Development of a simulation based method for a load dependent optimisation of cemented carbide tools for nickel-base alloys - Variable micro geometry along the cutting edge

该知识转移项目建议基于基础研究项目：为优化硬质合金麻花钻的热机械载荷和磨损行为建模。以往的研究主要集中在切屑形成的三维有限元模拟，以预测钻削过程中刀具刃口准备对刀具载荷的影响。空间分辨率低，计算时间长，给仿真分析带来困难。因此，提出了一种替代模型。对钻具第一主切削刃上不同的正交切削进行了仿真。该方法具有较高的空间分辨率和较短的计算时间，值得在镍基合金的钻削加工中推广应用。这包括使用实验设计来考虑局部工艺条件，如钻削中的半径相关的切割速度。刀具磨损采用Usui模型进行模拟。刀具磨损的参数描述可用于刀具磨损的统计建模，从而为参数值的每一种可能组合提供磨损预测。此外，还利用统计模型找出了使刀具磨损最小的刀具刃口参数。这种方法在这里被扩展到在单个刀具旋转过程中具有未切削切屑厚度的特征变化的铣削过程。此外，还开发了一种测量预制刀具刃口的方法。最后，在实验测试中将优化工具与标准工具进行了比较。

This knowledge transfer project proposal is based on the fundamental research project: Modelling of the thermo-mechanical loads and wear behavior for optimisation of cemented carbid twist drills. The former project focused on the three-dimensional FE-simulation of chip formation for the prediction of the influence of the cutting edge preparation on the tool load during drilling processes. The low spatial resolution and long calculation times lead to difficulties during the analysis of the simulation. Therefore, an alternative model was proposed. These simulations of orthogonal cutting are carried out, which represent different orthogonal cut on the first primary cutting edge of a drilling tool. This technique offered the advantage of higher spatial resolution and shorter calculation times and should be applied and extended for drilling and milling of nickel-base alloys. This includes the consideration of local process conditions like the radius-dependent cutting speed in drilling by using design of experiments. The tool wear is simulated by the model of Usui. The parametric description of the cutting edge can be used for the statistical modelling of the tool wear which provides a wear prediction for every possible combination of parameter values. Furthermore, the statistical model is used to find cutting edge parameters which minimize the tool wear. This approach is extended here to milling processes, which have characteristic variations of the uncut chip thickness during a single tool rotation. Furthermore, a method is developed for measuring prepared cutting edges. Finally, optimized tools are compared to standard tools in experimental tests.