321 Stainless Steel Sheet / Plate

We supply a full range of 321 stainless steel sheets and plates with reliable quality and stable performance for high-temperature and welded applications. Our 321 stainless steel sheets are available in various thicknesses, widths, surface finishes, and processing options to meet industrial, mechanical, and fabrication requirements.

Specification — 321 Stainless Steel Sheet

321 Stainless Steel Sheet / Plate

321 stainless steel is a titanium-stabilized austenitic stainless steel based on 304 chemistry. The addition of titanium (Ti ≥ 5×C) effectively prevents chromium carbide precipitation, providing excellent resistance to intergranular corrosion, especially after welding or exposure to elevated temperatures.

Compared with 304 stainless steel, 321 stainless steel sheet offers superior high-temperature stability and improved post-weld corrosion resistance, making it suitable for service temperatures up to 800°C. Customized cutting, surface treatment, and thickness control are available to meet specific application needs.

Chemical Composition (Typical, %)

Mechanical Properties (Typical)

Heat Treatment of 321 Stainless Steel Sheet / Plate

1. Solution Annealing

Temperature range: 1040–1100 °C

Process: Heating followed by rapid cooling (water quenching or air cooling)

Purpose:
Dissolves carbides, restores austenitic structure, and ensures optimal corrosion resistance and ductility.

2. Stabilization Treatment (Optional)

Applied after solution annealing or welding for critical applications.

Helps stabilize titanium carbides and further improves resistance to intergranular corrosion in long-term high-temperature service.

3. Hardening

321 stainless steel cannot be hardened by heat treatment.
Mechanical strength is mainly influenced by cold working.

Note: Heat treatment for 321 stainless steel is primarily used to improve corrosion resistance and high-temperature stability, not for strength enhancement.

Features of 321 Stainless Steel Sheet / Plate

High-Temperature Resistance:
Maintains stable mechanical properties and corrosion resistance at elevated temperatures up to 800°C.

Intergranular Corrosion Resistance:
Titanium stabilization prevents chromium carbide precipitation, making it suitable for welded components without post-weld heat treatment.

Good Weldability:
Excellent weldability using standard stainless steel welding methods with minimal risk of weld decay.

Mechanical Stability:
Good strength, ductility, and dimensional stability for fabrication and forming processes.

Alternative to 304 for High-Temperature Use:
Offers better high-temperature performance than 304 while remaining more economical than 310S.

Applications of 321 Stainless Steel Sheet / Plate

High-Temperature Equipment:
Heat exchangers, furnace components, exhaust systems
Recommended: medium to thick plates

Welded Structures:
Pressure vessels, piping systems, expansion joints
Recommended: annealed sheets for welding

Aerospace & Automotive:
Exhaust manifolds, thermal shields, engine components
Recommended: precision-cut sheets

Chemical & Petrochemical Industry:
Reactors, processing equipment, structural linings
Recommended: corrosion-resistant surfaces

Power & Energy Industry:
Boilers, superheaters, high-temperature ducts

321 stainless steel sheets are especially suitable for applications involving welding and continuous exposure to elevated temperatures, where standard 304 stainless steel may fail.

FAQ – 321 Stainless Steel Sheet / Plate

Q1: What is the difference between 321 and 304 stainless steel sheet?
321 contains titanium, which improves resistance to intergranular corrosion and high-temperature stability compared to 304.

Q2: Is 321 stainless steel sheet suitable for welding?
Yes. 321 stainless steel is specifically designed for welded applications without the need for post-weld heat treatment in most cases.

Q3: Can 321 stainless steel sheet be used at high temperatures?
Yes. It performs well at temperatures up to approximately 800°C.

Q4: Can 321 stainless steel sheet be hardened by heat treatment?
No. Like other austenitic stainless steels, it cannot be hardened by heat treatment.

Q5: Is 321 stainless steel sheet magnetic?
No. It is generally non-magnetic in annealed condition; slight magnetism may occur after cold working.