Process-reliable adjustment of subsurface zone properties in the machining of high-strength and ductile steels using an adaptive manufacturing system

影响部件表面下区域是制造过程中的一个基本步骤。亚表层的马氏体硬化和近净形状制造相结合，代表了以节能和省时的方式生产具有耐磨亚表层的部件的巨大潜力。在第一个资助期，开发了在线软测量，加深了对车削过程中奥氏体微结构成分向马氏体转变的理解。该项目的目的是研究一种动态前馈回路，用于通过变形诱导的奥氏体-马氏体相变来调整高强度和延性钢的加工过程中亚表层性能的过程安全。综合考虑了多级车削加工过程中待调整的几何形状、表面质量和亚表面条件的组合。在检测到的初始状态的基础上，使用车削过程中的相变的相互关系的知识来设置适当的过程参数，以便能够在过程中产生所需的特性。为此，评价了深冷条件下外纵向车削过程中对残余奥氏体相变的干扰影响。所需目标状态的设置基于工艺NC仿真中的局部变换过程的建模，并考虑了与过程相关的不确定性。在建立动态亚表层模型的基础上，根据亚表层的微观结构对过程涡流特性进行了预测。所有元素都被纳入到动态前馈控制中，以有针对性地调整工艺中的奥氏体-马氏体转变。对该方法的可能性和局限性的研究为利用动态前馈控制设置各种指定目标值的稳健性提供了基础知识。

Influencing the component subsurface zone is an elementary step in the manufacturing process. A combination of martensitic hardening of a subsurface zone and near-net-shape manufacturing represents a great potential to produce components with wear-resistant subsurface zones in an energy- and time-saving way. In the first funding period, an in-process soft sensor was developed and a deeper understanding of the transformation of austenitic microstructural constituents into martensite in a turning process was obtained. The aim of the proposed project is to investigate a dynamic feedforward loop for the process-safe adjustment of subsurface zone properties in the machining of high-strength and ductile steels by means of a deformation-induced austenite-martensite transformation. The combination of the geometry to be adjusted, the surface quality and the subsurface condition in the final machining by means of a multi-stage turning process is considered. On the basis of the detected initial state, the appropriate process parameters are set using the knowledge of the interrelationships of the phase transformation in the turning process in order to be able to generate the desired properties in the process. For this purpose, disturbing influences on the transformation of retained austenite during external longitudinal turning under cryogenic cooling in the process are evaluated. The setting of desired target states is based on the modelling of local transformation processes in a technological NC simulation, taking process-related uncertainties into account. With the help of a dynamic subsurface zone model, the prediction of the in-process eddy current characteristics is to be made on the basis of the subsurface zone microstructure. All elements are incorporated into the dynamic feedforward control for the targeted adjustment of the austenite-martensite transformation in the process. Research into the possibilities and limits of the method provides fundamental knowledge on the robustness of setting various specified target values by means of dynamic feedforward control.