Steel A75 (У7АВ)

  • U16 steel (EI336)
  • U9A steel
  • U9 steel
  • U8GA steel
  • U8G steel
  • U8A steel
  • U8 steel
  • U7A steel
  • U7 steel
  • U12A steel
  • U12 steel
  • U11A steel (U11)
  • U10A steel
  • U10 steel
  • Steel AU10E (ASU10E)
  • A85 steel
  • Steel A75 (U7AB)

    • Designation

    Name The value
    Designation GOST Cyrillic А75
    Designation GOST Latin A75
    Transliteration A75
    By chemical elements -
    Name The value
    Designation GOST Cyrillic У7АВ
    Designation GOST Latin U7AB
    Transliteration U7AV
    By chemical elements 7NW

    Description

    A75 steel is used: for the manufacture of shafts, reels, winding shafts, springs and other parts of the complex form of movements and instruments, followed by heat treatment under special conditions and using different coatings and coating to prevent corrosion; details of the watch industry, subjected to subsequent thermal treatment.

    Standards

    Name Code Standards
    Bars and shapes В32 TU 14-1-1147-74, TU 14-1-2607-78, TU 14-1-3390-82, TU 14-1-505-73, TU 14-1-924-74, TU 14-130-263-94

    Chemical composition

    Standard C S P Mn Cr Si Ni Fe Cu
    TU 14-1-3390-82 0.7-0.8 0.18-0.24 0.04-0.08 0.4-0.7 ≤0.25 ≤0.3 ≤0.25 Rest ≤0.3
    TU 14-1-505-73 0.7-0.8 0.18-0.24 0.04-0.08 0.4-0.7 ≤0.25 ≤0.3 ≤0.25 Rest -
    Fe is the basis.
    According to TU 14-1-505-73 by agreement of the parties for special purpose hardware A75 steel should be supplied with narrowed content limits of elements without treatment with synthetic slag and purging with argon.

    Mechanical properties

    Section, mm σU, MPa
    Bars with special surface finish as supplied on the other 14-1-2607-78
    1-4 740-980
    4-6 690-880
    Bars with special surface finish as supplied on the other 14-1-3390-82
    1-4 780-980
    4-6 740-880
    6-12 690-830
    The silverfish in the state of delivery on the other 14-1-924-74
    0.4-0.95 736-932

    Description mechanical marks

    Name Description
    σU Limit short-term strength

    Technological properties

    Name The value
    Macrostructure and pollution The fracture of steel bars on the other 14-1-2607-78 controlled on the bars with diameter 3.0 mm and above shall be homogeneous and fine-grained. The break should be free of voids, supernote, delaminations, cracks, bubbles and inclusions visible to the naked eye. Decarbonisation on the bars is not allowed.
    Microstructure The microstructure is granular pearlite silverfish on the other 14-1-924-74 should correspond to points 2-6 of the scale 2 GOST 8233. The microstructure of the steel bars on the other 14-1-2607-78 should consist of uniformly distributed fine pearlite and must comply with points 1-4 of the scale GOST 801.
    Particularities of production of goods Rod on the other 14-1-505-73 comes Beloretsky metallurgical plant. Bars on the other 14-1-2607-78 supplied in cold-worked condition.