Huaxia Steel — Professional Plastic Mold Tool Steel Supplier
15+ years of experience | ISO 9001 & SGS Certified | Factory-direct pricing | Custom sizes available | Worldwide shipping
What is P20 TOOL STEEL?
AISI P20 tool steel is a pre-hardened chromium-molybdenum alloy mold steel specifically developed for the plastic injection molding industry. Supplied at a ready-to-use hardness of 28-34 HRC, P20 eliminates the distortion risks and delays associated with post-machining heat treatment. Its uniform through-hardness in large sections, combined with excellent polishability and good machinability, has made P20 the most widely used plastic mold steel worldwide.
Huaxia Steel supplies premium P20 mold steel conforming to ASTM A681, DIN 1.2311 / 1.2738, and GB 3Cr2Mo standards. We offer P20 in large pre-hardened plates, forged die blocks, and round bars—all ultrasonically tested and certified.
Need P20 TOOL STEEL for Your Project?
We offer custom sizes, competitive pricing, and fast global delivery.
Chemical Composition (wt%)
| Element | Min (%) | Max (%) |
|---|---|---|
| Carbon (C) | 0.28 | 0.40 |
| Silicon (Si) | 0.20 | 0.80 |
| Manganese (Mn) | 0.60 | 1.00 |
| Phosphorus (P) | — | 0.030 |
| Sulfur (S) | — | 0.030 |
| Chromium (Cr) | 1.40 | 2.00 |
| Molybdenum (Mo) | 0.30 | 0.55 |
Data per ASTM A681 / equivalent standards (2025/2026 Reference).
Mechanical & Physical Properties
- Hardness (Pre-hardened, as-supplied): 28-34 HRC
- Tensile Strength: 965-1,100 MPa
- Yield Strength (0.2%): 850-950 MPa
- Elongation: 15-18%
- Density: 7.85 g/cm³ (0.284 lb/in³)
- Elastic Modulus: 207 GPa (30,000 ksi)
- Thermal Conductivity (20°C): 34 W/m·K
- Polishability: Excellent (up to SPI A-1 mirror finish achievable)
Heat Treatment Guide
| Process | Temperature | Details |
|---|---|---|
| As-Delivered Condition | Pre-hardened | 28-34 HRC; ready for machining and use without additional heat treatment |
| Stress Relieving | 480-550°C (900-1020°F) | After heavy machining; 1 hr per 25mm thickness; slow cool |
| Flame/Laser Hardening (optional) | 850-880°C (1560-1616°F) | Surface hardening of wear areas; air cool; temper at 180-200°C |
| Nitriding (optional) | 510-525°C (950-980°F) | Case hardness: 650-700 HV; case depth: 0.30-0.50mm |
| Re-Hardening (if needed) | 830-870°C (1525-1600°F) | Oil quench; temper at desired range (not typical for P20) |
Need Custom Heat Treatment Advice?
Our engineers can recommend optimal heat treatment parameters for your specific application.
Common Applications
- Injection mold cavities & cores (large to medium)
- Blow molding dies
- Compression & transfer molds
- Die casting die holders & frames
- Structural mold bases & plates
- Extrusion dies for plastics & rubber
- Thermoforming molds
- Shoe sole molds
International Equivalent Grades
| Standard / Country | Grade Designation | Details |
|---|---|---|
| USA (AISI/SAE) | P20 | UNS T51620, ASTM A681 |
| Germany (DIN) | 1.2311 / 1.2738 | 40CrMnMo7 / 40CrMnNiMo8-6-4 |
| EU (EN ISO) | 40CrMnMo7 | EN ISO 4957 |
| Japan (JIS) | — | PDS-3, NAK80 (Daido); HPM2 (Hitachi) |
| China (GB) | 3Cr2Mo | GB/T 1299; also 718H (P20+Ni variant) |
| Sweden (ASSAB) | 618 | ASSAB 618 / 718 |
Available Forms & Dimensions
Plates (thickness 10-500mm, width up to 2500mm), Forged die blocks up to 2000x1500mm, Round bars (dia 20-600mm), Pre-machined 6-sided blocks available
Custom sizes: Available upon request. Contact us with your specifications for a tailored quotation.
Why Choose Huaxia Steel as Your P20 TOOL STEEL Supplier?
Factory-Direct Pricing
Eliminate middlemen. Our direct mill partnerships ensure competitive pricing on every order, from small prototype quantities to container loads.
Certified Quality
Every shipment includes full mill test certificates (MTC/EN 10204 3.1). ISO 9001 certified. Third-party SGS inspection available on request.
Custom Processing
Cut-to-size, precision sawing, surface grinding, and heat treatment services. We deliver material ready for your production line.
Fast Global Logistics
Efficient shipping to North America, Europe, Middle East, Southeast Asia, and beyond. Standard lead time 7-15 days for stock items.
Frequently Asked Questions
Q: What is the maximum hardness achievable with P20 tool steel?
The maximum hardness depends on the specific grade. After proper heat treatment, typical maximum hardness ranges from 58-67 HRC. Refer to the heat treatment table above for specific tempering curves.
Q: Can P20 tool steel be welded?
Most tool steels can be welded for repair purposes, but it requires proper preheating, low-hydrogen electrodes, and post-weld heat treatment. For high-chromium grades like D2, welding is generally not recommended for structural applications. Always consult the manufacturer’s welding guidelines.
Q: What is the difference between P20 and other tool steel grades?
Each tool steel grade is optimized for specific applications. The key differentiators are wear resistance, toughness, hot hardness, and heat treatment method (air/oil/water). Compare grades based on your specific requirements: wear resistance (D2 > A2 > O1), toughness (S7 > H13 > A2), and hot hardness (M2 > H13 > D2).
Q: How do I order P20 tool steel from Huaxia Steel?
Simply contact us via the form on this page, email, or phone. Provide the grade, dimensions (thickness x width x length or diameter x length), quantity, and any special requirements such as surface finish or heat treatment condition. Our team will respond with a tailored quotation within 12 hours.
Q: What certifications do your tool steel products carry?
All Huaxia Steel tool steel products are supplied with full Mill Test Certificates (MTC/EN 10204 3.1) showing chemical composition and mechanical properties. We are ISO 9001:2015 certified, and third-party inspection (SGS, BV, TUV) is available upon request at no extra charge for orders above 5 tons.
Ready to Order P20 TOOL STEEL?
Factory-direct pricing. ISO & SGS certified quality. Fast global logistics. Get your quote in 12 hours.




