Home > Injection Molding > Selection Guide for Mold Steel
Mold steel can be divided into three categories according to its working conditions: cold work mold steel, hot work mold steel and plastic mold steel. It has excellent strength, hardness, wear resistance and toughness. The most representative ones include P20, 718, S136, 45# steel, etc.

How many materials ?
Choose your Mold Steel Materials
BOOLING has extremely high requirements for the performance of mold steel and provides high-performance, high-quality mold solutions for various industries to meet mechanical strength, thermal management efficiency, surface integrity and environmental adaptability. The material verification system we have established includes 23 key performance indicator tests to ensure that each batch of materials meets aviation-grade standards.
BOOLING innovatively proposed a “material matching model” in the field of mold manufacturers. The model realizes the intelligent selection of high-performance steel through the coordinated operation of three modules: material database (covering 286 types of mold steel certified in 37 countries around the world), working condition simulation system and cost optimization algorithm.
Key factors in determining Mold Steel materials
Mold Steel material reference table
Booling has launched the production concept of “transparency of all-factor costs”. We believe that true cost control should be based on a deep understanding of the microstructure of the material. For example, in the application of P20 steel, we use efficient programming technology to shorten the rough processing time by 18%; in the S136 stainless steel processing link, the gradient heat treatment process makes the surface hardness distribution more reasonable and reduces the frequency of mold repair by 40%.
Mold Type | Representative Grades | Key Performance Metrics | Target Industries | Typical Applications | Material Selection Rationale |
---|---|---|---|---|---|
Cold Work Steel | Cr12MoV (D2) |
Hardness: HRC 58-62 Wear Res.: ≥800 HV Toughness: ≥20 J/cm² |
Automotive/Metalworking |
Precision stamping dies Progressive dies |
1. Deep hardenability (high C/Cr) 2. Cost-effective for mid-volume production 3. Meets 80% stamping wear requirements |
SLM-5 |
Hardness: HRC 60-62 Toughness: 65 J/cm² Isotropy: >90% |
Aerospace/Precision Eng. |
High-strength blanking dies Turbine blade forms |
1. 3× higher toughness 2. 400% longer edge-life 3. Ultra-low S/P (≤0.001%) |
|
Hot Work Steel | H13 |
Red Hardness: HRC≥45@600°C Thermal Fatigue: >5k cycles Thermal Cond.: 28 W/m·K |
Die casting/Forging |
Al die-cast molds Engine block molds |
1. Vanadium enhances thermal stability 2. Global benchmark (60% market share) 3. Optimal thermal crack resistance |
SRM-102 |
Red Hardness: HRC≥48@650°C Service Life: >200k shots |
New Energy Vehicles |
E-motor housings Mega casting dies |
1. Coating-compatible surface 2. 3× better molten Al resistance vs. H13 3. Superior hardenability (Ø800mm+) |
|
Plastic Mold Steel | P20 |
Pre-hard: HRC 30-35 Machinability: Ra≤0.8μm Cost: $5-6/kg |
Consumer Goods |
Toy housings Container molds |
1. Direct machining (no HT) 2. 60% lower machining cost/hour 3. Ideal for <500k shots |
S136 |
Corrosion Res.: 13% Cr Polishability: Ra≤0.01μm Hardness: HRC 48-52 |
Medical/Optics |
Light guide plates Medical tubes Lens molds |
1. Resists PVC chloride corrosion 2. Eliminates part hazing 3. FDA/EU food-contact compliant |
|
NAK80 |
Aged Hardness: HRC 40-45 Distortion: <0.02% Life: >3M shots |
Electronics |
SIM trays USB-C connectors |
1. Zero-distortion aging 2. Micro-hole accuracy ±0.003mm 3. 40% lower TCO vs. P20 |
|
Specialty Steel | CALMAX® 635 |
Antibacterial: >99.9% Polish: Ra 0.02μm Toughness: 50 J/cm² |
Medical Devices |
Insulin pen molds Surgical tools |
1. Martensitic stainless base 2. ISO 13485 certified 3. Prevents biofilm contamination |
STAVAX ESR |
Polish Grade: A1 Hardness: HRC 52-54 Purity: Ultra-high |
Optics/Luxury |
Camera lens molds Watch glass |
1. Sulfide-free structure 2. Optical-grade surfaces 3. Nano-etching resolution: 0.1μm |
Other metal materials reference table
BOOLING not only has hundreds of mold steel materials, but also provides you with different metal materials, such as cemented carbide, aluminum alloy, copper alloy, etc. In the production process of the mold, the mold material needs to be produced and processed under high temperature and high pressure, and always maintained a stable state to ensure the molding quality of the final product. We regard the accuracy of material matching as a key link in mold development.