1.2738 Tool Steel in Insert Molding: Material Selection for Overmolding Applications
Insert molding and overmolding have become indispensable processes in modern manufacturing — enabling the production of multi-material components that combine the structural rigidity of metal inserts with the design freedom and functional versatility of engineering plastics. Applications span automotive connectors, medical device handles, consumer electronics housings, and industrial control components. Behind the precision of every insert mold lies a critical material selection decision: what tool steel delivers the combination of polishability, toughness, corrosion resistance, and dimensional stability that insert and overmolding tooling demands? For medium-to-high production insert molds, 1.2738 tool steel has become one of the most specified mold steels globally — and for good reason. This article examines the material characteristics of 1.2738, the specific demands of insert molding and overmolding tooling, and why 1.2738 is frequently the optimal choice for this applicat...