Fundamental analysis of EDM die-sinking applying different tungsten carbide

在电火花成形加工中，电极材料的选择与不同的边界条件有关。经济的生产需要高的材料去除率V ~ W，同时具有最小的相对刀具磨损量。因此，物理去除原理导致需要高电导率κ、热导率λ、比热容cp和高熔点TS，以确保工具电极处的最佳可能放电特性和散热。制造复杂和精细的结构，如具有低壁厚dW的薄棒，需要材料具有足够的机械强度E。硬质合金的材料特性非常适合在电火花加工中应用。由于加工碳化钨的高难度，迄今为止，由碳化钨制成的成形电极的制造一直被忽视。本研究项目的目的是验证不同规格的碳化钨作为电火花加工的工具电极材料，以及确定适当的工艺参数，宏观和微观加工的钢材料。对实验结果的科学分析通过分析不同的碳化钨及其在电火花加工中的相应过程行为，在电火花加工领域获得了广泛的发现。所获得的知识和WC-Co硬质合金的特定材料特性使得能够改善重要的工艺特性，如材料去除率V ~ W和电火花成形加工中的电极磨损。

The selection of an appropriate tool electrode material for die-sinking electrical discharge machining (EDM) is connected to different boundary conditions. An economic production requires high material removal rate V̇W with minimal relative tool wear ϑ at the same time. Thus, the physical removal principle results in a need for a high electrical conductivity κ, thermal conductivity λ, specific heat capacity cp and a high melting point TS to ensure the best possible discharge characteristics and heat dissipation at the tool electrode. Manufacturing of complex and fine structures like thin bars with low wall thicknesses dW requires a sufficient mechanical strength E of the material. 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 made of tungsten carbide has been neglected so far. The aim of this research project is the validation of different tungsten carbide specifications as tool electrode material for EDM as well as identifying appropriate process parameters for macro- and micro- machining of steel materials. The scientific analysis of the experimental results leads to extensive findings in the area of EDM by analysing the different tungsten carbides and their corresponding process behaviour in EDM. The acquired knowledge and the specific material characteristics of the WC-Co carbide enable the improvement of important process characteristics like material removal rate V̇W and electrode wear ϑ in die-sinking EDM.