Shanghai Bao Steel Co., Ltd. specializes in the production margin S31254,00Cr20Ni18Mo6CuN, F44,254SMo manufacturers, 254SMo tube, 254SMo plate, 254SMo round, 254SMo strip, 254SMo pipe, 254SMo pipe fittings, 254SMo forgings, 254SMo flange, 254SMo wire, 254SMo and other accessories. 254SMO UNS S31254W.-Nr. Chemical composition of the alloy 1.4547 254SMO% nickel-chromium-molybdenum copper and manganese silicon carbon nitrogen phosphorus sulfur 254SMO minimum 17.5 19.5 6 0.5 0.18 maximum 18.5 20.5 6.5 1 0.22 0.02 1 0.8 0.03 0.01 254SMO physical properties of density 8.0 g / cm3 1320-1390 ℃ 254SMO melting point alloy at room temperature mechanical properties of the minimum tensile strength Rm N / mm2 yield strength RP0.2N / mm2 Elongation A5% 650 300 35 This alloy has the following characteristics: high molybdenum content and high chromium and nitrogen content makes 254SMO has a very good resistance to corrosion and crevice corrosion resistance point performance. Copper is added to improve the corrosion resistance of certain acids. In addition, due to its high nickel content and high chromium and molybdenum content, so 254SMO has good resistance to stress corrosion cracking performance. A lot of experiments and extensive field experience shows that even at slightly higher temperatures, 254SMO in seawater is also highly resistant to crevice corrosion resistance, only a few types of stainless steel having such properties. 254SMO corrosion resistance in acidic solution and the oxidizing halides such as paper bleaching solution needed to produce the strongest with corrosion-resistant nickel-based alloys and titanium alloys compared to the United States. Since 254SMO has a high nitrogen content, and therefore its mechanical strength than other types of austenitic stainless steel is higher. Furthermore, 254SMO also has high ductility and impact strength and good weldability. 254SMO high molybdenum content so that it can have a higher annealing rate of oxidation, so that the pickling of stainless steel has a rougher surface than ordinary. But this does not adversely affect the corrosion resistance of the steel. 254SMO metallurgical structure 254SMO face-centered cubic lattice structure. In order to obtain austenitic structure, 254SMO generally at a temperature of 1150-1200 ° C annealing. In some cases, the material may have a metal intermediate with (χ-phase and α phase) marks. But in general, they have no adverse effect on impact strength and corrosion resistance. When placed in the range of 600-1000 ° C, these phases may be precipitated in the grain boundaries. 254SMO 254SMO corrosion resistance of the carbon content is very low, which means that the heating caused by the risk of carbide precipitation is very small. The steel in the 600-1000 degrees Celsius even after one hour after treatment sensitized still Strauss through the intergranular corrosion test (Strauss Test ASTMA262 procedure E). However, due to the high alloy content of the steel. In the above temperature range the metal intermediate phase may precipitate in the grain boundaries. These precipitates will not make the steel to intergranular corrosion occurs between dangerous when used in corrosive media. It can be welded without intergranular corrosion. However, in hot concentrated nitric acid, these precipitates may cause intergranular corrosion in the heat affected zone. Containing such as chloride, bromide or iodide solution immediately to ordinary stainless steel pitting, crevice corrosion or stress corrosion cracking in the form of localized corrosion by erosion. However, in some cases, the presence of halide accelerated uniform corrosion. In particular it is especially the case in the presence of halide of a non-oxidizing acid. In pure sulfuric acid, 254SMO than 316 stainless steel has a much larger general corrosion resistance. But (NO8904) stainless steel in high concentrations compared with the 904L, corrosion resistance 254SMO are weaker. In sulfuric acid containing chlorine ions, 254SMO have the greatest corrosion resistance force. May occur due to localized corrosion and uniform corrosion, so the 316 ordinary stainless steel can not be used hydrochloric acid, but in general the temperature 254SMO can be used to dilute hydrochloric acid. In the following areas do not have to worry about the occurrence of the boundary line pitting. But must try to avoid the presence of the gap. In the fluorine silicic acid (H2SiF4) and hydrofluoric acid (HF), the general corrosion-resistant stainless steel range is very limited, and it can be applied 254SMO in a wide range of concentrations and temperatures. There 254SMO Application field: 254SMO alloy is a versatile material, can be applied in many industrial fields: petroleum, petrochemical equipment, such as petrochemical equipment bellows. Pulp and paper bleaching equipment, such as pulp digesters, bleaching equipment, filtration and washing used in the barrel and cylinder pressure roll. Power plant flue gas desulfurization equipment, mainly used parts are: the absorption tower, flue, stall doors, trim, spray systems. Or sea water treatment system at sea, such as power plants using sea water to cool the thin-walled Condenser, desalination equipment, even though the water may not flow in the device can also be used. Desalination industries, such as salt or desalination equipment. A heat exchanger, especially in the working environment of chloride ion exchanger. High chromium and molybdenum content and high nitrogen content makes 254SMO has very good resistance to pitting and crevice corrosion resistance properties. Copper is added to improve the corrosion resistance of certain acids. In addition, due to its high nickel content and high chromium and molybdenum content, so 254SMO has good resistance to stress corrosion cracking performance. Widely used in marine and industrial desalination, water treatment, chlorine and chlorine dioxide bleaching equipment stage equipment and flue gas desulfurization devices. Po-edge company mainly production and supply of high-temperature alloy grades are: (GH2132, GH3030, GH3039, GH3128, GH4145, GH4169, GH4180) Inconel alloys: (Inconel600, Inco601, Inconel625, Inconel690, Inconel718, Inconel617, Inconel725) Inconel Loy alloys: (Incoloy800, Incoloy800H, Incoloy800HT, Incoloy825, Incoloy925, Incoloy926, Incoloy DS) Hastelloy: (Hastelloy C-276, Hastelloy C, Hastelloy X, Hastelloy B, Hastelloy B-2) Monel: (Monel400 , MonelK500, Monel450) corrosion resistant alloys: (NS111, NS112, NS142, NS312, NS313, NS321, NS333, NS334, NS335, NS336) precision alloy: (Cr20Ni80,1J50,1J79,3J53,4J29,4J36) special stainless :( 904L, A4 steel, U3 steel, Invar36, Alloy20Cb-3, Al-6XN, 253MA, XM-19,310Si, 316LMod, 2205,2507, S31254,15-5PH, 15-7PH, 17-7PH, 17-4PH) especially large thick pipe for advantage.