20Cr is a low hardenability carburized steel. Most of them are used to manufacture carburized parts with high core strength requirements, surface wear, section less than 30mm or complex shape and low load.
Worldwide equivalents of grade 20Cr
|country / region||China||USA||Germany||Japan||Inter|
Chemical Composition (%) of 20Cr Steel Material:
|C||Si||Mn||Cr||P ≤||S ≤||Cu ≤||Ni ≤||Mo ≤|
|0.18 – 0.24||0.17 – 0.37||0.50- 0.80||0.70 – 1.00||0.03||0.03||0.03||0.03||0.03|
Mechanical Properties of 20Cr Steel:
Tensile strength: ≥835 N/mm2
Yield strength: ≥540 N/mm2
Elongation after break: ≥10%
Rate of reduction in area: ≥40%
Impact absorbing energy: ≥47 J
Material Brinell hardness: ≤179 (annealing or high temperature tempering state)
Test sample size: 15mm
First quenching heating temperature: 880 °C ,Cooling: oil or water
Second quenching heating temperature: 780-820 °C ,Cooling: oil or water
Tempering heating temperature: 200 °C,Cooling: water or air
It has good comprehensive mechanical properties after quenching and low temperature tempering: good low temperature impact toughness and temper brittleness is not obvious.
20Cr steel has good weldability, and generally does not require heat treatment after welding, but parts with a thickness greater than 15mm need to be preheated to 100-150 °C before welding, and tempering heat treatment may not be performed after welding.
20Cr steel has higher strength and hardenability. But the toughness is poor. Under the condition of high temperature normalizing or quenching and tempering, the machinability is good, but the machinability after annealing is poor.
20Cr Steel Application
1. 20Cr steel is mostly used to manufacture carburized parts (oil quenching) with high core strength requirements, surface wear resistance, section less than 30mm or complex shape and low load, such as:
Machine tool gearbox gear, gear shaft, cam, worm, piston pin, claw clutch, etc;
For parts with small heat treatment deformation and high wear resistance, high-frequency surface quenching shall be carried out after carburizing, such as gears, shafts and spline shafts with modulus less than 3;
2. This steel can also be used in the quenched and tempered state to manufacture parts with high working speed and bearing medium impact load. This steel can also be used as low-carbon martensite quenching steel to further increase the yield strength and tensile strength of the steel.
|Round Bar||Diameter(mm): 6-800mm ,Length: 1000-9000mm or custom size|
|Plate/Flat/Block||Thickness: 6mm-500mm , Width: 20mm-1000mm or custom size|
|Tolerance||±1%，Thickness: +/-0.02mm, Width:+/-2mm|