AISI 1020 Carbon Steel | DIN 1.0402 | C22 | S20C

AISI 1020 steel is a low carbon steel which has at least 0.17%C and 0.3%Mn. It has a good combination of strength and ductility and can be carburized,but due to its low carbon content, it is difficult to induction hardening or flame hardening. Due to lack of alloying elements, it is not suitable for nitriding.AISI 1020 steel can be easily machined,and can be welded easily using all of the traditional methods.

AISI 1020 forged round bar

1.AISI 1020 steel Supply Form & Size

Form of SupplySize(mm)Length(mm)
Round barΦ6-Φ1,0003,000-10,000
Square bar100x100-600x6003,000-6,000
Plate/SheetThickness :20-400
Flat bar/BlcoksThickness :120-800

2.Surface Finish&Tolerance

Surface FinishBlack-Forged Black-Rolled Turned   GrindingPolishedPeeledCold Drawn
Tolerance(0,+5mm)(0,+1mm)(0,+3mm)Best h9Best h11Best H11Best H11

3.Chemical Composition&Related Specifications

10200.17-0.23≤ 0.40.30-0.60≤ 0.04≤ 0.05
C22/1.0402 EN3/070M2020#S20C

4.Mechanical Property

Tensile strength420 MPa60900 psi
Yield strength350 MPa50800 psi
Modulus of elasticity205 GPa29700 ksi
Shear modulus (typical for steel)80 GPa11600 ksi
Poisson’s ratio0.290.29
Elongation at break (in 50 mm)0.150.15
Hardness, Brinell121121
Hardness, Knoop (converted from Brinell hardness)140140
Hardness, Rockwell B (converted from Brinell hardness)6868
Hardness, Vickers (converted from Brinell hardness)126126
Machinability (based on AISI 1212 steel. as 100 machinability)6565

5.AISI 1020 steel Forging

Forging temperature:950-1200℃,air cooling after forging.


  1. Preheat AISI 1020 steel uniformly and slowly;
  2. Increase the temperature to  890°C – 940°C;
  3. Hold suitable time for the steel to be thoroughly heated,
  4. Cooled in air


  1. Heated temperature to 870°C – 910°C
  2. Hold suitable time for the steel to be thoroughly heated
  3. Cooled in a furnace.


  1. Heat the temperature between 880°C – 920°C
  2. Hold for sufficient time  in a suitable carburizing atmosphere
  3. Followed by refining/hardening and tempering processess

9.Core Refining

  1. Re-heat the temperature at 870°C – 900°C
  2. Hold until the temperature remains constant all over the section
  3. Quench in water, oil or brine.

10.Case Hardening

  1. Re-heat the temperature to 760°C – 780°C after Refining
  2. Holding until the temperature is consistent all over the section
  3. Quenched in water.


AISI 1020 steel can be largely utilized in all industrial sectors in order to enhance weldability or machinability properties. It is used in a variety of applications due to its cold drawn or turned and polished finish property.It is used for simple structural application such as cold headed bolts,and also used in the case hardened condition.