Effect of workpiece work hardening on machined surface topography generated in two-step milling process. (May 2022)

• Record Type: Journal Article
• Authors: Song, Wengang; Liu, Zhanqiang; Yao, Gonghou; Khan, Aqib Mashood; Cai, Yukui
• Is Part Of: Journal of manufacturing processes. Volume 77(2022)
• Page Start: 348
• Page End: 360
• Publication Date: 2022-05
• Subjects: Inconel 718 -- Two-step milling -- Surface topography -- Cutting force -- Work-hardening; Production management -- Data processing -- Periodicals; Manufacturing processes -- Periodicals; Procestechnologie; Productietechniek; Production -- Gestion -- Informatique -- Périodiques; Fabrication -- Périodiques; Manufacturing processes; Production management -- Data processing; Periodicals; 670.5
• DOI: 10.1016/j.jmapro.2022.03.039
• Languages: English
• ISSNs: 1526-6125

Abstract

Abstract: The surface topography of the workpiece affects the performance of finished components. The finished component is usually machined with series of machining steps. However, the models had been developed to predict surface topography usually focused on in a single-step machining process. The effect of the previous machining step on the machined surface topography of the current cutting process was ignored. A novel prediction model for surface topography in two-step milling Inconel 718 considering the influence of the work-hardened layer generated in the previous machining process was proposed in this paper. Firstly, the cutting force model with variable force coefficients was developed. The workpiece in the depth direction was layered according to the degree of work hardening, and each layer of workpiece material corresponds to a set of force coefficients. The calculation results with the developed cutting force model were verified using two-step milling experiments. Then, the influence of the work-hardened layer generated in the previous milling process was converted into the cutting force effect on the actual cutting thickness. The actual cutting thickness was superimposed into the cutting edge motion trajectory. The prediction model of machined surface topography generated in the two-step milling process was established considering both effects of cutting edge motion trajectory in the current milling step and workpiece material work hardening due to the previous step of milling. The proposed model can accurately predict the surface topography, and the average relative error of the surface roughness ( Sa ) prediction was 12.44%. The experimental and simulation results of surface topography shown that the effect of work-hardened layer cannot be ignored in two-step milling Inconel 718, which is prone to work hardening. Graphical abstract: Unlabelled Image