How to Improve the Oxidation Resistance of Duplex Stainless Steel Pipes at High Temperatures
In demanding industries such as power generation, petrochemicals, and refining, pipelines often face extreme environments where both heat and corrosive elements are present. Improving the oxidation resistance of duplex stainless steel pipes at high temperatures is critical to extending service life, reducing maintenance costs, and ensuring safe and reliable operation.
At Ganyeah Group, we focus on engineering duplex stainless steel pipes with optimized compositions, advanced treatments, and surface technologies to deliver enhanced oxidation resistance for demanding applications.
ASTM A790 duplex stainless steel pipes for offshore use
1. Alloy Composition Optimization
Higher chromium content: Chromium forms a protective oxide layer, and increased levels improve oxidation resistance. Standard 2205 duplex stainless steel contains about 22% chromium, while super duplex grades like 2507 contain up to 25%.
Addition of molybdenum and nitrogen: Molybdenum enhances corrosion resistance at elevated temperatures, while nitrogen stabilizes the austenite phase and improves strength. A typical balance is 3–4% molybdenum and 0.18–0.32% nitrogen.
Balanced phase ratio: Maintaining a 50/50 ferrite–austenite balance ensures optimal mechanical and oxidation properties. Adjusting nickel content helps achieve this ratio.
2. Heat Treatment Improvements
Solution treatment: Rapid cooling after heating to 1040–1100 °C ensures a stable and balanced duplex microstructure.
Aging treatment: Post-heating at 550–600 °C improves tensile strength and ductility.
Cooling control: Optimized cooling rates reduce grain size (from 10 μm to 5 μm), increasing yield strength by 20–30%.
Avoiding 475 °C embrittlement: Long-term service above 475 °C should be avoided to prevent brittle phase precipitation.
3. Surface Treatment Technologies
Pickling and passivation: Acid treatment creates a dense passive oxide film that protects against oxidation.
Sandblasting: Enhances surface roughness and improves coating adhesion.
Mechanical polishing: Removes surface defects and reduces stress concentration points.
Electropolishing: Produces a smoother surface, improving resistance to high-temperature oxidation and corrosion.
4. Coating Applications
Ceramic coatings: Provide insulation and oxidation protection for internal and external pipe surfaces.
Epoxy coatings: Commonly used for oil and gas transportation pipelines to prevent internal corrosion.
Metallic coatings: Chrome or nickel plating enhances both surface appearance and corrosion resistance.
Why Choose Ganyeah Group
At Ganyeah Group, we specialize in manufacturing advanced stainless steel piping solutions tailored to challenging high-temperature applications. Our duplex stainless steel pipes are engineered to deliver superior oxidation resistance, durability, and consistent performance, helping clients achieve long-term reliability.
Enhancing the oxidation resistance of duplex stainless steel pipes at high temperatures requires a combination of advanced material design, optimized surface treatments, and proactive maintenance strategies. By choosing high-quality solutions from a trusted supplier, industries can secure safe, efficient, and cost-effective operations.
Contact Ganyeah Group today to discuss your project requirements and explore how our duplex stainless steel pipes can extend the performance of your critical systems.