Tool making in injection moulding is significantly influenced by the requirements of the plastics processing industry. Profitable production of increasingly individualized end products requires increasingly higher process speeds, low reject rates and long tool durability. Furthermore, the requirements are rising not only in terms of quality, but also in terms of the geometries to be produced, surface design and material and resource efficiency.
While conventional approaches using traditional manufacturing methods such as milling, drilling, wire or sinker EDM reach their physical and economic limits, 3D printing and its high degree of creative freedom offers a huge potential to improve the performance of tools enormously and at the same time save costs in production. This includes in particular an improvement in the temperature control of the tool through innovative cooling concepts as well as a reduction of manufacturing efforts and costs through integral design.
At the appropriate time, metallic 3D printing, in particular the powder bed-based manufacturing process Selective Laser Melting (SLM), is already finding its first applications in the production of performance-optimized tool inserts. The placement of near-surface tempering canals can greatly decrease the cycle times of the injection moulding machine compared to conventionally manufactured tools.
In analogy to the classic tool, simple circular cross-sections are currently used in the printed tool inserts for the design of the cooling canals. However, 3D printing, with its great design freedom, offers much more possibilities in the design of the fluid-flowed temperature control canals. For example, modern methods of computer-aided and simulation-driven design can be used to implement innovative and highly efficient cooling concepts, such as topologically optimized canal structures or optimized structural cooling using special cellular structures with large heat-conducting surfaces and low flow resistances.
In contrast to conventional manufacturing processes, an increase in the geometric complexity of a component in metallic 3D printing does not necessarily lead to higher manufacturing costs. Against this background, the idea for the planned innovation project was born to develop a new generation of high-performance tools with optimized cooling structure and venting for injection molding by making extensive use of the design freedom of additive manufacturing - with a focus on powder-bed-based metal processing methods. With this technology it will be possible,
- to process materials that are very difficult to handle, such as short fibre or particle reinforced high-performance plastics, better than before
- to manufacture extremely thin-walled or complexly shaped structures and components without defects, or
- to produce high-precision components with very tight geometric tolerance requirements.
The technology to be developed for the design and manufacture of innovative high-performance tools for injection moulding applications includes the 4 sub-projects:
Subproject 1 - KMS
Optimised venting technology for 3D-printed mould inserts
Subproject 2 - CellCore
Functionally-optimized cooling structure for 3D printed tool inserts
Subproject 3 - edmos
3D-Finishing technology for powder removal and surface cleaning of complex-shaped cooling canals.
Subproject 4 - TUBAF
Prozessseitige Optimierung des SLM für komplexe Innenstrukturen und gezielte Materialeigenschaften