High Quality Bearing steel 20NiCrMo7 1.high toughness and hardness 2.Diamensions:6mm-800mm 3.Length:normally or as request

(carburize )bearing steel:20NiCrMo7

1Characteristics and application scope:

       To heat treatment (is fire, annealed or high temperature tempering) or not heat treatment state delivery, delivery status should be indicated in the contract

2chemical composition:

C :0.17~0.23(allowable deviation:±0.02)Si:0.15~0.40(allowable deviation:±0.03)Mn:0.40~0.70(allowable deviation:±0.04)S :≤0.030(allowable deviation:+0.005)P :≤0.030(allowable deviation:+0.005)Cr:0.35~0.65(allowable deviation:±0.15)Ni:1.60~2.00(allowable deviation:±0.05)Cu:≤0.30(allowable deviation:+0.05)Mo:0.20~0.30(allowable deviation:±0.02)

3 mechanical property:

tensile strengthσb (MPa):≥980(100)

elongation     δ5 (%):≥13

relative reduction in area ψ (%):≥45

notched bar impact strength αkv (J/cm2):≥78(8)

size of sample:25mm

4Heat treatment standard and metallographic organization:

heat treatment regime: Quenching, first,880±20°C,second,800±20°C,oil cooling,temper,150~200°C, air cooling.

   metallographic organization: Carburized layers for high carbon martensite. The heart for low carbon martensite.

5condition of delivery:Hot-rolled steel forging system with hot or (forging) state or annealing state delivery. Cold pull steel to annealing state delivery.

20NiCrMo7 high quality bearing steel