Basic Information
Classic nickel-chromium-molybdenum-tungsten austenitic solid solution alloy, low carbon and low silicon design, suppressing intergranular corrosion and σ phase precipitation at the source; typically maintains high corrosion resistance without post-weld heat treatment (unlike some alloys that require mandatory post-weld heat treatment).
Core Performance
Broad-spectrum corrosion resistant champion:** Resistant to sulfuric acid, hydrochloric acid, phosphoric acid, mixed acids, wet chlorine, hypochlorite, seawater, and high chloride ion solutions; extremely strong resistance to pitting corrosion, crevice corrosion, stress corrosion cracking (SCC), and intergranular corrosion, making it a "backup material" for extreme corrosion scenarios in chemical industries; performance covers most HC22 operating conditions, with superior performance in some reducing acids; maintains good toughness even at low temperatures down to -196°C.
Mechanics and processing:** Tensile strength at room temperature ≥690 MPa, yield strength ≥275 MPa, elongation ≥40%; weldable (primarily TIG/MIG, with strict heat input control); can be cold/hot processed into seamless pipes, welded pipes, elbows, tees, flanges, plates, and forgings; significant work hardening, requiring intermediate annealing.
Temperature range:** Long-term applicable to highly corrosive environments ≤650°C; good high-temperature oxidation and creep resistance, not suitable for ultra-high temperature long-term creep conditions.
Typical Application Scenarios
Chemical Industry: Mixed acid reactors, hydrochloric acid/sulfuric acid concentration units, wet chlorine treatment, pesticide/dye intermediate synthesis, fluorochemicals
Environmental Protection/Energy: Flue gas desulfurization (FGD) scrubbing towers, waste incineration tail gas treatment, seawater desalination high-pressure membrane shells, acidic wastewater treatment
Oil & Gas/Marine: Acidic gas treatment on offshore platforms, subsea pipelines, sulfur-containing crude oil processing
Semiconductor/Pharmaceutical: Ultra-high purity corrosive liquid transportation, special liquid cooling, sterile equipment for highly corrosive media
Appearance and Differentiation
C276, after pickling and passivation, has a silver-gray matte finish, a smooth surface without oxide scale or coating; it is heavier (higher density) than 2507 (density 7.8 g/cm³) and HC22 (8.69 g/cm³) of the same specification; its texture is warmer than duplex steel, and it has no obvious magnetism (it can be quickly distinguished from 2507/2205 with a magnet).