Investigations on optimization of the cutting edge of twist drills for the machining of the high temperature resistant nickel-based alloy Inconel 718

应用项目是上一个DFG项目的延续。在这一框架内，开展了广泛的调查，以分析在Inconel 718钻探过程中发生的载荷。特别是对刀具刃口和刀具与工件接触区的热机械载荷进行了研究，以期深入了解钻削过程。根据所获得的结果，研制、制造和使用了在后刀面上具有几何简单缩回的钻具。这一改进显著延长了刀具寿命，特别是在应用了生产率提高的参数集时。因此，本项目的目的是通过在后刀面上产生几何结构来进一步发展后刀面收缩的基本概念，该几何结构用于引导冷却润滑剂流动并有效地将其引导到刀具刃口。通过详细的模拟和实验分析，首先研究了冷却润滑剂流动以及由此产生的刀刃上的机械和热相互作用，以评估已经开发的后刀面收缩的效果。在此基础上，考虑计算流体动力学(CFD)模拟的反馈，对复杂的后翼面结构进行了有针对性的设计。然后，用这种方法开发的工具通过激光或研磨制造，并在实验测试中进行评估。除了基本的刀具寿命试验外，还进行了热载荷分析和对冷却润滑剂流动的影响的研究，以验证模拟确定的复杂后刀面结构的优势。

The applied project is the continuation of the last DFG project. Within this framework, extensive investigations were carried out to analyse the loads occurring during the drilling of Inconel 718. Especially the thermomechanical loads on the tool cutting edge and the contact zone between tool and workpiece were investigated in order to gain insights into the drilling process. Based on the obtained results, drilling tools were developed, manufactured and used which have a geometrically simple retraction on the flank face. This modification led to significant increases in tool life, especially when parameter sets were applied that feature an increased productivity. Therefore, the aim of this project is to further develop the basic concept of a retraction on the flank face by yielding geometric structures onto it which serve to channel the cooling lubricant flow and effectively guide it towards the cutting edge.By means of detailed simulative and experimental analyses, the cooling lubricant flow as well as the resulting mechanical and thermal interactions at the cutting edge are first investigated in order to evaluate the effects of the already developed flank face retraction. On this basis, a targeted design of complex flank face structures is carried out taking into account the feedback from a Computational Fluid Dynamics (CFD) simulation. The tools developed in this way are then manufactured either by laser or grinding and evaluated in experimental tests. In addition to basic tool life tests, analyses of the resulting thermal loads and investigations of the influence on the cooling lubricant flow are carried out in order to verify the simulatively determined advantages of the complex flank face structures.