stainless steel ideal for high-temperature and welded applications where intergranular corrosion resistance is critical. Along with other common 300-series grades like 304, 316, and 317L, it is widely used in chemical, food, marine, aerospace, and industrial furnace applications, offering excellent corrosion resistance, mechanical strength, and durability.
- Description
321 Stainless Steel is an austenitic stainless steel stabilized with titanium, which improves resistance to intergranular corrosion after exposure to high temperatures. It is widely used in high-temperature industrial applications, especially where 304 stainless steel might suffer from sensitization during welding or heat treatment.
Chemical Composition
| Element | Content (%) |
|---|---|
| Chromium (Cr) | 17–19 |
| Nickel (Ni) | 9–12 |
| Titanium (Ti) | ≥ 5×C (stabilizer) |
| Carbon (C) | ≤ 0.08 |
| Manganese (Mn) | ≤ 2 |
| Silicon (Si) | ≤ 1 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.03 |
| Iron (Fe) | Balance |
Key Features:
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Titanium addition prevents chromium carbide precipitation during high-temperature exposure
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Excellent corrosion resistance similar to 304 stainless steel
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Maintains mechanical strength and toughness at elevated temperatures
Mechanical Properties
| Property | Typical Value |
|---|---|
| Tensile Strength | 520–750 MPa |
| Yield Strength | 205 MPa |
| Elongation | ≥ 40% |
| Hardness | 70–90 HRB |
| Temperature Range | Up to 870°C continuous service |
Highlights:
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High resistance to intergranular corrosion after welding or heat treatment
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Excellent ductility, formability, and weldability
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Non-magnetic in annealed condition
Corrosion Resistance
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Resistant to oxidation, mild acids, and atmospheric corrosion
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Performs well in high-temperature steam, chemical processing, and exhaust systems
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Suitable for industrial applications where sensitization of 304 might occur
Common Applications
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Industrial Furnaces & Heat Exchangers: Components exposed to high temperatures
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Chemical & Petrochemical Industry: Piping, reactors, and vessels
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Aerospace & Automotive: Exhaust systems, turbocharger components, heat shields
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Food & Pharmaceutical Industry: Equipment exposed to high temperatures during processing
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Architectural Applications: Panels and structures where elevated heat exposure occurs
Other Common 300-Series Stainless Steel Grades
| Grade | Key Features | Typical Applications |
|---|---|---|
| 304 / 1.4301 | Standard austenitic stainless steel, excellent corrosion resistance | Kitchen equipment, architectural panels, chemical tanks |
| 304L | Low carbon version, improved weldability | Welded tanks, piping, food processing equipment |
| 316 / 1.4401 | Higher corrosion resistance with molybdenum | Marine, chemical processing, pharmaceutical |
| 316L / 1.4404 | Low carbon, ideal for welded structures | Offshore equipment, chemical tanks |
| 317L | Enhanced corrosion resistance, higher molybdenum | Chemical, pharmaceutical, marine applications |
| 321 | Titanium-stabilized, high-temperature resistance | Furnaces, heat exchangers, welded high-temp components |
| 309 / 310 | High-temperature oxidation resistance | Furnace parts, heat treatment equipment |
