Deep hole drilling using senor integrated tools to adjust defined functional characteristics into the near-surface peripheral zone

暴露在高度交变压力载荷下的部件（例如大型柴油发动机中的喷射部件）的深孔对近表面外围区域的性能要求很高。在加工过程中必须避免在镗孔壁上形成微裂纹，因为这可能导致部件失效。这是由表面缺陷或不利的残余应力条件引起的。使用单唇深钻方法可以获得高表面质量，但残余压应力必须由后续加工过程（例如自强化）引起。这与额外的加工工作以及对先前深钻工艺瞬态条件的响应灵活性低有关。该项目的主要目标是对过程变化进行计量检测，并通过过程内控制方法对过程变化进行补偿。在项目的第一阶段，开发并验证了用于过程中热-机械状态检测的传感器集成单唇钻井工具，加工温度的数值-解析组合补偿模型，加工和材料模型。过程控制器也被概念化了。对热处理后的42CrMo4钢（ASTM A331）进行了加工试验。后续项目以第一阶段资助的成果为基础，旨在开发一种基于软传感器的鲁棒控制器，该控制器可以专门调节深孔的近地表区域特性。以下子目标是在这里追求：在近表面微观结构（晶体塑性）的机制的详细了解，在位错动力学和分离过程在材料的原子水平。合并在第一个资助阶段创建的关于近表面区域特性和加工参数之间相关性的模型。在材料和需求相关（非时间关键）和过程相关边界条件（时间关键）在控制器架构内结合并汇集在一起的控制器环境中，用于目标影响近地表区域的控制策略。基于软、硬件的深孔钻孔过程控制的概念，控制器的输入变量是工具在有效点的加速度和温度（通过传感器集成工具和补偿模型，从第一个项目阶段开始）以及机械负载（力，通过测力计的力矩）。控制变量为单齿钻的转速和进给速率。基于输入和输出变量以及输出变量的时间相关性，提出了一种合适的控制器概念，将控制器的任务划分为时间临界域和非临界域。控制器与机器控制系统相连。根据应用场景对控制器和控制策略进行了验证。

Deep holes in components being exposed to highly alternating pressure loads (e.g. injection components in large diesel engines) are subject to high demands on the near-surface peripheral zone properties. Microcrack formation in the bore wall must be avoided during machining, as these can lead to component failure. This is caused by surface defects or unfavorable residual stress conditions. High surface quality can be achieved by using the single-lip deep drilling method, but residual compressive stresses must be induced by subsequent machining processes (e.g. autofrettage). This is associated with additional machining effort as well as low flexibility in responding to transient conditions of previous deep drilling processes.The projects main object is the metrological detection of process changes and their compensation by means of in-process-capable control approaches. In the first project phase a sensor-integrated single-lip drilling tool for in-process detection of the thermo-mechanical state, a combined numerical-analytical compensation model of the machining temperature, machining and material models were developed and validated. Also a process controller was conceptualized. Machining tests were performed on the heat-treated steel 42CrMo4 (ASTM A331).The follow-on project is based on the results of the first funding phase and aims to develop a robust controller based on a soft sensor, with which the near-surface zone properties of deep holes can be specifically adjusted. The following sub-goals are pursued here: A detailed understanding of the mechanisms in the near-surface microstructure (crystal plasticity), on dislocation dynamics and on separation processes at the atomistic level in the material. Merge of models created in the first funding phase on the correlation between near-surface zone properties and machining parameters. Control strategies for the targeted influencing of the near-surface zone in a controller environment in which material- and requirement-dependent (not time-critical) and process-dependent boundary conditions (time-critical) are combined and brought together within a controller architecture. Concepts of a soft- and hardware-based in-process control for deep hole drilling, where input variables of the controller are the tool acceleration and temperature at the effective point (by means of sensor-integrated tool and compensation model taken from the first project phase) as well as the mechanical load (forces, moment via dynamometer). The control variables are the rotational speed and the feed rate of the single-lip drill. Based on the input and output variables as well as the time relevance of the output variables, a suitable controller concept is available, which divides the tasks of the controller into time-critical and -uncritical fields. The controller is connected to the machine control system. Controller and control strategies are validated on the basis of application scenarios.