Multi-objective optimization of oblique turning operations
CHALLENGE - Oblique-turning operations differ in several ways with respect to orthogonal turning operations and offer considerable advantages in terms of cutting forces, noise level, and surface quality. Despite most applications requiring oblique turning operations, research is limited to orthogonal turning operations. The objective of this study is to find out the best possible cutting parameters for oblique turning of AISI H13 tool steel, using PCBN inserts, with focus on minimizing main cutting force and tool–chip interface temperature. These both contribute to performance in terms of tool wear and surface integrity of the workpiece.
SOLUTION - Multi-objective optimization of oblique turning operations has been carried out using the finite element (FE) model and multi-objective genetic algorithm (MOGA-II) from modeFRONTIER. The turning operation is optimized in terms of cutting force and temperature with constraints on required material removal rate and cutting power. The 3D FE model developed in ABAQUS simulates cutting forces, temperature and stress distributions, and chip morphology. The tool is modeled as a rigid body, whereas the workpiece is considered as elastic–thermoplastic. The FE model is run with different parameters with central composite design used to develop a response surface model (RSM). The developed RSM is used as a solver for the MOGA-II. The optimal processing parameters are validated using FE model and experiments.
BENEFITS - A good correlation has been found between experiments and simulations. The model developed is able to simulate the phenomenon with a reasonable degree of accuracy with an average error of around 10%. Some further conclusions from this study are: low cutting forces and temperatures are obtained with high rake and inclination angle and at low cutting speed and feed rates, chip flow angle found to be increased by increasing the inclination angle, high temperature region is confined to the tool–chip contact area and found to be decreased as chip moves away from the tool rake face.