Basic research concerning Electrical Discharge Machining with additive manufactured tool electrodes

在电火花模具下沉的过程链中，工具电极的制造工作量最高。由于冲洗不足，这一努力会随着工具电极磨损ϑ的增加而成倍增加。为了补偿工具电极的磨损，需要更多的工具电极。选择性激光熔化(SLM)的制造方法为电火花加工工具电极提供了新的机会。具有内部冲洗通道的复杂形状电极几何形状可以通过添加制造的制造原理来实现。碳化钨的材料性能是电火花加工的理想材料。由于加工碳化钨的工作量较大，碳化钨成形电极的制造一直被忽视。利用SLM加工碳化钨的可能性，该材料除了可用于电火花钻削加工外，还可用于电火花加工的成形电极。本研究项目的目的是验证添加剂制造的碳化钨作为电火花加工工具电极材料的有效性。SLM工艺参数的变化导致添加剂加工工具电极的钴含量GCO不同，并改变了电火花加工的工艺行为。应确定适合于用碳化钨工具电极粗加工不同材料的工艺参数。内冲洗通道的实施进一步改善了加工结果，特别是在加工大深宽比A时。对实验结果进行了科学分析，得出了在电火花加工领域的广泛发现。所获得的知识和硬质合金WC-Co的特定材料特性有助于提高电火花加工中的材料去除速度、VW和电极损耗等重要工艺特性。本研究项目的研究成果可用于进一步的科学研究，如通过不同涂层的进一步加工来改善SLM电极。该添加剂制造的电极可用于精加工和抛光工艺。另一项研究可以分析在WC-Co中添加合金化添加剂，如碳化钒，以改善电火花加工工艺。

In process chains with EDM die-sinking the highest manufacturing efforts can be found in the production of tool electrodes. This effort multiplies with increasing tool electrode wear ϑ because of insufficient flushing. A higher amount of tool electrodes is required in order to compensate the tool electrode wear. The manufacturing method Selective Laser Melting (SLM) offers new opportunities in machining tool electrodes for EDM applications. Complex form electrode geometries with interior flushing channels can be realised with the manufacturing principles of additive manufacturing. The material properties of tungsten carbide are ideal for the application in EDM. Due to the high effort in machining tungsten carbide, the manufacturing of form electrodes out of tungsten carbide has been neglected so far. By the possibility to machine tungsten carbide by SLM, this material can be applied for form electrodes in EDM die-sinking besides the application in EDM drilling operations.The aim of this research project is the validation of additive manufactured tungsten carbide as tool electrode material for EDM. The variation of the SLM process parameters leads to differing cobalt content GCo and changing EDM process behaviour of the additive manufactured tool electrodes.Appropriate process parameters for rough machining of different materials with tungsten carbide tool electrodes shall be identified. The implementation of interior flushing channels causes further improvement of the processing results, especially when machining high aspect ratios A. The scientific analysis of the experimental results leads to extensive findings in the area of EDM. The acquired knowledge and the specific material characteristics of the carbide WC-Co allow the improvement of important process characteristics like material removal rate VW and electrode wear in EDM die-sinking. The results of this research project can be used for further scientific investigations like improving the SLM electrodes by further processing with different coatings. The additive manufactured electrodes could be applied for finishing and polishing processes. Another investigation can analyse the addition of alloying additives to WC-Co, such as vanadium carbide in order to improve the EDM process.