45B, alloy structural steel.

     Unified digital code: A70452

[] Chemical composition (mass fraction) (%)

C: 0.42 ~ 0.49

Si: 0.17 ~ 0.37

Mn: 0.60 ~ 0.90

B: 0.0005 ~ 0.0035

[] 45B alloy mechanical properties of structural steel
      Blank sample size (mm): 25

Heat treatment: the first quenching temperature (℃): 840; coolant: water

Second quenching temperature (℃): -

Tempering heating temperature (℃): 550; coolant: water

  Tensile strength (σb / MPa): ≧ 835

  Yield point (σs / MPa): ≧ 685

  Elongation (δ5 /%): ≧ 12

Reduction of (ψ /%): ≧ 45

    Impact absorbed energy (Aku2 / J): ≧ 47

Brinell hardness (HBS100/3000) (annealing or tempering condition): ≦ 217

   Key Features] [45 more steel this steel has high hardness, strength, wear resistance and hardenability, quenching in water, the critical diameter of 17 ~ 30mm, the critical quenching in oil diameter of 7 ~ 15mm.

[Application Example] usually used in the quenched state, for the manufacture of steel cross-section larger than 45, higher parts; such as the crank handle tractors and other similar parts. In addition, the manufacture of small size, less demanding parts, can replace 40Cr steel.