Duplex stainless steel comes in several grades, each with its own specific composition and properties. The most common duplex stainless steel grades are: Duplex 2205 (UNS S32205/S31803): This grade contains approximately 22% chromium, 5-6% nickel, 3% molybdenum, and a small amount of nitrogen. Duplex 2205 offers excellent corrosion resistance in a wide range of corrosive environments, including chloride-containing media such as seawater and brine solutions. It has high strength and good weldability, making it suitable for various applications in industries such as oil and gas, chemical processing, and marine engineering. Duplex 2507 (UNS S32750): Duplex 2507 contains higher chromium (24-26%), molybdenum (3-5%), and nitrogen compared to Duplex 2205. This grade offers superior corrosion resistance and higher strength than Duplex 2205, particularly in highly corrosive environments with high chloride content. Duplex 2507 is often used in aggressive environments such as offshore oil and gas production, chemical processing, and desalination plants. Duplex 2304 (UNS S32304): Duplex 2304 contains lower chromium (21-23%), nickel (3.5-5.5%), and molybdenum (0.05-0.6%) compared to Duplex 2205 and 2507. It offers good corrosion resistance in mild to moderately corrosive environments and higher strength than austenitic stainless steels. Duplex 2304 is commonly used in structural and architectural applications, as well as in chemical processing equipment and transportation vessels. Duplex LDX2101 (UNS S32101): Duplex LDX2101 contains lower chromium (21.5-22.5%), nickel (1.5-2.5%), and molybdenum (0.1-0.8%) compared to other duplex grades. It offers good corrosion resistance, high strength, and low thermal expansion, making it suitable for structural and industrial applications. Duplex LDX2101 is often used in structural components, storage tanks, and transportation equipment. These are some of the most commonly used grades of duplex stainless steel. Each grade offers a unique balance of corrosion resistance, mechanical properties, and cost-effectiveness, allowing engineers and designers to select the most suitable grade for specific applications based on performance requirements and environmental conditions.