Selecting the right mold steel directly affects mold lifespan, part quality, and production cost. Here is a practical comparison of the most common mold steel grades used in injection mold manufacturing.
1. P20 Tool Steel
P20 is a pre-hardened steel delivered at 28-32 HRC. It is the most commonly used grade for general-purpose injection molds, offering good machinability and toughness at a budget-friendly cost. It is ideal for low to medium volume production up to 300,000 cycles.
2. NAK80
NAK80 is a premium pre-hardened steel with 38-42 HRC hardness. It offers excellent polishability for mirror finishes and superior dimensional stability, making it a popular choice for high-cavity molds and optical applications. It can achieve 500,000 to 1 million cycles.
3. S136 Stainless Steel
S136 (1.2083) is a martensitic stainless steel with 48-52 HRC hardness after heat treatment. Its excellent corrosion resistance makes it the go-to grade for medical devices, food-contact parts, and molds processing corrosive materials. Expect 1 million+ cycles with proper maintenance.
Choosing the Right Steel for Your Project
Consider production volume, the material being molded, surface finish requirements, and budget when selecting mold steel. RCH Plastic’s engineering team can help you choose the optimal steel grade for your specific application.
Selecting the right material for your precision mold and tool is essential. Our engineers help you choose the optimal steel grade for long-lasting precision mold and tool performance.