Research on the multi-physical coupling characteristics of the machine tool and milling process based on the systematically integrated model

Abstract

Good machine tool precision and a stable milling process are important foundations for obtaining high-quality qualified parts. During the machining process, the machine tool and the milling process will impact each other, and further jointly affect the motion accuracy as well as part quality. This paper makes a deep analysis of the machine tool and milling process from a new perspective, which regards the machine tool and milling process as a coupled entirety, and studies the interaction between them from a systematic perspective. By establishing a systematically integrated model of the ball screw feed system and milling process, the multi-physical simulation of the whole system is realized with the consideration of multi-source harmonics. The electrical-magnetic-mechanical-kinematic coupling characteristics between the machine tool and the milling process are investigated based on the established model and experiments. The research results show that the servo system and the milling process are two major harmonic sources in the system that generate low-medium frequency and medium-high frequency harmonics, respectively. As the machining process progresses, these harmonics will be transmitted and coupled through the servo motor, mechanical structure, and feedback signals, leading to the fluctuation in the motion of the worktable and the influences on the surface quality of the final part. A type of part surface defect that can only be explained by integrated analysis of the whole system is also demonstrated. The research work indicates that the machine tool and milling process is an integrated system with strong coupling characteristics. It's of great significance to study them from a systematic perspective.