Influence of tool wear on the mechanism of chips segmentation and tool vibration

Abstract

The tool wear has a significant impact on the cutting process and therefore tool wear monitoring is especially important for building intelligent machine tools which are capable of assessing their own states and reacting to important changes. This approach is based on the assumption that there exists a relationship between the spectrum of high-frequency vibrations measured on tool holder, in immediate vicinity of the cutting zone, and the tool wear degree. The wear causes changes in tool tip geometry, which has significant influence on the process of chip forming. At the same time, the erratic nature of chip forming process excites the cutting zone, generating a very broad spectrum of vibrations. Due to high input energy, these vibrations are very intensive, and spread through the entire machining system. In the paper, experimental results are shown which pertain to the relationship between the power spectral density (PSD) within 5 kHz to 50 kHz interval.