Minimization of Milling-Induced Residual Stresses in AISI 1045 Steel: Process Optimization using Design of Experiments Taguchi Method

Abstract

Residual stress is responsible for various engineering failures in cases where the magnitude of residual stress exceeds the ultimate strength. With the aim of minimizing the residual stress induced in the machining of AISI 1045 steel, different machining parameters (speed, feed, depth of cut) and the output variables were experimentally investigated in this research. Series of specimens were produced using different machining parameters, and the residual stress in each was measured. When a material is subjected to external forces or thermal treatments, residual stresses can be introduced due to changes in the lattice spacing of the material. These changes in lattice spacing are detected using a non-destructive method based on the x-ray diffraction (XRD) technique. The equipment used is iXRD with MGR40P- Stress measurement system, PROTO CANADA make. The PROTO XRDWIN 2.0 software was an integral part of the XRD machine, which records all the necessary data, calculations and provides the user with surface residual stresses values. Data analysis and the process parameters were optimized using Taguchi L9 orthogonal design of experiments. To determine the effects of the machining parameters on residual stress, Analysis of Variance (ANOVA) was used. The results indicate that the feed rate is only statistically significant parameter on the residual stress with the largest main effect. The optimal setup of machining parameters that cause the lowest residual stress of − 145.4 MPa was identified, with a speed of 710 m/min, a feed of 80 mm/min, and a DOC of 0.2 mm.