Hangbo Alloy Group supplies a variety of XM-19 (UNS S20910) super austenitic stainless steel products, including round bars, plates, strips, seamless tubes, forgings, and wires. Below is a comprehensive description of XM-19 super austenitic stainless steel.
1. Introduction to XM-19
Description: XM-19 (UNS S20910, also known as Nitronic 50) is a high-performance nitrogen-strengthened super austenitic stainless steel, mainly composed of chromium, nickel, molybdenum, and nitrogen. It features a fully austenitic structure (no ferrite phase), integrating excellent corrosion resistance (especially to chloride pitting/crevice corrosion) and good mechanical properties. It exhibits outstanding resistance to high-temperature oxidation and chloride stress corrosion cracking (SCC), stable performance in the temperature range of -270°C to 540°C, and high tensile strength (≥690 MPa). These characteristics make it ideal for ultra-harsh environments with high-concentration corrosive media (e.g., high-temperature chloride solutions) and high-temperature service requirements.
International Equivalents:
USA: UNS S20910, ASTM XM-19 (Nitronic 50)
CHINA: 06Cr21Ni23Mo10N (per GB/T 20878 standard)
Europe: EN 1.4659, DIN X1CrNiMoCuN24-22-8
2. Standards for XM-19
Plates/Sheets: ASTM A240/A240M (Grade S20910), GB/T 4237, EN 10088-2
Round Bars: ASTM A276 (Grade S20910), GB/T 1220, EN 10088-3
Seamless Tubes: ASTM A789/A790 (Grade S20910), GB/T 14976, EN 10216-5
Forgings: ASTM A182/A182M (Grade S20910), GB/T 1221, EN 10222-5
3. Chemical Composition of XM-19
| Element | Content (%) |
|---|---|
| Carbon (C) | ≤ 0.06 |
| Chromium (Cr) | 20.5-23.5 |
| Nickel (Ni) | 11.5-13.5 |
| Molybdenum (Mo) | 1.50-3.00 |
| Nitrogen (N) | 0.20-0.40 |
| Niobium(Nb) | 0.10-0.30 |
| Silicon (Si) | ≤0.75 |
| Manganese (Mn) | 4.0-6.0 |
| Phosphorus (P) | ≤ 0.040 |
| Sulfur (S) | ≤ 0.030 |
| Iron (Fe) | Balance |
4. Physical Properties of XM-19
| Property | Value |
|---|---|
| Density | 7.88 g/cm³ |
| Melting Range | 1415-1450 °C |
5. Material Characteristics of XM-19
Superior Chloride Corrosion Resistance: PREN (Pitting Resistance Equivalent Number) ≥ 42, far exceeding 316L/2205, with excellent resistance to pitting, crevice corrosion, and chloride SCC in high-temperature, high-concentration chloride media.
High-Temperature Stability: Maintains stable mechanical properties and oxidation resistance at temperatures up to 540°C; suitable for high-temperature corrosive environments (e.g., flue gas desulfurization systems).
Good Mechanical Properties: Tensile strength (≥690 MPa) and yield strength (≥380 MPa) are higher than ordinary austenitic stainless steels, with excellent ductility and low-temperature toughness (no brittle fracture at -270°C).
Excellent Weldability: Compatible with standard welding methods (TIG, MIG, submerged arc welding); no post-weld heat treatment required, and weld joints retain good corrosion resistance and strength.
Wear & Erosion Resistance: Nitrogen addition enhances surface hardness, improving wear resistance compared to 316L/304.
6. Applications of XM-19
Chemical & Petrochemical Industry: Used in high-temperature chloride-containing reactors, acid distillation columns, and sulfuric acid/hydrochloric acid handling equipment; resists strong corrosive media.
Flue Gas Desulfurization (FGD): Applied to FGD system components (absorbers, spray nozzles, pipelines); withstands high-temperature acidic flue gas and chloride erosion.
Seawater & Marine Engineering: Employed in deep-sea oilfield pipelines, offshore platform heat exchangers, and high-temperature seawater equipment; resists long-term seawater corrosion.
Nuclear Industry: Used in nuclear power plant coolant pipelines and corrosion-resistant components; meets high-temperature, high-pressure, and corrosion resistance requirements.
Pharmaceutical & Food Processing: Applied to high-purity chemical storage tanks and food processing equipment; resists mild acids and ensures hygiene and corrosion resistance.
