Analysis of carbon content in alloys

Measuring characteristics

Measured carbon concentration ranges: 0.03-9.999%

Certification

Type certificate of measuring instruments No. 5647-00 of the State Register of the Russian Federation.

Effect of carbon on steel properties

Carbon (chemical symbol - C) is a chemical element of the 4th group of the main subgroup of the 2nd period of the periodic system of Mendeleev, serial number 6, the atomic mass of the natural mixture of isotopes is 12.0107 g / mol.

With an increase in the carbon content in the steel structure, the amount of cementite increases, while the proportion of ferrite decreases. A change in the ratio between the components leads to a decrease in ductility, as well as to an increase in strength and hardness. The strength increases to a carbon content of about 1%, and then it decreases, as a coarse network of secondary cementite is formed.

Carbon affects the viscous properties. An increase in the carbon content increases the cold brittleness threshold and decreases the toughness.

Electrical resistance and coercive force increase, magnetic permeability and magnetic induction density decrease.

Carbon also influences technological properties. An increase in carbon content worsens the casting properties of steel (steels with a carbon content of up to 0.4% are used), workability by pressure and cutting, and weldability. It should be borne in mind that steels with a low carbon content are also poorly cut.

Classification of steels by carbon content

According to the purpose, steel (an alloy of iron with carbon) is divided into the following main groups: structural, tool and steel with special properties.

Structural steels are used for the manufacture of building structures, parts of machines and mechanisms, ship and carriage hulls, steam boilers, and other products. Structural steels can be both carbon (up to 0.7% C) and alloyed (the main alloying elements are Cr and Ni). The name of structural steel may reflect its direct purpose (boiler room, valve, spring-spring, shipbuilding, gun, shell, armor, etc.).

Tool steels are used for the manufacture of cutters, cutters, stamps, gauges and other cutting, impact-stamping and measuring tools. Steels of this group can also be carbonaceous (usually 0.8-1.3% C) or alloyed (mainly Cr, Mn, Si, W, Mo, V). High speed steel has become widespread among tool steels.

Steels with special physical and chemical properties include electrical steel, stainless steel, acid-resistant, scale-resistant, heat-resistant, steel for permanent magnets, etc. Many steels of this group are characterized by a low carbon content and a high degree of alloying.