Design freedom offered by the SLM technology can be applied to the manufacture of inserts and molds. The main objective of the injection mold and casting is to ensure proper cooling of the part. This cooling depends on the heat transfer between the molten metal and the mold. To optimize this cooling may be used components manufactured by SLM internal cooling channels that discurran near the surface.

The most common approach is the fabrication of inserts which are placed on blocks prefrabicados mold. Using these inserts provides uniform heat transfer (prevents overheating of mold parts), improving the surface quality of the molded parts and considerably reduces injection cycles.