Additive Manufacturing. Optimization of Injection Molds by Conformal Cooling

Metal additive manufacturing processes offer greater freedom of design and production than traditional processes, enabling the manufacture of highly complex parts, with weight savings that are decisive in certain applications, for example in the aerospace and medical sectors. However, these applications are not the only ones of interest: metal additive manufacturing can also be used to advantage in the production of – tools, or parts – of polymer injection molds: cavities or inserts. The advantage of producing an injection mold cavity using metal additive manufacturing does not lie in the production of molding surfaces: as they are not precise enough, all surfaces in contact with the plastic injection part will have to be machined. The key point that has enabled 3D printing to establish itself in the tooling sector is the creation of complex cooling channels inside the mold. This is known as Conformal Cooling: the channels are designed to be as close as possible to the molding surface, thus optimizing and homogenizing the cooling of the plastic part injected into the mold. Optimized cooling reduces injection cycle times and thus increases mold productivity. Homogenization, on the other hand, ensures better part quality and avoids certain injection defects such as weld lines, shrinkage or part deformation on demolding.