Optimizing of PVD coatings for dry cutting applications by FE-simulation

采用物理气相沉积（PVD）硬质涂层对刀具进行涂层，可显著提高刀具的使用寿命和生产率。在许多情况下，由于薄膜的热障效应以及摩擦系数的降低，可以省略润滑剂的使用。根据切削操作的类型，量身定制的PVD涂层可以通过特定的涂层性能设计（如硬度、抗氧化性、摩擦系数和扩散系数）来提高刀具的使用寿命。对这些涂层的要求根据要执行的任务而变化，并受到要加工的材料、加工参数和加工工具的总体几何形状的影响。今天，针对特定切割任务的涂层系统的常规开发包括各种具有详细实验参数研究的测试系列。特别是，在实际实验中对切削行为的研究导致了大量的资源、时间和成本。提出的研究项目的目标是通过使用有限元模拟来优化用于干式加工的PVD硬涂层刀具的开发过程。因此，将开展基于CrAl(X)N干式加工操作的涂层体系模拟辅助合成的基础概念研究。使用组件-工具接触的磨损模拟将由PVD涂层补充。通过调整PVD合成参数，在有限元模拟的基础上实现了层的性能指标，并进行了实验验证。通过有限元模拟、PVD涂层的合成、性能曲线的基本表征和干切削实验之间的相互作用，涂层体系的开发过程将得到显著优化。

The coating of cutting tools by means of PVD (physical vapor deposition) hard coatings increases the tool life and productivity significantly. In many cases, use of lubricants can be omitted due to the thermal barrier effect of the films as well as reduction of the coefficient of friction. Depending on the type of cutting operation, individually tailored PVD coatings can improve tool life time by specific design of coating properties such as hardness, oxidation resistance, friction coefficient and diffusivity.The requirements for these coatings vary according to the task to be performed and are influenced by the material to be machined, the machining parameters and the total geometry of the machining tool. Today, a conventional development of a coating system for a specific cutting task includes a variety of test series with elaborate experimental parameter studies. In particular, the investigation of the cutting behaviour in practical experiments causes significant ressources, time and costs.The goal of the proposed research project is to optimize the development process of cutting tools with PVD hard coatings for dry machining through the use of FE simulations. Therefore, fundamental conceptual studies concerning the simulation assisted synthesis of coating systems on the basis of CrAl(X)N dry machining operation will be conducted.The wear simulation using component - tool contact will be supplemented by the PVD coating. The specifications of the layer properties on basis of FE simulations are realized by adjustment of the PVD synthesis parameters and experimentally verified. From the interaction between FE simulation, synthesis of PVD coatings, fundamental characterization of property profiles and dry cutting experiments the development process of coating systems will be significantly optimized.