Through-hardening plastic mold steels

Through-hardening plastic mold steels for hardening after (pre-)machining, e.g. for molds and tools subject to high wear (hardness range 44 to 62 HRC)... 

The material 1.2738 is the material most often used for larger molds. For best graining results, this steel was further developed and is now available as 2738 mod. TS. Other quenched and tempered steels are 1.2311,1.2711, and 1.2316 as a corrosion resistant material. For small molds or as mold inserts with high hardness, through hardened plastic mold steels such as 1.2343,1.2344, and 1.2767 can be used. 1.2083 is available as a corrosion-resistant variant. 

FIGURE 3.6 Comparison of the through-hardenability of pre-hardened plastic mold steels... 

FIGURE 3.9 Abrasive wear resistance as a function of carbide size and of the carbide content of the corrosion-resistant plastic mold steels compared to through-hardening... 

There may be a requirement for surface finish, molded-in color, textured surface, or other conditions the plastic material is to meet (Chapter 2). The different processes may be able to provide only one surface to be smooth or both sides are smooth. Important that smooth be identified since it has many meanings to different people. Surface finish can be more than just a cosmetic standard. It can also affect product quality, mold cost, and delivery time. The Society of Plastics Engineers/Society of Plastics Industries standards range from a No. 1 mirror finish to a No. 6 grit blast finish. A mold finish comparison kit consisting of six hardened tool steel pieces and associated molded pieces is available through SPE/SPI. 

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