Numerical investigation of machining of SiC/Al matrix composites by a coupled SPH and FEM

The machining process of SiC/Al matrix composites is characterized by strong nonlinearity, and thus, there are great challenges resulting from excessive deformation and stress concentration at the tool-workpiece interface in solving such problems. Smoothed particle hydrodynamics (SPH) as a particle-based algorithm can efficiently tackle mesh distortion due to large deformation using finite element method (FEM) for cutting simulations. However, the computational efficiency by SPH is far below the counterpart by FEM. As a result, to address such issues with individual use of SPH or FEM, the coupled SPH-FEM algorithm is presented to calculate large deformation of aluminum matrix using SPH and small deformation of SiC particles using FEM. This paper aims to develop a SPH-FEM coupling model of machining SiC/Al matrix composites and compare the results with an equivalent FE model. A good agreement between numerical results from the SPH-FEM model and those from the FE model is achieved, which shows that the SPH-FEM coupling method is an alternative to FEM for predicting the cutting force, chip formation, and machined surface morphology. The developed SPH-FEM model is also employed to investigate the influence of the cutting parameters including SiC volume fraction, cutting velocity, and uncut chip thickness on the cutting force. Finally, the orthogonal cutting experiments were conducted to validate the presented SPH-FEM model. Numerical results are in good agreement with experimental results, which confirms that SPH-FEM can accurately predict the resulting cutting force and machined surface morphology.