Steel U7

  • 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 У7
    Designation GOST Latin U7
    Transliteration U7
    By chemical elements 7

    Description

    Steel u7 is used: for the manufacture of tools for working wood (axes, kolunov, chisels, bits); pneumatic tools small size (chisels, swages, dies); forging dies; needle wire; machinist’s tools (hammers, sledge hammers, drifts, screwdrivers, compound pliers, nippers, oblique cutting pliers, etc.).

    Standards

    Name Code Standards
    Tape В34 GOST 10234-77
    Sheets and strips В23 GOST 103-2006
    Bars and shapes В22 GOST 1133-71, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
    Bars and shapes В32 GOST 1435-99, GOST 5210-95, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, TU 14-11-245-88, TU 14-1-1271-75
    Sheets and strips В33 GOST 4405-75
    Steel wire medium and high carbon В72 GOST 5468-88, GOST 9389-75

    Chemical composition

    Standard C S P Mn Cr Si Ni Fe Cu
    GOST 1435-99 0.65-0.74 ≤0.028 ≤0.03 0.17-0.33 ≤0.2 0.17-0.33 ≤0.25 Rest ≤0.25
    Fe is the basis.
    According to GOST 1435-99, the mass fraction of chromium, nickel and copper is indicated for 1 group of metal products. The mass fraction of sulfur in steel obtained by the electroslag remelting method should not exceed 0.013%. In the metal products of the third group, the mass fraction of Cr ≤ 0.20-0.40%, Ni ≤ 0.25%, Cu ≤0.25%. In metal products of the 1 st and 3 rd groups, made of steel obtained by scrap-process, the mass fractions of nickel, copper and chromium are increased by 0.05% of each element as compared to those in the table. In a metal designed for the manufacture of cold-rolled strip, an increase in the mass fraction of nickel, copper and chromium is not allowed.

    Mechanical properties

    Section, mm t отпуска, °C sT|s0,2, MPa σU, MPa d5, % d4 d y, % KCU, kJ/m2 HB, MPa
    Tape flatted average strength of 0.1-4.0 mm according to GOST 10234-77 in the state of delivery (indicated delivery)
    - - - 780-1270 - - - - - -
    - - - 780-930 - - - - - -
    - - - 930-1080 - - - - - -
    - - - 1080-1230 - - - - - -
    - - - ≤780 - - ≥10 - - -
    - - - ≤570 - - - - - -
    Annealed cold-rolled tape of the highest quality
    0.1-1.5 - - ≤650 - ≥15 - - - -
    Quenching in fine-grained structure with cooling in water + Vacation
    - 300 ≥1370 ≥1590 - - - ≥8 ≥310 -
    A sample with a diameter of 5 mm and a length of 25 mm deformed and annealed. A strain rate of 10 mm/min strain Rate 0,007 1/C
    - - - ≥105 ≥64 - - ≥90 - -
    Annealed cold-rolled tape of the highest quality
    1.5-4 - - ≤750 - ≥10 - - - -
    Quenching in fine-grained structure with cooling in water + Vacation
    - 400 ≥1180 ≥1270 - - - ≥11 ≥440 -
    A sample with a diameter of 5 mm and a length of 25 mm deformed and annealed. A strain rate of 10 mm/min strain Rate 0,007 1/C
    - - - ≥94 ≥65 - - ≥100 - -
    Quenching in fine-grained structure with cooling in water + Vacation
    - 500 ≥970 ≥1090 - - - ≥13 ≥730 -
    A sample with a diameter of 5 mm and a length of 25 mm deformed and annealed. A strain rate of 10 mm/min strain Rate 0,007 1/C
    - - - ≥63 ≥60 - - ≥100 - -
    Quenching in fine-grained structure with cooling in water + Vacation
    - 600 ≥830 ≥980 - - - ≥17 ≥930 -
    A sample with a diameter of 5 mm and a length of 25 mm deformed and annealed. A strain rate of 10 mm/min strain Rate 0,007 1/C
    - - - ≥36 ≥62 - - ≥100 - -
    - - - ≥22 ≥65 - - ≥100 - -
    - - - ≥17 ≥92 - - ≥100 - -
    Annealing
    - - - - ≥26 - - ≥71 - -
    - - - - ≥65 - - ≥99 - -
    Cold-rolled steel strip sagatovna (specified strength class)
    0.1-4 - - 750-900 - - - - - -
    Annealing
    - - - - ≥58 - - ≥98 - -
    Cold-rolled steel strip sagatovna (specified strength class)
    0.1-4 - - 900-1050 - - - - - -
    Annealing
    - - - - ≥59 - - ≥92 - -
    Cold-rolled steel strip sagatovna (specified strength class)
    0.1-4 - - 1050-1200 - - - - - -
    Annealing
    - - - - ≥38 - - ≥71 - -
    - - - - ≥45 - - ≥88 - -
    Annealing or normalizing
    - - - ≤690 ≥16 - - ≥30 - ≤200
    - - - ≤660 ≥13 - - ≥22 - ≤200
    - - - ≤640 ≥18 - - ≥20 - ≤200
    - - - ≤620 ≥22 - - ≥26 - ≤180
    - - - ≤460 ≥27 - - ≥34 - ≤155
    - - - ≤330 ≥33 - - ≥45 - ≤135
    - - - ≤205 ≥38 - - ≥60 - ≤110

    Description mechanical marks

    Name Description
    sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
    σU Limit short-term strength
    d5 Elongation after rupture
    d4 Elongation after rupture
    d Elongation after rupture
    y The relative narrowing
    KCU Toughness
    HB Brinell hardness number

    Physical characteristics

    Temperature r, kg/m3 l, W/(m · °C) R, Mr. · m С, J/(kg · °C)
    0 7830 46 130 -
    20 7830 46 130 -
    100 - 46 - -
    300 - 41 - 580
    600 - 33 - 970
    900 - 29 - 706
    400 - - - 664
    500 - - - 819
    700 - - - 710
    800 - - - 706
    1100 - - - 685

    A description of the physical symbols

    Name Description
    Е The normal elasticity modulus
    G Modulus of elasticity shear torsion
    r Density
    l Coefficient of thermal conductivity
    R UD. the resistivity
    a The coefficient of linear expansion
    С Specific heat

    Technological properties

    Name The value
    Weldability does not apply to welded structures.
    Склонность к отпускной хрупкости tend not
    The temperature of forging Start - 1180 °C, the end - of 800 °C. the cooling of the workpiece cross-section up to 100 mm in the air, 101-300 mm in the pit.
    Flock-sensitive sensitivity not sensitive
    Machinability In the annealed condition with HB 187 and blower SB=620 MPa Kn TV.SPL.=1.2 Kn b.St.=1.1
    Sanding behaviour good