In the field of high-precision, high-gloss plastic injection molds, NAK80 mold steel is known as the “mirror mold steel” due to its excellent polishability and stable performance. It is a pre-hardened plastic mold steel that can directly achieve mirror effect without complex polishing, which greatly improves production efficiency and reduces processing costs. This article will detail the core features, chemical composition, application scenarios and advantages of NAK80 mold steel, helping you understand why it is the first choice for high-gloss plastic molds.
Core Features of NAK80 Mold Steel
NAK80 is a pre-hardened plastic mold steel with unique performance, which is mainly reflected in the following aspects:
- Excellent Polishability: NAK80 has a uniform and dense structure, no impurities, and can easily achieve mirror polishing (Ra ≤ 0.01 μm) without secondary polishing. This is its biggest advantage compared with other plastic mold steels such as P20 and 718H.
- Pre-hardened Delivery: NAK80 is delivered in pre-hardened state, with a delivery hardness of 38-42 HRC, which can be directly processed without heat treatment, saving processing time and costs.
- Good Toughness & Wear Resistance: NAK80 contains nickel, chromium and other elements, which not only has good toughness but also has excellent wear resistance, ensuring the long service life of the mold.
- Corrosion Resistance: NAK80 has certain corrosion resistance, which can be used for molds processing general corrosive plastics (such as PC, ABS), and is not easy to rust during use.
- Stable Dimensional Accuracy: The structure of NAK80 is uniform, and the deformation during processing is small, which can ensure the dimensional accuracy of the mold and meet the requirements of high-precision plastic products.
Chemical Composition of NAK80 Mold Steel
The excellent performance of NAK80 is determined by its reasonable chemical composition. The following is the detailed chemical composition (mass fraction):
| Element | Content Range | Function |
| C (Carbon) | 0.15-0.25% | Improve hardness and wear resistance |
| Cr (Chromium) | 1.20-1.60% | Enhance corrosion resistance and polishability |
| Ni (Nickel) | 3.00-4.00% | Improve toughness and polishability |
| Mo (Molybdenum) | 0.20-0.40% | Refine grain, improve toughness |
Applications of NAK80 Mold Steel
Due to its excellent polishability and stable performance, NAK80 is mainly used in high-precision, high-gloss plastic injection molds, especially in industries with high requirements on product surface quality:
- Optical Industry: High-transparency plastic products such as PC/PMMA lenses, optical filters, and camera lenses. NAK80’s mirror polishing effect can ensure the transparency and surface smoothness of the product, avoiding light refraction errors.
- Cosmetic Packaging Industry: High-gloss cosmetic packaging such as lipstick tubes, perfume bottles, and foundation boxes. NAK80 can ensure the surface gloss of the product, making it more high-end and attractive.
- Electronic Industry: High-precision electronic product shells such as mobile phone cases, tablet cases, and laptop shells. NAK80’s stable dimensional accuracy and good polishability can meet the strict requirements of electronic products.
- Medical Industry: High-gloss medical device parts such as medical lenses, infusion set connectors. NAK80’s clean surface and good corrosion resistance can meet the high hygiene requirements of medical products.
Advantages of NAK80 Compared with Other Plastic Mold Steels
Compared with other common plastic mold steels (such as P20, 718H, S136), NAK80 has obvious advantages in polishability and processing efficiency:
| Mold Steel Grade | Polishability | Processing Efficiency | Corrosion Resistance |
| NAK80 | Excellent (mirror effect without secondary polishing) | High (pre-hardened, direct processing) | Good |
| P20 | General (mirror effect needs complex processing) | High (pre-hardened, direct processing) | Poor |
| 718H | Good (easy to achieve mirror effect) | High (pre-hardened, direct processing) | General |
| S136 | Excellent (mirror effect) | Low (needs heat treatment before processing) | Excellent |
Precautions for Using NAK80 Mold Steel
To maximize the performance of NAK80 and extend the service life of the mold, pay attention to the following points when using it:
- Processing Tools: Due to the high hardness of NAK80 (38-42 HRC), it is recommended to use high-speed steel or carbide tools for processing, and the cutting speed should be controlled appropriately to avoid tool wear.
- Polishing Process: Although NAK80 has excellent polishability, it is still necessary to use appropriate polishing tools and polishing paste during polishing to ensure the mirror effect.
- Maintenance: After using the mold, it should be cleaned in time to remove residual plastic and cleaning agent, and apply anti-rust oil to prevent rust during storage.
- Application Scope: NAK80 is not suitable for molds processing highly corrosive plastics (such as PVC), and S136 is recommended for such scenarios.
If you need to produce high-gloss, high-precision plastic products, NAK80 mold steel is your ideal choice. We provide high-quality NAK80 mold steel, pre-hardened delivery, with complete quality certificates and free custom cutting and processing services. Contact us now to get a free sample and detailed material data sheet!