Carbon Structural Steel Standard

Standard: GB/T3190-1996

Features and Scope:

Quality carbon structural steel is the material that the carbon content less than 0.8%. Parathion and non-metallic inclusions in this steel contained less than carbon structural steel, mechanical performance is more excellent.

Quality carbon structural steel (GB/T699-1999):

Containing carbon (C) element for deoxidation and contains a certain amount of silicon (Si) (generally not more than 0.40%), manganese (Mn) (generally not more than 0.80% to 1.20% higher) alloying elements in steel, in addition, without other alloying elements the (except residual element). Such steel must also ensure that the chemical composition and mechanical properties. Sulfur (S), phosphorus (P) content of impurity elements is generally controlled at 0.035% or less. Control 0.030% called high-quality steel grades "A" should be added later, for example 20A; the P control 0.025% 0.020%, S control, said the premium-quality steel, the grade should be followed plus the "E" to show the difference. For other residual alloying elements from the raw material into the steel, such as chromium (Cr), nickel (Ni), copper (Cu), etc. The content of the general control Cr ≤ 0.25%, Ni ≤ 0.30% Cu ≤ 0.25%. Some grades of manganese (Mn) content of up to 1.40%, known as manganese steel.Such steel is dependent amount of adjustment carbon (C) to improve the mechanical properties of the steel, and therefore, according to the level of carbon content, such steels can be divided into:
Low carbon steel - carbon content is generally less than 0.25%, such as 10, 20 are steel, etc.;

Medium carbon steel - carbon content generally between 0.25 to 0.60%, such as 35,45 steel, etc.;

High carbon steel - generally greater than the carbon content of 0.60%. Such steel is generally not used for the manufacture of steel pipes.

In fact, the carbon content no clear boundaries between them.Such steel production uses a wider, more generally rolling (forging) made round, square, flat, such as profiles, sheet and seamless steel pipe. Mainly used in the manufacture of the general structure and mechanical structure of zero, components, and building structural parts and transmission fluid piping. According to the requirements, sometimes need to heat treatment (normalizing or quenching).

The classification of high-quality carbon structural steel:

    Quality carbon structural steel can be divided into three categories: low-carbon steel (C ≤ 0.25%), carbon content in carbon steel (C 0.25-0.6%) and high carbon (C> 0.6%).
    Quality carbon structural steel normal manganese (manganese 0.25% -0.8%) and high manganese content (0.70% -1.20% manganese) were divided into manganese content, which has good mechanical properties and processing performance.
    1. High-quality carbon structural steel hot-rolled steel sheet and strip
    Quality carbon structural steel hot-rolled steel sheet and strip for the automotive, aerospace, industrial and other parts. 30 and 30 grade steel rimmed steel: 08F, 10F, 15F; killed steel: 08,08 Al, 10,15,20,25,30,35,40,45,50, 25 and 25 for the low-carbon steel plate medium carbon steel plate.
    2.Quality carbon structural steel plates and wide strips
    Quality carbon structural steel plates and wide strips used for a variety of mechanical structures. Steel grades for the low-carbon steel, including: 05F, 08F, 08,10 F, 10,15 F, 15,20 F, 20,25,20 Mn, 25Mn; including medium carbon steel: 30,35,40,45,50 55,60,30 Mn, 40Mn, 50Mn, 60Mn; high carbon steel, including: 65,70,65 Mn, etc..