SCM440 1.7225 4140
SCM440 1.7225 4140 General cold work die steel with good machinability,to be made die casting mold,extrusion and injection mold and ejector pins,ejector sleeve,punches,block gauge,measuring tools.
High wear resistance,high toughness,small deformation caused by heat treatment.
Have a high and uniform hardness after heat treatment,heat resisting,resistance to high temperature oxidation,good toughness,machinability and weldability.
Annealing ≤HB229,pre-hardened HRC 26-32.
General Information:
Chromium molybdenum high tensile steel with yield strength of 550N/mm2.
Chromium renders steel oil hardenable and increase hardenability.
Weldability suffers with increasing chromium content.
High temperature strength and high pressure hydrogenation properties are promoted by chromium and molybdenum.
Molybdenum significantly reduces temper brittleness.
Delivery condition:
cold drawn round bar/ QT round bar
Comparable Standards:
AISI/SAE | DIN | W.Nr. | JIS |
4140 | 42CrMo4 | 1.7225 | SCM440 |
Chemical Analysis (%):
C | Mn | Si | Cr | Mo | P | S |
0.38-0.45 | 0.60-0.90 | 0.15-0.40 | 0.90-1.20 | 0.15-0.30 | ≤0.035 | ≤0.035 |
Hot work and Heat treatment temperatures:
Forging | Normalization | Subcritical annealing | Isothermal annealing | Hardening | Tempering |
1100~900 | 860~880 | 680~720 | 830~900 | 830~860 oil | 550~650 |
Machanical Properties:
Tensile str. (N/mm2) | Yield point (N/mm2) | Elongation (%) | Contraction (%) | Impack work (J/cm2) | Hardness (HB) |
1080 | 930 | 12 | 45 | 63 | 217 |
Delivery Specification and Technical Condition
Coil
Size mm | Tolerance mm | Ovality mm |
Φ1.5-Φ3.0 | ±0.01 | ≤0.01 |
Φ3.1-Φ6.0 | ±0.015 | ≤0.015 |
Φ6.1-Φ16.0 | ±0.018 | ≤0.018 |
Φ16.1-Φ20.0 | ±0.02 | ≤0.020 |
Φ20.1-Φ25.0 | ±0.03 | ≤0.030 |
Cold Drawing Round Bar
Size mm | Tolerance mm | Straightness mm/m | Ovality mm |
Φ2.0-Φ4.0 | ±0.01 | ≤0.50 | ≤0.01 |
Φ4.1-Φ6.0 | ±0.015 | ≤0.70 | ≤0.015 |
Φ6.1-Φ13.0 | ±0.02 | ≤0.70 | ≤0.02 |
Φ13.1-Φ18.0 | ±0.025 | ≤0.70 | ≤0.025 |
Φ18.1-Φ25.0 | ±0.030 | ≤0.70 | ≤0.03 |
Φ25.1-Φ50.0 | ±0.05 | ≤0.70 | ≤0.05 |
Centerless Grinding Round Bar (Annealing condition)
Size mm | Tolerance mm | Straightness mm/m | Ovality mm |
Φ2.0-Φ4.0 | ±0.01 | ≤0.50 | ≤0.01 |
Φ4.1-Φ6.0 | ±0.01 | ≤0.50 | ≤0.01 |
Φ6.1-Φ13 | ±0.01 | ≤0.50 | ≤0.01 |
Φ13.1-Φ18.0 | ±0.015 | ≤0.50 | ≤0.015 |
Φ18.1-Φ25.0 | ±0.015 | ≤0.50 | ≤0.015 |
Φ25.1-Φ35.0 | ±0.02 | ≤0.50 | ≤0.02 |
Φ35.1-Φ50.0 | ±0.03 | ≤0.50 | ≤0.03 |
Centerless Grinding Round Bar (Pre-hardened condition)
Size mm | Tolerance mm | Straightness mm/m | Ovality mm |
Φ1.5-Φ4.0 | ±0.01 | ≤0.50 | ≤0.01 |
Φ4.1-Φ6.0 | ±0.01 | ≤0.50 | ≤0.010 |
Φ6.1-Φ13.0 | ±0.01 | ≤0.50 | ≤0.01 |
Φ13.1-Φ18.0 | ±0.015 | ≤0.50 | ≤0.015 |
Φ18.1-Φ25.0 | ±0.015 | ≤0.50 | ≤0.015 |
Φ25.1-Φ35.0 | ±0.02 | ≤0.50 | ≤0.02 |
Φ35.1-Φ50.0 | ±0.03 | ≤0.50 | ≤0.03 |
Peeling Round Bar
Size mm | Tolerance mm | Straightness mm/m | Ovality mm |
Φ5.0-Φ13.0 | ±0.04 | ≤0.60 | ≤0.04 |
Φ13.1-Φ20.0 | ±0.04 | ≤0.70 | ≤0.04 |
Φ20.1-Φ35.0 | ±0.5 | ≤0.70 | ≤0.05 |
Φ35.1-Φ60.0 | ±0.06 | ≤0.80 | ≤0.06 |
Φ60.1-Φ80.0 | ±0.07 | ≤0.80 | ≤0.07 |
Φ80.1-Φ120.0 | ±0.08 | ≤1.00 | ≤0.08 |
Delivery hardness
annealed condition ≤255HB
QT condition: 28-32HRC or as per customer requirement
<img src="https://img.waimaoniu.net/2326/2326-202104251003154352.jpg" style="width: 800px;" width="800" border="0" vspace="0" title="pre-hardened 26-32HRC 4140""/>