ML20MnVB Cold Heading Steel Bar
ML20MnVB is cold forging steel forming steel, cold forging is used at one or more impact loads at room temperature, widely used in the production of screws, pins, nuts and other standard parts. The cold crucible process can save raw materials and reduce costs.
Moreover, cold work hardening can improve the tensile strength of the work piece and improve the performance. The steel used for cold crucible must have good cold upset performance, and the content of S and P in steel should be reduced.
The surface quality of steel is strict, and high-quality carbon steel is often used. If the carbon steel content of steel is more than 0.25%, the ball annealing heat treatment should be carried out to improve the cold heading performance of the steel.
Chemical composition(mass fraction)(wt.%) of the ML20MnVB:
C(%) | Si(%) | Mn(%) | P(%) | S(%) | Cr(%) | V(%) | B(%) | Al(%) |
---|---|---|---|---|---|---|---|---|
0.19-0.24 | Max 0.30 | 1.20-1.60 | 0.035 | 0.035 | — | 0.07-0.12 | 0.0005-0.0035 | 0.02 |
Mechanical properties of grade ML20MnVB:
Yield Rp0.2(MPa) | Tensile Rm(MPa) | Impact KV (J) | Elongation A (%) | Reduction in cross section on fracture Z (%) | As-Heat-Treated Condition | HBW |
---|---|---|---|---|---|---|
826 (≥) | 239 (≥) | 24 | 32 | 32 | Solution and Aging, Annealing, Ausaging, Q+T, etc | 121 |
Physical properties of grade ML20MnVB:
Property | Density kg/dm3 | Temperature T °C/F | Specific heat J / kgK | Thermal conductivity W/mK | Electric resistance µΩ·cm |
---|---|---|---|---|---|
161 (≥) | 957 (≥) | 13 | 23 | 33 | Solution and Aging, Annealing, Ausaging, Q+T, etc |
Temp. °C/°F | Creep strain limit (10000h) (Rp1,0) N/mm2 | Creep rupture strength (10000h) (Rp1,0) N/mm2 | - | - | - |
462 | 172 | 469 | - | - | - |