Injection molding is the most spread plastic processing manufacturing process due to high production speed, low cost per component and the possibility for automation. The development of Soft Tooling for mold inserts using polymer-based additive manufacturing has recently raised. Additive manufacturing enables the production of complex tool designs, thus raising the flexibility of Soft Tooling. However, polymer-based Soft Tooling suffers from low tool life due to their low strength and low thermal resistance. Furthermore, long cooling cycles during the injection molding, in consequence of poor thermal conductivity, as well as dimensional deviations are the main disadvantages of this manufacturing method. To enhance the life span of the tool inserts the influence of metallization by thermal arc spraying of the printed polymer Soft Tooling will be presented in this talk.

The influence of different surface pretreatments of additively manufactured polymer mold inserts on the adhesion with the metallic layers was investigated. In order to evaluate the effect of the 3D printing process, multi Jet Fusion (PA 12) and selective laser sintering (PA12) processes were examined. The sprayed coatings consist of single metal layers or a combination from zinc, copper and steel layers. Coating thickness, surface roughness and adhesion between metallic coating and polymer substrate will be presented.