STATO

  1. STATO 70
    Suzuki Garphyttan www.suzuki-garphyttan.com

    STATO 70

    Oil tempered SiCr-alloyed spring wire

    STATO 70 is especially intended for the manufacture of springs exposed to static or moderately high fatigue stresses. The material has good relaxation properties.

    The wire is manufactured in sizes from Ø 0.50 mm to 7.00 mm. Other wire sizes on request.

    Chemical composition

    C (%) Si (%) Mn (%) P max. (%) S max. (%) Cr (%)
    0.50 - 0.60 1.20 - 1.60 0.50 - 0.80 0.025 0.025 0.50 - 0.80

    Mechanical properties

    1) Other wire sizes on request.
    2) Ovality, i. e. the difference between the largest and smallest dimension of a cross section, is maximum half the tolerance range.
    3) Conversion from tensile strength to hardness values can be calculated in standard ISO EN 18265. The tensile strength Rm within one coil does not vary more than 70 N/mm2.

    For round wire

    Diameter (mm) Tolerance (± mm) Tensile Strength (N/mm²) Reduct. of area (min. %)
    0.50 - 0.80 0.010 2100 - 2300
    0.81 - 1.00 0.015 2100 - 2300 50
    1.01 - 1.40 0.020 2060 - 2260 50
    1.41 - 1.60 0.020 2040 - 2220 50
    1.61 - 2.00 0.025 2000 - 2180 40
    2.01 - 2.50 0.025 1970 - 2140 50
    2.51 - 2.70 0.025 1950 - 2100 50
    2.71 - 3.00 0.030 1910 - 2100 50
    3.01 - 3.50 0.030 1900 - 2060 45
    3.51 - 4.00 0.030 1870 - 2030 45
    4.01 - 4.50 0.035 1860 - 2020 45
    4.51 - 5.00 0.035 1830 - 1980 45
    5.01 - 5.60 0.035 1800 - 1950 40
    5.61 - 6.50 0.040 1780 - 1930 40
    6.51 - 7.00 0.040 1740 - 1890 35

    Yield point

    The proof stress Rp0.2 is min. 0.9 x tensile strength of the wire.

    Surface conditions

    Surface condition

    Surface condition – end sample test

    The wire is end sample tested by means of etch testing and binocular inspection as well as microscopical inspection of the material structure.

    Max. permissible depth of partial surface decarburization and surface defects, 1.5% x wire diameter. No complete decarburization allowed.

    Physical properties

    E and G modulus of elasticity

    206 kN/mm²

    kN/mm²

    E and G modulus of shear

    79.5 kN/mm²

    kN/mm²

    Recommendations

    Heat treatment

    As soon as possible after coiling, the springs should be stress relieved.

    Hot presetting

    After shot peening, the springs should be hot preset or stress relieved. In order to reach optimum fatigue and relaxation properties, the springs must be preset at an appropriate stress.

    Shot peening

    In order to obtain optimum fatigue properties, the process time should be adjusted to get a complete treatment. Size of shots should be adapted to wire dimension, pitch and shot peening equipment. Shot peening of the inside of the spring coils is particularly critical.

    Nearest equivalent steel grades

    EN FDSiCrV, SIS 142090-05

    Standards

    ASTM A401, BS 2803 685A55HS, JIS G3561 SWOSC-V

  2. STATO 75
    Suzuki Garphyttan www.suzuki-garphyttan.com

    STATO 75

    Oil tempered SiCrV-alloyed spring wire

    STATO 75 is especially intended for the manufacture of springs exposed to static or moderately high fatigue stresses. The material has good relaxation properties.

    The wire is manufactured in sizes from Ø 2.00 mm to 7.00 mm. Other wire sizes on request.

    Chemical composition

    C (%) Si (%) Mn (%) P max. (%) S max. (%) Cr (%) V (%)
    0.50 - 0.70 1.20 - 1.65 0.50 - 0.80 0.025 0.025 0.50 - 1.00 0.05 - 0.20

    Mechanical properties

    For round wire

    Diameter (mm) Tolerance (± mm) Tensile Strength (N/mm²) Reduct. of area (min. %)
    2.00 - 2.50 0.020 2110 - 2210 45
    2.51 - 3.20 0.020 2060 - 2160 45
    3.21 - 4.00 0.025 2010 - 2110 45
    4.01 - 5.00 0.025 1960 - 2060 45
    5.01 - 5.60 0.030 1910 - 2010 40
    5.61 - 6.50 0.035 1910 - 2010 40
    6.51 - 7.00 0.035 1860 - 2010 40

    Yield point

    The proof stress Rp0.2 is min. 0.9 x tensile strength of the wire.

    Surface conditions

    Surface condition

    Surface condition – end sample test
    The wire is end sample tested by means of etch testing and binocular inspection as well as microscopical inspection of the material structure.

    Max. permissible depth of partial surface decarburization and surface defects, 1.5% x wire diameter. No complete decarburization allowed.

    Physical properties

    E and G modulus of elasticity

    About 206 kN/mm2

    kN/mm²

    E and G modulus of shear

    About 79.5 kN/mm2

    kN/mm²

    Recommendations

    Heat treatment

    As soon as possible after coiling, the springs should be stress relieved.

    Hot presetting

    After shot peening, the springs should be hot preset or stress relieved. In order to reach optimum fatigue and relaxation properties, the springs must be preset at an appropriate stress

    Shot peening

    In order to obtain optimum fatigue properties, the process time should be adjusted to get a complete treatment. Size of shots should be adapted to wire dimension, pitch and shot peening equipment. Shot peening of the inside of the spring coils is particularly critical.

    Nearest equivalent steel grades

    EN FDSiCrV

    Standards

    EN 10270-2