42CrMo steel belongs to ultra-high-strength steel. It has high strength and toughness, and good hardenability. No obvious temper brittleness. After quenching and tempering treatment, it has a higher fatigue limit and resistance to multiple impacts. Good low-temperature impact toughness.
42CrMo steel Worldwide Equivalents
country / region
China
EU
Germany
Japan
France
England
USA
Standard
GB
EN
DIN,WNr
JIS
AFNOR
BS
–
Grade
42CrMo
42CrMo4 (1.7225)
42CrMo4
SCM440H
42CD4
708M40 CFS11
4140 4142
country / region
Italy
Spain
Finland
Russia
Inter
Sweden
Standard
UNI
UNE
SFS
GOST
ISO
SS
Grade
42CrMo4
40CrMo4 F1252
K100
35KHM 38KHM
42CrMo4
2244
Chemical Composition
C
Si
Mn
P
S
Cr
Mo
0.38 to 0.45
0.17 to 0.37
0.50 to 0.80
≤ 0.030
≤ 0.030
0.90 to 1.20
0.15 to 0.25
Mechanical Properties
Yield strength: ≥ 930 MPa
Tensile strength: ≥ 1080 MPa
Elongation: ≥12%
Rate of reduction in area: ≥45%
Impact absorbing energy: ≥ 63 J
Material Brinell hardness: ≤229 (Annealed or high temperature tempered steel rod)
Sample diameter: 25mm
Physical properties of 42CrMo steel
Critical temperature
Critical point
Ac1
Ac3
Ms
Temperature/℃
730
800
310
Expansion coefficient
Temperature/℃
20~100
20~200
20~300
20~400
20-500
20-600
Expansion coefficient/℃-1
11.1×10K
12.1×10K
12.9×10K
13.5×10K
13.9×10K
14.1×10K
Thermal conductivity
Temperature/℃
20
300
400
500
600
Coefficient of thermal conductivity
210000MPa
185000MPa
175000MPa
165000MPa
15500oMPa
Heat treatment
First quenching heating temperature: 850 ℃(Cooling – oil)
High strength and hardenability. Good toughness, small deformation during quenching. High creep strength and lasting strength at high temperature.
It is used to manufacture forgings that require higher strength and larger quenched and tempered section than 35CrMo steel. Such as large gears for locomotive traction. Supercharger transmission gears, pressure vessel gears. Rear axles, connecting rods and spring clips under heavy load .
It can be used for drill pipe joints and fishing tools in oil wells below 2000m.
Dies that can be used for bending machines.
Available Size
Round Bar
Diameter(mm): 6-800mm ,Length: 1000-9000mm or custom size
Plate/Flat/Block
Thickness: 6mm-500mm , Width: 20mm-1000mm or custom size
