Model-based control of surface integrity in hard turning

目的是在用CBn或硬质合金刀具车削淬火和调质42CrMo4钢（48 HRC, Rm = 1557 MPa）时，对与生产相关的表面完整性性能进行直接和间接的过程监测和控制。因此，将研究材料的外围区特性显著影响功能的组件。直接过程监测是指在过程中利用微磁涡流法对表面完整性进行检测。间接过程监控通过可在工业环境中使用的传感器进行，传感器在线记录过程中的温度和切削力分量，并根据模型得出当前表面完整性特性的结论。在此过程中，对晶粒尺寸分布、残余应力和相分数的边界区特性进行了监测。首先，将在第一个供资期间实施可靠的监测系统，然后在第二个供资期间扩大监测系统，包括一项条例。由于可及性有限，不可能在KHz和10 μ m范围内以高空间和时间分辨率监测工业车削过程中的热和机械状态变量。然而，它可以以集成热电偶、声发射传感器、测功机和高温计的形式实现，用于选择性或整体监测状态变量。然而，目前尚不清楚这些具有低时间和空间分辨率的状态变量的选择性或整体测量如何与整个切割区域的高分辨率状态变量相关联。这种相关性在一个类比过程中进行了研究，该过程近似于车削过程的条件，同时允许用于车削过程的面向应用的传感器技术以及高空间和时间分辨率传感器（高速摄像机）的可访问性。为了预测可在加工区域测量的过程状态变量与导致金属边缘区域修改的空间和时间分辨状态变量之间的相关性，然后开发了物理或经验模型。为了获得高空间和时间分辨率，采用DIC法测量应变场和应变速率场，采用热成像法测定温度场。所开发的模型可以与面向应用的车削过程传感器结合使用，以间接控制表面特性，只要过程状态变量与边缘区域修改之间的关系是已知的。这也需要在类比过程中或通过经过验证的数值模拟来分析这种相关性。与此平行，微磁涡流测量方法用于类比过程，允许直接控制。

The aim is the combined direct and indirect process monitoring and control of defined production-related surface integrity properties during the turning of quenched and tempered 42CrMo4 steels (48 HRC, Rm = 1557 MPa) with CBn or carbide tools. Thus a material will be investigated for components whose peripheral zone properties significantly influence functionality. Direct process monitoring refers to the detection of the surface integrity properties via micromagnetic eddy current methods in the process. Indirect process monitoring is carried out via sensors that can be used in industrial environments, which record temperatures and cutting force components online in the process and allow conclusions to be drawn on current surface integrity properties based on models. During the process, the boundary zone properties of the grain size distribution, residual stresses and phase fractions are to be monitored. First of all, a reliable monitoring system will be implemented in the first funding period, which will then be extended to include a regulation in the second funding period. Due to limited accessibility, it is not possible to monitor the thermal and mechanical state variables in the industrial turning process with high spatial and time resolution in the KHz and 10 µm range. However, it can be achieved in the form of integrated thermocouples, acoustic emission sensors, dynamometers and pyrometers for selective or integral monitoring of state variables. However, it is not known how these selective or integral measurements of the state variables with low temporal and spatial resolution correlate with high-resolution state variables in the entire cutting zone. This correlation is investigated in an analogy process, which approximates the conditions of the turning process and at the same time permits accessibility for the application-oriented sensor technology for the turning process as well as high spatial and time resolution sensors (high-speed cameras). In order to predict the correlation between process state variables that can be measured in the machining zone and spatially and time-resolved state variables that cause a modification of the metal edge zone, physical or empirical models are then developed. For the high spatial and time resolution, both the DIC method for measuring strain and strain rate fields and thermography are used for determining temperature fields. The developed models can be used in conjunction with application-oriented sensors for the turning process to indirectly control the surface properties, as far as the relationship between process state variables and edge zone modification is known. This also requires the analysis of this correlation in the analogy process or by means of validated numerical simulations. Parallel to this, micromagnetic eddy current measurement methods are used in the analogy process, which permit direct control.