What Is 329 Stainless Steel?
What Type of Stainless Steel Is 329?
329 stainless steel belongs to the duplex stainless steel family, containing a mixed microstructure of austenite and ferrite. This dual-phase structure provides higher tensile strength, better chloride corrosion resistance, improved stress corrosion cracking resistance, and better toughness than ferritic stainless steel.
Chemical Composition of 329 Stainless Steel
| Element | Content (%) |
|---|---|
| Chromium (Cr) | 23.0 – 28.0 |
| Nickel (Ni) | 2.5 – 5.0 |
| Molybdenum (Mo) | 1.0 – 2.0 |
| Carbon (C) | ≤ 0.08 |
| Manganese (Mn) | ≤ 2.0 |
| Silicon (Si) | ≤ 1.0 |
| Phosphorus (P) | ≤ 0.04 |
| Sulfur (S) | ≤ 0.03 |
| Iron (Fe) | Balance |
Mechanical Properties of 329 Stainless Steel
| Property | Value |
|---|---|
| Tensile Strength | ≥ 620 MPa |
| Yield Strength | ≥ 450 MPa |
| Elongation | ≥ 20% |
| Hardness | ≤ 290 HB |
Main Advantages of 329 Stainless Steel
- Excellent corrosion resistance in seawater, chloride, acidic media, and petrochemical environments.
- High mechanical strength suitable for pressure-containing components.
- Good heat resistance for heat exchangers and industrial heating systems.
- Long service life with reduced maintenance costs.
329 Stainless Steel vs 316L Stainless Steel
329 stainless steel provides much better chloride corrosion resistance, higher strength, and superior stress corrosion cracking resistance than 316L. Although it may have a higher material cost, its durability and longevity often reduce total project costs.
Common Product Forms of 329 Stainless Steel
- Round Bar: Shafts, valves, pump parts, precision machining.
- Pipes and Tubes: Heat exchangers, pipelines, offshore piping, pressure equipment.
- Plates and Sheets: Pressure vessels, chemical tanks, marine structures, industrial fabrication.
- Forgings: Flanges, rings, heavy industrial components, high-pressure systems.
Standards and Certifications
329 stainless steel products may comply with ASTM, ASME, EN, DIN, JIS, and GB standards, including ASTM A240, ASTM A276, ASTM A312, ASTM A182, EN 10088. SAKY STEEL supports customized manufacturing according to customer specifications.
Applications of 329 Stainless Steel
- Petrochemical Industry: Process piping, storage tanks, heat exchangers, pressure vessels.
- Marine Engineering: Offshore platforms, shipbuilding, seawater handling systems.
- Oil and Gas Industry: Pipeline systems, wellhead equipment, refinery components, offshore drilling.
- Heat Exchanger Systems: Industrial heat exchanger tubes and shells.
Quality Inspection and Testing
SAKY STEEL provides:
- PMI Testing
- UT Testing
- Chemical Composition Analysis
- Mechanical Property Testing
- Hardness Testing
- Dimensional & Surface Inspection
- EN 10204 3.1 Certificates
- Third-Party Inspection (SGS, BV, TÜV)
Packaging and Export Service
Export packing options include wooden cases, waterproof wrapping, pallets, bundle packing, and customized packaging. SAKY STEEL exports globally to Europe, Middle East, North America, South America, and Southeast Asia.
FAQ
- Is 329 stainless steel duplex stainless steel? Yes, it has a mixed ferritic and austenitic microstructure.
- What is the advantage over 316L? Higher strength, better chloride resistance, and superior stress corrosion cracking resistance.
- Is it suitable for seawater? Yes, highly suitable for marine environments.
- Can SAKY STEEL provide EN 10204 3.1 certificates? Yes, including PMI and third-party inspection reports.
Conclusion
329 stainless steel is a high-performance duplex material for demanding industrial applications, offering superior corrosion resistance, high mechanical strength, and long service life. SAKY STEEL supplies 329 stainless steel bars, pipes, tubes, plates, and custom products with global export experience and strict quality control.
Contact SAKY STEEL
Website: SAKY STEEL Official Website
Contact us for quotations, technical support, custom sizes, EN 10204 3.1 certificates, and global export solutions.
Post time: May-28-2026