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

塑料提供多种设计选项。因此，这类材料在工业用途中有许多应用。随着高性能塑料的发展，其他轻质材料如铝或镁越来越多地被取代。为了生产大量由塑料制成的零部件，通常使用注塑和挤出工艺。相比之下，数量有限或具有高度复杂几何形状的精密部件则通过机加工工艺制造。塑料机加工的挑战在于由此产生的工艺温度以及某些塑料的吸水倾向。对于某些加工过程，这会导致问题。这尤其适用于制造过程钻孔，其中必须从孔中去除感应热和切屑，以确保安全的过程。对于需要大长径比（l/D比）孔的部件，这会导致加工时间延长，因为需要多次加工中断来去除切屑，并且使用低切削参数来保持尽可能低的诱导热。对于需要大长径比孔的金属部件，使用不同的深孔钻削工艺。虽然深孔钻在金属加工方面得到了广泛的研究，但在塑料加工方面并非如此。因此，本研究的一个目标是研究金属深孔钻削的已知优点是否可以应用于塑料深孔钻削。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过程的孔质量及其与切削数据的相关性进行了研究。基于模拟，计划开发一种刀具形状，该刀具形状允许短加工时间，同时确保高孔质量。为此，将创建基于计算机实验设计与分析（DACE）方法的不同模型，然后将其组合在单个模拟中。为了包含宽范围的不同热塑性树脂，研究了部分结晶和无定形热塑性树脂。

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.