Fundamental investigations on the hole accuracy and surface quality when single-lip deep-hole drilling of thermoplastic resin by adjusting the tool shape

塑料提供了多种设计选项。因此，这类材料在工业上得到了许多应用。随着高性能塑料的发展，铝或镁等其他轻质材料被越来越多地取代。为了生产大量的塑料零部件，经常使用注塑和挤出工艺。相比之下，有限数量或具有高度复杂几何形状的精密部件是通过机械加工工艺制造的。塑料加工的挑战是由此产生的工艺温度和某些塑料吸水的倾向。对于某些加工过程，这会导致问题。这尤其适用于制造工艺钻探，在钻探过程中，为了确保工艺安全，必须将感应热和切屑从孔中移除。对于需要高长径比(L/D-Ratio)孔的零件，这会导致加工时间较长，因为去除切屑需要多次工艺中断，并且需要使用低切削量来保持尽可能低的感应热。对于需要大长径比(L/D-Ratio)孔的金属零件，采用不同的深孔钻孔工艺。虽然深孔钻孔在金属加工方面得到了深入的研究，但在塑料加工方面却并非如此。因此，本研究的目的之一是研究金属深孔钻削的已知优势是否可以应用于塑料的深孔钻削。采用统计试验设计的方法，对不同热塑性树脂的单唇深孔钻削工艺进行了研究，考察了孔的质量及其与加工数据的相关性。在模拟的基础上，计划开发一种在保证高孔质量的同时允许较短加工时间的刀具形状。为此，将创建基于计算机实验设计和分析方法(DACE)的不同模型，然后将这些模型组合在单个模拟中。为了组成不同的热塑性树脂的广谱，研究了部分晶态和非晶态热塑性树脂。

Plastics offer a variety of design options. Hence many applications result for this class of materials in industrial use. By the development of high-performance plastics other lightweight materials such as aluminum or magnesium are increasingly substituted. For the production of a large number of parts and components made of plastics, injection molding and extrusion processes are often used. In contrast, precision components available in limited quantities, or with a highly complex geometry, are made by machining processes.Challenges for the machining of plastics are the resulting process temperatures and the tendency of some plastics to absorb water. For some machining processes this results in a problem. This applies especially to the manufacturing process drilling, in which the induced heat and the chips have to be removed from the hole in order to ensure a safe process. For components requiring a hole with a high length to diameter ratio (l/D-ratio), it results in high process times, because many process interrupts are necessary to remove the chips and low cutting data are used to maintain the induced heat as low as possible.For metal components with holes that require a large l/D-ratio different deep-hole drilling processes are used. While deep-hole drilling is intensively investigated concerning the machining of metals, this is not the case in terms of machining of plastics. Therefore one goal of this research is to investigate if the known advantages of the deep-hole drilling of metals can be applied to the deep-hole drilling of plastics. Using the methods of statistical experimental design the single-lip deep-hole drilling process will be investigated for different thermoplastic resins with respect to the hole quality and its correlation with the cutting data. Based on a simulation it is planned to develop a tool shape which allows small processing times while ensuring a high hole quality. For this purpose, different models based on the method of Design and Analysis of Computer Experiments (DACE) will be created which are then combined in a single simulation. To comprise a broad spectrum of different thermoplastic resins partially crystalline and amorphous thermoplastic resins are investigated.