Multi Objective Optimization of Dimension Accuracy and Surface Roughness in High-Speed Finishing Milling for the Hard Steel Alloy After Heat-Treatment

Abstract

This paper presents a multi-objective optimization (MO) problem including dimensional accuracy (DA) or dimensional error (DE) and surface roughness (SR) in high-speed finishing milling (HSFM) the SKD11 alloy steel after heat-treatment with hardness above 55HRC. Regression equations describing the relationship between cutting parameters (CP) and DE and SR are built on the basis of the specific experiments results. The Central Composite Design model (CCD) in the Response Surface Methodology (RSM) method is used to construct the experimental matrices. The ANOVA method in DESIGN EXPERT software was used to analyze experimental data. The results of the MO problem are found along with the suitable CP values based on the NSGA-II algorithm. The distinct property of the objective function DE is also considered based on the division of the MO problem solving cases. The research results have important value in finding suitable sets of cutting parameters and meeting multiple objectives simultaneously when machining HSM for hard materials.