Investigation of the operational behaviour of binderless cemented carbide for high-precision milling of an aluminium alloy containing silicon and magnesium

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Tool and mould making is one of the most important industrial sectors of the manufacturing industry in Germany. Due to the growing technical development, the tool and mould making is subject to continuously increasing demands on shape accuracies as and surface roughness values of the manufactured components. The aluminium-magnesium-silicon alloy (AlMgSi1) is the most commonly used material for the pre- and pilot-series up to the first phase of series production of manufactured injection moulds. For this purpose, milling is a suitable manufacturing process for the production of injection moulds consisting of the AlMgSi1-alloy. The state of the art shows that uncoated cemented carbide tools are still used for the roughing process. These tools consist of a binder phase made of cobalt, which leads to considerable tool wear due to a temperature-induced removal of the binder phase. The structural cohesion of the cutting material is reduced, resulting in lower shape accuracy as and higher surface roughness values as well as a high economic load. In addition, the finishing process will realised with cost-intensive cutting tools made of diamonds, which results in high process costs cp. For this reason, the operational capability of the binderless cemented carbide as an innovative cutting material will be analysed. Due to the hardness H as well as the micro-structure properties, the process capability and the applicability will be affected. For this purpose, detailed scientific studies will be carried out. The objective of the research work is the identification of significant wear characteristics of the binderless cemented carbide tools, the development of a suitable process technology for the preparation of the cutting edges as well as the analyse of the operational capability for the cutting of the AlMgSi1-alloy. To realise the research project with regard to the scientific research hypothesis, the specific material properties will be characterised and analysed. Based on this, detailed investigations for the tool wear will be carried out to determine the significant wear characteristics of the binderless cemented carbide tools. Due to a high stability and the implementation of complex geometric structures, two-edge ball end mills will be applied. For the preparation of the grinded manufactured cutting edges to reduce the maximum chipping of the cutting edge RS,max, an immersed tumbling process will be carried out, which leads to improved conditions for the subsequent machining tests. Based on this, the operational capability of the binderless cemented carbide tools and the wear behaviour depending on the path length lc will be analysed to evaluate the scientific research hypothesis as well as to enable high tool life times TSt and an economical machining of the AlMgSi1-alloy.