Steel-po’lat

STEELS

According to the chemiral composition, steel is carbon and alloyed. Carbon steel is less alloyed ( carbon content up to 0,25%), medium carbon (carbon content from 0,25% to 0,45%) yes more carbon (carbon content from 0,45% to 2,14%). Steel containing non-carbon alloying elements (chromium, nickel, tungsten, vanadium and others) is called alloy steel. Alloy steels are less alloyed, moderately alloyed, and more alloyed. According to their microstructures, steel is divided into perlite, martensite, austenite, ferrite and carbide.

According to their function, steels are divided into structural, tool, construction and special phusical properties steels. According to the method of production, steels are divided into:

1) ordinary quality, boiling, semi-boiling and non-boiling. Boiling steel is obtained by a certain degree of oxidation of the metal using silicon which contains up to 0,05% silicon in the steel. Boiling steel is 0,12% silicon and it is homogeneous. The structure of semi-welded steel is in te range of boiling and non-boiling steels, containing 0,05%-0,12% silicon.

2)high-quality steel-carbon or alloy, the content of sulfur and phosphorus should not exceed 0,04%.

3) high quality steel- carbon or alloy, in which the content of sulfur and phosphorus should not exceed 0,030 % and 0,035%, respectively. In such steels, non-metallic compounds are very rare and the letter “A” is added to the brant helmet.

VOCABLARY

STEEL-PO’LAT

CARBON-UGLEROD

ALLOYED-LEGIRLANGAN

SILICON-KREMNIY

BOILING-QAYNAYDIGAN

ORDINARY-ODDIY

HIGH-QUALITY- YUQORI SIFATLI

PHOSPHORUS-FOSFOR

CONTENT-MIQDORI

SULFUR-OLTINGUGURT

OXIDATION-OKSIDLANISH

NON-METALLIC-METALMAS

BRANT-MARKA

CHROMIUM-XROM

NICKEL-NIKEL

TUNGSTEN-WOLFRAM

VANADIUM-VANADIY

MICROSTRUCTURES-MIKROSTRUKTURA

COMPOUND-ARALASHMA

PRODUCTION- ISHLAB CHIQARISH