XM-19

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.​.

Behaviour that matters in service

• 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.​.

Typical applications

• Chemical & Petrochemical Industry — Used in high-temperature chloride-containing reactors, acid distillation columns, and sulfuric acid/hydrochloric acid handling equipment; resists strong corrosive media.​.
• 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.