20Cr

Description

20Cr是一种低淬透性渗碳钢。大多用于制造心部强度要求较高,表面承受磨损、截面在30mm以下的或形状复杂而负荷不大的渗碳零件。

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 / regionChinaUSAGermanyJapanInter
StandardGBAISI SAE/ASTMDINJIS ISO
Grade20Cr5120-20Cr4ScR42020Cr3
 
 
 
Chemical Composition (%) of 20Cr Steel Material:
CSiMnCrP ≤S ≤Cu ≤Ni ≤Mo ≤
0.18 – 0.240.17 – 0.370.50- 0.800.70 – 1.000.030.030.030.030.03

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

Heat treatment:

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

Features

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钢大多用于制造心部强度要求较高,表面承受磨损、截面在30mm以下的或形状复杂而负荷不大的渗碳零件(油淬),比如:

机床变速箱齿轮、齿轮轴、凸轮、蜗杆、活塞销、爪形离合器等;

对热处理变形小和高耐磨性的零件,渗碳后应进行高频表面淬火,如模数小于3的齿轮、轴、花键轴等;

  • 此钢也可在调质状态下使用,用于制造工作速度较大并承受中等冲击负荷的零件,这种钢还可用作低碳马氏体淬火用钢,更进一步增加钢的屈服强度和抗拉强度。

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.

Available Size

Round BarDiameter(mm): 6-800mm ,Length: 1000-9000mm or custom size
Plate/Flat/BlockThickness: 6mm-500mm , Width: 20mm-1000mm or custom size
Tolerance±1%,Thickness: +/-0.02mm, Width:+/-2mm