AISI P20 • DIN 1.2311 • SCM4 Steel
- What is P20 Steel?
- P20 Steel Grade Equivalent Chart
- P20 Steel Chemical Composition and Equivalent Grades
- 1.2311 Steel Physical Properties
- P20 Steel Mechanical Properties
- The Method of Use
- 1.2311 Tool Steel Forging
- P20 Steel Heat Treatment
- 1.2311 Steel Quality Certificate
- P20 Steel Application
- P20 Steel Supply
What is P20 Steel?
P20 steel has many excellent properties. In the pre-hardened status, the mold can be processed without any heat treatment. Which cut down the running period and improves efficiency. And it also is called DIN 1.2311 and SCM4 steel. After it has been processed through the forged, 1.2311 steel becomes dense. Then it can pass 100% ultrasonic test. And after the test, there will be no pores left and no defect. P20 tool steel chemical composition and more information as below.
P20 Steel Grade Equivalent Chart
| Country | USA | Germany/UK/France | ISO |
|---|---|---|---|
| Standard | ASTM A681-08 Alloy Tool Steel | EN ISO 4957: 1999 Tool Steel | ISO 4957: 1999 Tool Steel |
| Grades | P20 | 35CrMo7/1.2311 | 35CrMo7 |
P20 Steel Chemical Composition and Equivalent Grades
| STAND | C(%) | Mn(%) | P(%) | S(%) | Si(%) | Cr(%) | Mo(%) |
|---|---|---|---|---|---|---|---|
| ASTM A681-08 Alloy Tool Steel | 0.28-0.40 | 0.60-1.00 | ≤0.030 | ≤0.030 | 0.20-0.80 | 1.40-2.00 | 0.30-0.55 |
| EN ISO 4957: 1999 Tool Steel | 0.30-0.40 | 0.60-1.00 | - | - | 0.30-0.70 | 1.50-2.00 | 0.35-0.55 |
| ISO 4957: 1999 Tool Steel | 0.30-0.40 | 0.60-1.00 | - | - | 0.30-0.70 | 1.50-2.00 | 0.35-0.55 |
1.2311 Steel Physical Properties
| Density | Specific Gravity | Modulus of Elasticity | Thermal Conductivity | Machinability |
|---|---|---|---|---|
| 0.284 lb/in3(7861 kg/m3) | 7.86 | 30 x 106 psi(207 GPa) | 24 Btu/ft/hr/°F 41.5 W/m/°K | 60-65% of a 1% carbon steel |
P20 Steel Mechanical Properties
| Properties | Metric | Imperial |
|---|---|---|
| Hardness, Brinell(typical) | 300 | 33 |
| Hardness, Rockwell C(typical) | 30 | 30 |
| Tensile strength, ultimate | 965-1030 MPa | 140000-150000 psi |
| Tensile strength, yield | 827-862 MPa | 120000-125000 psi |
| Elongation at break(in 50 mm (2")) | 20.0% | 20.0% |
| Compressive strength | 862 MPa | 125000 psi |
| Charpy impact(V-Notch) | 27.1-33.9 J | 20.0-25.0 ft-lb |
| Poisson's ratio | 0.27-0.30 | 0.27-0.30 |
| Elastic modulus | 190-210 GPa | 27557-30457 ksi |
The Method of Use
1.2311 steel has been pre-hardened to 285-330HB(30-36HRC), which can be used directly for mold making and process. It also has the characteristics of good dimensional stability. Just Pre-hardened steel can meet the needs of the industry. The die life can reach 50W mode times.
1.2311 Tool Steel Forging
1.2311 steel plate and round bars materials are forged at 1093°C (2000°F) down to 899°C (1650°F). Forging below 871°C (1600°F) is not recommended for these steels P20 material.
P20 Steel Heat Treatment
Stress Relieving
Preheating: Because mold steel 1.2311 steel plate is sold in a pre-hardened condition, hardening heat treatment is not necessary. After machining and intermittently during service, the steel must be thermally stress relieved by heating to 900ºF (482ºC), equalizing and holding for one hour per inch (25.4mm) of thickness, and cooling in air to ambient temperature.
In those rare circumstances where the AISI steel P20 must be re-hardened, the steel must first be annealed prior to hardening.
Hardening
Critical Temperature: Ac1: 1405ºF (763ºC)
Preheating of P20 metal: Heat at a rate not exceeding 400ºF per hour (222ºC per hour) to 1150-1250ºF (621-677ºC) and equalize.
Austenitizing (High Heat)
Heat rapidly from the preheat to 1550ºF (843°C). Soak for 30 minutes for first inch (25.4mm) of thickness, plus 15 minutes for each additional inch (25.4mm).
Quenching
Pressurized gas, or interrupted oil to 150-125ºF (66-51ºC).
For oil, quench until black, at about 900°F (482°C), then cool in still air to 150-125°F (66-51°C).
Tempering
P20 tool steels are tempered at 482-593°C (900 to 1100°F) for a Rockwell C hardness of 37 to 28.
Annealing
Annealing for AISI P20 tool steels takes place at 760-788°C (1400 to 1450°F) and then the steels are cooled slowly in the furnace at a temperature less than 4°C (40°F) per hour.
1.2311 Steel Quality Certificate
P20 Steel Application
P20 steel is used to make thermoplastic molds, extrusion dies, injection molds and die casting dies. And can also be used to make main components of heavy-duty mold. In addition, it also be used to produce cold structural parts, TV cases, washing machines, inner casings of refrigerator and buckets. Of course, 1.2311 steel can also be used to make bumper dies for automobiles or structural components of cars. 1.2311 steel has very good hardness and plasticity. So it can be used to make a variety of molds.
P20 Steel Supply
Round Bar:
Specification: Dia 20-1000mm
Surface: Black, Rough Machined, Turned or as per given requirements.
Sheet/Plate/Slab:
Specification: thickness: 130-650mm; width: 205-2200mm
Surface: Black, Rough Machined, Turned or as per given requirements.
Block:
Specification: thickness: 130-650mm; width: 205-810mm
Surface: Black, Rough Machined, Turned or as per given requirements.
Notice:
We have our own cutting and processing equipment. Specifications can be cut and customized according to your requirements.
We specialize in special steel stockist and supplier with a high-quality stand for many years. Please contact us for any request of P20/1.2311 steels materials. Songshun Steel always with you.
