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254SMO stainless steel seamless tube. Material grade: 254SMO super austenitic stainless steel (UNS S31254, 1.4547, 00Cr20Ni18MoCuN, F44). Chemical composition: Elements C, Si, Mn, Cr, Ni, S, P, Mo, N, Cu; contents ≤0.02, ≤0.8, ≤1.0, 19.5–20.5, 17.5–18.5, ≤0.01, ≤0.03, 6.0–6.5, 0.18–0.20, 0.5–1.0. Mechanical properties: Tensile strength, yield strength, elongation, hardness – ≥650, ≥310, ≥35 HB, ≤223. Physical properties: Density 8.24 g/cm3, melting point 1320°C–1390°C. Product characteristics: 254 SMO is a high-performance austenitic stainless steel. Due to its high molybdenum content, it possesses extremely high resistance to pitting and crevice corrosion. It was specifically designed and developed to resist corrosion caused by acids containing halides, such as hydrochloric acid mixed with chlorides, hydrofluoric acid, phosphoric acid, and sulfuric acid. 254 SMO also exhibits excellent resistance to uniform corrosion. In some cases, it can compare with expensive nickel alloys and titanium alloys. 254SMO has a very low carbon content, **which reduces the risk of carbide precipitation caused by heating ； It can still pass the Strauss intergranular corrosion test even after an hour of sensitization treatment at 600°C–1000°C. It can be welded without intergranular corrosion occurring. However, in hot concentrated nitric acid, these precipitates may cause intergranular corrosion in the heat-affected zone. In pure sulfuric acid, 254SMO exhibits strong corrosion resistance, but this resistance decreases at high concentrations. In sulfuric acid containing chloride ions, 254SMO exhibits the greatest corrosion resistance. At normal temperatures, 254SMO can be used in diluted hydrochloric acid, but care must be taken to avoid the presence of gaps. In fluorosilicic acid (H2SIF4) and hydrofluoric acid (HF), 254SMO can be used over a fairly wide range of concentrations and temperatures. At slightly higher temperatures, 254SMO also exhibits excellent resistance to crevice corrosion in seawater. Such as corrosion resistance in acidic solutions and oxidizing halide solutions required for pulp bleaching processes. Due to its higher nitrogen content, 254SMO has higher mechanical strength than other types of austenitic stainless steels. In addition, it also possesses high ductility and impact strength, as well as good weldability. 254SMO has a face-centered cubic crystal structure. Application areas: Ocean: marine structures in marine environments, seawater desalination, marine aquaculture, seawater heat exchange, etc. Environmental protection sector: flue gas desulfurization devices for thermal power generation, wastewater treatment, etc. Energy sector: nuclear power generation, comprehensive utilization of coal, tidal power generation, etc. Petrochemical industry: refining, chemical and petrochemical equipment, etc. Food industry: salt production, soy sauce brewing, etc. High-concentration chloride ion environment: paper industry, various bleaching systems.