Outokumpu SAF 2304® Duplex Stainless Steel Sheet,Plate

Outokumpu SAF 2304® Duplex Stainless Steel Sheet/Plate Product Information -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Sheet/Plate Synonyms -:- For detailed product information, please contact sales. -:

Outokumpu SAF 2304® Duplex Stainless Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Name: Outokumpu SAF 2304® Duplex Stainless Steel (UNS S32304 / EN 1.4362)** ## **Introduction** Outokumpu SAF 2304® is a **molybdenum-free, standard duplex stainless steel** that established the foundation for the modern duplex family. It offers a balanced microstructure of roughly 50% austenite and 50% ferrite, delivering a **compelling combination of high strength and excellent corrosion resistance**, specifically targeting superior performance over Type 316L austenitic stainless steel. SAF 2304® provides **approximately double the yield strength of 316L** and **significantly improved resistance to chloride stress corrosion cracking (SCC)**, making it a cost-effective, high-performance material for moderately aggressive environments. ## **Key Features** * **High Strength-to-Weight Ratio:** Yield strength (~400 MPa min.) is nearly double that of 316L, enabling significant weight reduction in structural components, tanks, and pressure vessels. * **Superior Stress Corrosion Cracking (SCC) Resistance:** Excellent resistance to chloride-induced SCC, a common failure mode for 300-series austenitic stainless steels, making it ideal for environments containing chlorides. * **Good General Corrosion Resistance:** Offers better resistance to pitting and crevice corrosion than 304L and comparable or better general corrosion resistance than 316L in many environments. * **Cost-Effective Alternative:** Provides a more affordable alternative to molybdenum-bearing standard duplex grades (like 2205) when the enhanced pitting resistance of molybdenum is not required, while still offering the core duplex benefits of strength and SCC resistance. --- ## **1. Chemical Composition (Typical Weight %)** The composition is designed for a balanced duplex structure without molybdenum. | Element | Content (%) | Element | Content (%) | | :------------- | :------------ | :------------- | :---------- | | Chromium (Cr) | 21.5 - 24.5 | Nickel (Ni) | 3.0 - 5.5 | | Molybdenum (Mo)| ≤ 0.6 | **Nitrogen (N)**| **0.05 - 0.20** | | Manganese (Mn) | ≤ 2.5 | Copper (Cu) | 0.05 - 0.60 | | Silicon (Si) | ≤ 1.0 | Carbon (C) | ≤ 0.030 | | Phosphorus (P) | ≤ 0.040 | Sulfur (S) | ≤ 0.015 | | **Iron (Fe)** | **Balance** | | | **Key Alloying Note:** The defining characteristic is the **absence of deliberate molybdenum (Mo) addition**. Corrosion resistance is achieved through high chromium and controlled nitrogen. **PREN Calculation:** PREN = %Cr + 3.3(%Mo) + 16(%N) ≈ **24 - 27** --- ## **2. Physical & Mechanical Properties (Typical - Annealed Condition)** | Property | Value / Range | | :-------------------------------------------- | :-------------------------------- | | Density | 7.8 g/cm³ | | Thermal Conductivity (20°C) | ~19 W/m·K | | Coefficient of Thermal Expansion (20-100°C) | ~13.0 x 10⁻⁶ /K | | Modulus of Elasticity | 200 GPa | | **Tensile Strength (Rm)** | **600 - 820 MPa** | | **Yield Strength (Rp0.2)** | **≥ 400 MPa** | | **Elongation (A in 50mm)** | **≥ 25 %** | | Hardness (Brinell) | 220 - 280 HBW | | **Impact Toughness (Charpy V-notch)** | **> 100 J at -40°C** | --- ## **3. Product Forms & Applications** **Available Product Forms:** * Sheet and Plate * Bar and Wire * Welded and Seamless Pipe & Tube * Strip **Primary Applications (Replacing 304L/316L where SCC is a risk):** SAF 2304® is ideal for applications requiring higher strength and SCC resistance than 316L, without the need for molybdenum's pitting resistance. * **Construction & Architecture:** Structural components, bridges, roofing, and façades in coastal or de-icing salt environments. * **Water & Wastewater Treatment:** Storage tanks, pressure pipes, basin covers, and structural supports. * **Chemical & Process Industry:** Tanks, vessels, and piping for mildly corrosive chemicals, organic acids, and sulfate-containing media. * **Pulp & Paper Industry:** Storage tanks, washer drums, and equipment exposed to neutral sulfite liquors. * **Food & Beverage:** Brewing tanks, fermentation vessels, and structural supports. * **Heat Exchangers:** For cooling water systems with moderate chloride levels where 316L may suffer from SCC. * **Transportation:** Structural parts in railcars and ships. --- ## **4. International Standards & Approvals** SAF 2304® is the original duplex grade and is well-established in international standards. | Standard Type | Standard Number & Designation | Notes | | :------------------ | :--------------------------------------------------------------------------------------------------------------------------- | :-------------------------------------------------------------------- | | **Unified Numbering System (UNS)** | **S32304** | The standard UNS designation for this molybdenum-free duplex alloy. | | **EN / EURONORM (Europe)** | **1.4362** | The common European material number. | | | EN 10088-2: Sheet/Plate/Strip
EN 10088-3: Bars
EN 10216-5: Seamless pressure tubes | Widely covered in European product standards. | | **ASTM (USA)** | **ASTM A240** (Plate/Sheet/Strip)
**ASTM A789/A790** (Seamless/Welded Pipe & Tube)
**ASTM A276** (Bar) | Fully standardized in key ASTM material specifications. | | **Other Standards** | JIS G4304 / G4305 (Japan) - SUS323J1
GB/T 20878 (China) | Included in major national standards. | --- ## **Important Technical & Procurement Note** SAF 2304® is a **proprietary Outokumpu product** that meets international standards. For procurement, specifying **"UNS S32304"** or **"EN 1.4362"** alongside the Outokumpu brand name is recommended. * **Fabrication:** Good weldability using standard duplex practices. Filler metals like 2209 are commonly used. Forming requires higher forces than for austenitic grades. * **Selection Rationale:** Its primary advantage is offering **duplex-level strength and SCC resistance at a lower cost than 2205**. It is an **excellent upgrade from 316L** where pitting resistance is adequate but SCC failure is a concern. It is **not suitable** for applications requiring the high pitting resistance of molybdenum-bearing grades (e.g., seawater, strong chlorides). * **Certification:** Always require a **material test certificate (MTC/CMTR)** confirming compliance with the ordered standard (e.g., ASTM A240). -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Specification Dimensions Size： Diameter 20-1000 mm Length <7287 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: Outokumpu SAF 2304® Duplex Stainless Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Outokumpu SAF 2304® Duplex Stainless Steel Sheet,Plate -:- For detailed product information, please contact sales. -: Chemical Identifiers Outokumpu SAF 2304® Duplex Stainless Steel Sheet,Plate -:- For detailed product information, please contact sales. -:

Packing of Outokumpu SAF 2304® Duplex Stainless Steel Sheet/Plate -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and Steel Sheet/Plate drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3758 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition