Dislocation Density Based Material Model Applied in PFEM-simulation of Metal Cutting

Metal cutting is one of the most common metal-shaping processes. In this process, specified geometrical and surface properties are obtained through the break-up and removal of material by a cutting edge into a chip. The chip formation is associated with large strains, high strain rates and locally high temperatures due to adiabatic heating. These phenomena together with numerical complications make modeling of metal cutting challenging. Material models, which are crucial in metal-cutting simulations, are usually calibrated against data from material testing. Nevertheless, the magnitudes of strains and strain rates involved in metal cutting are several orders of magnitude higher than those generated from conventional material testing. Therefore, a highly desirable feature is a material model that can be extrapolated outside the calibration range. In this study, a physically based plasticity model based on dislocation density and vacancy concentration is used to simulate orthogonal metal cutting of AISI 316L. The material model is implemented into an in-house particle finite-element method software. Numerical simulations are in agreement with experimental results for different cutting speed and feed.