Model-based identification of surface properties during the milling process of Ti-6Al-4V

Ti-6Al-4V 铣削过程中基于模型的表面特性识别

• 批准号: 402128304
• 负责人: Dr.-Ing. Christian Krempaszky
• 金额: --
• 依托单位: Lehrstuhl für Betriebswissenschaften und Montagetechnik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/402128304?language=en
• 关键词: Model; based; identification; surface; properties

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.

该研究项目的主要目标是使用基于模型的方法控制铣削过程，以便同时在钛部件（Ti-6Al-4V）中生成定义的几何形状和残余应力。在项目的第一阶段，开发了一个实时分析模型，该模型描述了工艺参数和残余应力之间的关系。未加工零件的刀具磨损和散射材料特性也被认为是一个可观察的干扰变量和作为一个隐藏的干扰变量，分别。控制策略依赖于过程中的温度和切削力的测量，其中使用了一个原型的传感器刀柄。为了解析地描述工艺参数和表面层状态之间的复杂关系，选择了两步方法。第一步是对加工区内的热输入和切削力进行建模。在第二步中，对所产生的残余应力和机加工零件内的硬度分布进行建模。第一个项目阶段的工作提供了实时模型，可用于确定Ti-6Al-4V铣削过程中热机械部件的载荷。这些构成了对残余应力状态和加工后部件边缘层的硬度分布进行建模的基础。在项目的第二阶段，模型用于残余应力状态的动态过程控制。这包括开发和实施适当的控制概念，并验证其抗干扰的鲁棒性。此外，模型和控制系统可以通过附加的控制变量来扩展。除了已经考虑到的常规工艺参数之外，这还包括例如刀具攻角的影响。