There are many kind of steel, for long runs production, a durable mold is required, the tool steel must be selected properly, for small volume production, steel selection can be as economic as possible as long as it meet the requirement of production demands.

How to choose the injection mold steel? Important steel properties include:

• Ease of machining
• Dimensional stability after heat treatment
• Wear resistance
• Surface finish
• Corrosion resistance

Mold steel we selected frequently are 1.2344, 1.2343, 1.2312, 1.1730, H13, S136, 2083, etc. Normally we categorized them as preharden steel or harden steel, preharden steel can be machined and used directly after purchase, harden steel required heat treatment during process, the machining take longer time, injection mold made by harden steel usually have long service life.

Corrosion resistant hardened steels should be selected when conventional flame retardants are used. In the case of halogen free flame retardant DSM thermoplastics, standard steel types can be selected. Beryllium copper inserts may be used for improved cooling near hot spots. High heat conductivity is also required for gate drops in hot runner molds. Standardization of mold parts is growing, not only for ejector pins, leader pins and bushings, but also for mold plates and even complete mold bases. These standard mold bases require only machining of the cores, cavities and cooling channels and fitting of an ejection system. Advantages are:

• Cost savings 3050%
• Short delivery times
• Interchangeability
• Easy and rapid repair