Development and verification of a constitutive approach for the determination of high-speed flow curves by means of the cutting process

 

Compared to conventional empirical process design based on experimental cutting tests, simulation-based process development and design offers the potential to reduce the development time and costs of cutting processes. Different input models are necessary for the modelling of machining processes. In addition to the friction model to describe the mechanical interaction between the tool and the workpiece, thermal models and material models are required. The determination of material models poses great challenges for production engineering due to the thermo-mechanical load collective acting in the machining process. This is due to the fact that the strains, strain rates and temperatures occurring in the machining process can only be represented insufficiently by conventional material tests.

Therefore, this research project pursuesdan inverse approach in which a methodology for determining parameters of material models is created by means of FEM chip formation simulation. For this purpose, the cutting force components, cutting temperatures and fields as well as the chip shape and formation determined from experimental orthogonal cutting tests were used as validation parameters for the FEM chip formation simulation. By a comparison between experimentally and simulatively determined parameters, the material model as well as the determined parameters can be assumed as valid if there is sufficiently good agreement.