40CrMnMo 
 40CrMnMo, the Chinese national standard [1] of an alloy structural steel grades. Uniform digital code: A34402. 
 Chemical composition 
 Mass fraction (%): C: 0.37 ~ 0.45 Si: 0.17 ~ 0.37 Mn: 0.90 ~ 1.20 Cr: 0.90 ~ 1.20 
 40CrMnMo 
 Mo: 0.20 ~ 0.30 
 Mechanical Properties 
 【Size】 25mm blank sample 
 [Heat] quenching temperature (℃): 850; Coolant: Oil-tempered heating temperature (℃): 600; coolant: water, oil, mechanical properties] [tensile strength (σb / MPa): ≧ 980 yield point ( σs / MPa): ≧ 785 Elongation (δ5 /%): ≧ 10 section shrinkage (ψ /%): ≧ 45 impact absorbed energy (Aku2 / J): ≧ 63 Brinell hardness (HBS100/3000) ( annealing or tempering state): ≦ 217 
 Key Features 
 After quenching with good mechanical properties, good hardenability, temper resistance is higher. Mostly used in the quenched state [2]. Edit this paragraph Application example 
 Commonly used in the manufacture of heavy, large cross-section of the gear shaft, gear, the truck's rear axle axle, shaft, eccentric shafts, connecting rods, turbine-like parts can also replace the 40CrNiMo use.