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Varieties of steel, Code

     Steel variety, different performance. Guangdong Steel by Usage structural steel, tool steel and special steel. Divided by the chemical composition of carbon steel and alloy steel. Carbon steel containing at A into low carbon steel (<0.25%) of carbon ((0.25% 0.6%), the carbon I <0.06% of steel known as wrought iron, containing 0f> 2 % is called iron.
     By refining method is divided into open-hearth steel, top-blown converter steel raise gas, side-blown basic oxygen converter steel and electric steel. By casting methods into boiling steel, semi-killed steel, killed steel and special killed steel. Steel Steel is commonly used carbon steel and low alloy steel and special steel.
     Carbon structural steel (GB 700-88)
     China's production of carbon steel into Q195, Q215, Q235, Q255, Q275 five. Q Pinyin first letter indicates the yield strength, yield strength figures represent the lower limit (N / mm =), low yield strength steel, ductility, toughness, good welding performance. Steel steel is mainly Q235, its carbon content between 0.1200 f "0.22%, strength, ductility, weldability are good. Carbon steel representation Q235-XX, XX represents quality t grading and pouring methods such as Q235-A-F, Q235-C and so on.
     It is divided into four quality Q235 steel grade: A, B, C, D, A grade quality Worst A, D level best, A, Class B divided by deoxygenation were divided into boiling steel (F), semi-killed steel (b), C grade was killed steel (Z), D grade special killed steel (TZ). which killed steel (Z), special killed steel (TZ) symbols can not write.
     When carbon structural steel factory, a certificate shall have the chemical composition and mechanical properties of the chemical composition requirements of carbon, manganese, silicon, sulfur, A monument containing the appropriate level of compliance with the provisions of the mechanical performance requirements of yield strength o,, tensile strength au, cold bending test qualified people and elongation (A grade steel does not require carbon, manganese containing f and cold bending test), B, C, D level were key additional requirements 20C, oC,-20C V-notched specimen , toughness pass yield strength a, B, C, D level key material, tensile strength, elongation value of the same, but the thickness t> 16mm steel, and its value is reduced.