In the duplex stainless steel sector, grades 2205 and 2507 hold significant positions due to their outstanding strength and corrosion resistance. Both belong to the duplex steel family, yet exhibit distinct differences in alloy composition and performance gradients, leading to precise differentiation in their applicable scenarios. Industry experts emphasize that selecting the appropriate grade based on the severity of operating conditions is crucial for balancing safety and cost-effectiveness.

Core differences stem from alloy composition: both have ≤0.03% carbon content, but 2507 contains higher levels of chromium, molybdenum, and nitrogen. Grade 2205: Chromium 21%-23%, Molybdenum 2.5%-3.5%, Nitrogen 0.08%-0.20%; Tensile strength 620-800 MPa, Yield strength 450-620 MPa; Balanced performance characteristics. Grade 2507 contains 24%-26% chromium, 3.0%-5.0% molybdenum, and 0.24%-0.32% nitrogen, with tensile strength ≥795 MPa and yield strength ≥550 MPa. Its chloride corrosion resistance significantly surpasses Grade 2205, making it a typical super duplex steel.

Application scenarios are differentiated by corrosion resistance and strength grades. 2205 offers outstanding cost-effectiveness, suitable for conventional corrosion environments like petrochemical pipelines, seawater desalination equipment, and wastewater treatment valves, making it a versatile “universal grade.” 2507 is tailored for extreme conditions such as deep-sea oil extraction, strong acid reactors, and flue gas desulfurization systems. Its price is 1.5-2 times that of 2205, and it demands stricter processing and welding techniques.