A PARAMETRIC STUDY OF THE MODELING OF ORTHOGONAL MACHINING USING THE SMOOTHED PARTICLE HYDRODYNAMICS METHOD

摘要

Modeling machining processes with conventional finite element methods (FEM) is challenging due to the severe deformations that occur during machining, complex frictional conditions that exist between the cutting tool and the workpiece, and the possibility of self contact due to chip curling. Recently, the Smoothed Particle Hydrodynamics (SPH) method has emerged as a potential alternative for modeling machining processes due to its ability to handle severe deformations while avoiding mass and energy losses encountered by traditional FEM. The method has been implemented in several commercial finite element packages such as ABAQUS and LS-DYNA for solving problems involving localized severe deformations. Numerous control parameters are present in a typical SPH formulation. The purpose of this work is to evaluate the effect of the three most important parameters, namely, the smoothing length, particle density, and the type of SPH formulation. The effects of these parameters on the chip morphology and stress distribution in the context of orthogonal machining of AISI 1045 steel are investigated. The LS-DYNA finite element package along with Johnson-Cook material model is used for this purpose. Results from the parametric study are presented and compared with the previously reported results in the literature. In addition, the sensitivity of chip morphology and stresses to Johnson-Cook parameters for AISI 1045 steel is also investigated by considering five different sets of values reported in the literature for this steel.