Project Details
Projekt
Model-based identification of surface properties during the milling process of Ti-6Al-4V
Subject Area
Metal-Cutting and Abrasive Manufacturing Engineering
Term
from 2018 to 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 402128304
The primary objective of the research project is to control the milling process using a model-based approach in order to generate defined geometries and residual stresses in titanium components (Ti-6Al-4V) simultaneously. In the first phase of the project a real-time, analytical model, which describes the relationship between the process parameters and the residual stresses, is developed. The tool wear as well as scattering material properties of the unmachined parts are also considered as an observable disturbance variable and as a hidden disturbance variable, respectively. The control strategy relies on in-process measurements of temperatures and cutting forces for which a prototypical sensory toolholder is used. To analytically describe the complex relationship between the process parameters and the surface layer state, a two-step approach is selected. The first step is to model the heat input and cutting forces within the process zone. In a second step, the resulting residual stresses and the hardness profile within the machined part are modeled. The resulting sub models are then put together in an overall model.The work of the first project phase provides real-time models that can be used to determine the thermomechanical component loads during the milling process of Ti-6Al-4V. These form the basis for the modeling of the residual stress state and of the hardness profile of the component edge layer after machining. In the second phase of the project, the models are used for the dynamic process control of the residual stress state. This includes the development and implementation of a suitable control concept and the verification of its robustness against interferences. Furthermore, the models and the control system can be extended by additional control variables. In addition to the conventional process parameters already taken into account, this includes, for example, the influence of the tool angle of attack.
DFG Programme
Priority Programmes
Subproject of
SPP 2086:
Surface Conditioning in Machining Processes
