Tool wear and surface topography shaping after TPl multi-axis milling of Ni-based superalloy of the torus milling cutter using the strategy of adaptive change of the active cutting edge segment

Abstract

This paper details an investigation of the process of multi-axis high-speed milling of the surface of Ni-based superalloy Inconel 718 parts used the torus milling cutter. Presents the issues and development of the own models of the multi-axis milling in a kinematic variant of the TPl (Tool Pulling) type in terms of tool wear. Because the cutting speed in finishing high-speed milling is the parameter with the greatest influence on tool life and surface roughness, the dependence of the variation of the cutting speed at the torus part of the cutter was first determined as a function of the distance from the tip point along the axial direction and the geometrical parameters of the torus. A model for multi-axis milling of the TPl type was developed and described in a simplified manner, which forms the basis of an own ACACES strategy for segmenting the cutting edge of a torus milling cutter. The adaptation of a given segment to the active cutting edge during machining was based on tool wear and kinematic roughness criteria. Simulations and experiments of multi-axis milling were carried out, and the necessary analyses were performed. In this paper, in addition to testing an in-house strategy for multi-axis milling used the torus milling cutter, the problem of defining the cutting speed in relation to the nominal diameter and effective diameter of the tool is investigated for the first time. In addition, wear measurement was carried out using an in-house methodology, taking full advantage of the capabilities of the multi-axis machining centre, which significantly reduced measurement time and positively influenced the effectiveness of tool life assessment. Using the own ACACES strategy of the multi-axis surface milling of parts made of Ni-based superalloys, an almost fourfold increase in torus cutter life was achieved compared to the conventional strategy, while maintaining the required machined surface roughness parameters.