Steel-po’lat
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STEELS
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 Download 473.33 Kb. Do'stlaringiz bilan baham: |
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