Guide to Steel Selection for Injection Medical Molds
2025/10/22 5

Injection medical molds, as crucial components in the manufacturing of medical devices, directly determine the quality and safety of the final medical products. Therefore, the selection of steel for manufacturing injection medical molds is of utmost importance. This article will provide a detailed introduction to several types of steel commonly used in injection medical molds and their characteristics.

I. SKD61 Steel

SKD61 steel is a special alloy steel, characterized by high hardness, high strength, high-temperature strength, and high heat resistance. It exhibits excellent heat resistance and thermal fatigue resistance at high temperatures, making it highly suitable for manufacturing medical injection molds. With a long service life, SKD61 steel is the preferred material for producing high-quality, high-precision injection molds.

II. SKD11 Steel

SKD11 steel is renowned for its superior cutting and machining performance, enabling the production of highly precise medical injection molds. It not only possesses high hardness and toughness but also boasts excellent wear resistance and corrosion resistance. These characteristics make SKD11 steel an ideal choice for manufacturing high-precision medical injection molds.

III. 718H Steel

718H steel is an improved mold steel based on P20 steel, outperforming P20 steel in terms of hardness, durability, and polishability. Despite its relatively high price, 718H steel is widely used in the manufacturing of medical injection molds due to its exceptional wear resistance, corrosion resistance, and high-temperature thermal stability. It is particularly suitable for manufacturing large and complex molds, meeting the requirements for high precision and stability in medical injection molds.

IV. 8407 Steel

8407 steel is a high-strength and high-toughness premium mold steel, primarily composed of elements such as carbon, silicon, manganese, cobalt, and molybdenum. It offers good machinability and wear resistance, making it suitable for manufacturing high-precision medical injection molds. The high strength and toughness of 8407 steel ensure the stability and durability of the mold during long-term use.

V. S136 Steel

S136 steel is a stainless mold steel with excellent corrosion resistance and polishability. After heat treatment, its hardness can reach over 58HRC. In humid environments and when in contact with corrosive materials, S136 steel is resistant to rusting and oxidation and can easily achieve a highly smooth surface. These characteristics make S136 steel highly suitable for manufacturing injection molds for transparent plastic products and medical plastic supplies.

VI. Considerations for Material Selection and Machining

When selecting steel for medical injection molds, it is essential to adhere strictly to technical specifications to ensure that the steel quality meets the manufacturing requirements of medical injection molds. Meanwhile, the machining requirements for medical injection molds are extremely high, as the material and quality of the steel directly affect the precision and lifespan of the mold. Therefore, strict rules and regulations must be followed during the machining process to ensure the machining accuracy and quality of the mold.

In addition, quality inspection is also a crucial step in ensuring the quality and safety of medical injection molds. In medical device production, the quality of the mold directly relates to the quality and safety of the products. Therefore, strict quality inspections must be conducted to ensure that the mold quality and durability meet the manufacturing requirements of medical products.

VII. Conclusion

In conclusion, the selection of steel for injection medical molds should comprehensively consider factors such as hardness, strength, wear resistance, corrosion resistance, and machinability. Steels like SKD61, SKD11, 718H, 8407, and S136 are all ideal choices for manufacturing high-precision medical injection molds. When selecting steel, the specific manufacturing requirements and working environment of the medical injection mold should be taken into account to ensure that the mold quality and performance meet the manufacturing requirements of medical products. Meanwhile, strict adherence to rules and regulations during the machining and use processes is necessary to ensure the quality and safety of medical devices.