2101, 2304, 2205, 2507... Duplex Stainless Steel Coils
These four are all duplex stainless steels. When sorted by alloy content and corrosion resistance from low to high: 2101 < 2304 < 2205 < 2507. What they have in common is that their strength is twice that of 316L, and they possess excellent resistance to stress corrosion cracking. To put it simply: 2101 is an "economical lightweight option", 2304 is an "entry-level alternative", 2205 is an "all-round mainstay", and 2507 is a "super premium grade". The core differences lie in their Pitting Resistance Equivalent Number (PREN) and applicable scenarios. 🧪 Core Properties and Application Comparison · 2101 (Cost-effective economic grade): PREN approximately 26. Manganese and nitrogen are used to replace part of the nickel content, resulting in the lowest cost, while its yield strength is twice that of 304. Corrosion resistance is slightly better than 304 but significantly lower than 316L. Mainly used for bridge railings, truck frames, storage tanks, and other applications focusing on weight reduction and high toughness under mild corrosive conditions.· 2304 (Entry-level duplex steel): PREN approximately 25. Corrosion resistance falls between 304 and 316L, with slightly lower strength than 2101 but better toughness. Suitable for replacing 304 to reduce wall thickness, used in water heaters, heat exchangers, pulp digesters, and other medium and low temperature working conditions.· 2205 (Most widely used mainstream grade): PREN approximately 35. Its resistance to pitting and crevice corrosion far exceeds that of 316L, with outstanding resistance to chloride-induced stress corrosion cracking. It is the dominant choice for chemical pipelines, offshore platforms, flue gas desulfurization systems, and other medium to high corrosive environments, and is the most mature in the market.· 2507 (Super premium grade): PREN as high as 42+. It represents the top level in terms of corrosion resistance and strength among duplex steels. Specially designed for extremely harsh environments such as high-pressure seawater desalination pumps, subsea oil and gas pipelines, and strong acid heat exchangers, where 316L would suffer perforation within weeks. 💡 How to Choose? · Mild corrosion, primary goal is weight reduction (replacing 304/Q235) → 2101, the most affordable with high strength.· Better corrosion resistance than 304 required with limited budget (replacing 304) → 2304, cost-effective entry-level option.· Typical chemical/marine environments, balancing performance and cost → 2205, the first choice with the most extensive processing experience.· Seawater or strong acid conditions where 316L fails and extremely high strength is required → 2507 (however, it costs nearly twice as much as 2205 and is extremely difficult to process). ⚠️ Key General Precautions · Overheating is strictly prohibited: Duplex steels cannot be used long-term above 300°C, as harmful sigma phase precipitation will cause embrittlement.· Strict welding control: Interpass temperature must be below 150°C and heat input limited to ≤1.5 kJ/mm, otherwise corrosion resistance will degrade.· Processing differences: Higher strength grades (such as 2507) experience faster work hardening and demand higher-performance cutting tools. If you can provide the specific medium (e.g., chloride ion concentration/sulfuric acid concentration), operating temperature, and whether welding is required, I can help you with a more precise material selection.
Specifications
| Parameter | Specification |
|---|---|
| Material Grade | 2101,2304,2205,2507... |
| Standard | ASTM A240/A240M/GB/T713.7-2023 |
| Surface Finish | 2B, BA, NO. 4 ,8k,SB,HL,NO.1(Brushed) |
| Thickness Range | 0.3mm - 80mm (Customizable) |
| Width Range | 1000mm, 1219mm, 1250mm,1500mm,1800mm,2000mm(Customizable) |
Packing
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