The effect of built-up edge on the cutting vibrations in machining 2024-T351 aluminum alloy

Abstract

Modern advanced machining processes often require the automatic monitoring of tool condition and machining performance, such as the cutting vibrations and chatter, the cutting forces, tool wear, the machined surface quality, and built-up edge (BUE). The BUE is often generated on the tool rake face in machining ductile metals and alloys at low to moderate cutting speeds. The previous research focused on the effects of the BUE on the cutting forces, tool wear, the machined surface roughness, and so on. The present study closes the research gap by establishing a quantitative relationship between BUE formation and cutting vibrations. A set of cutting experiments covering a wide range of cutting conditions was performed on an aluminum alloy commonly used in many industries. The vibration signals generated from machining were analyzed in both time and frequency domains. The results show that there exist three distinct BUE regions that are characterized by different patterns of cutting vibrations. The vibration amplitude is influenced by the cutting speed, the feed rate, and their interaction. It is proposed and shown that kurtosis, a statistical tool, can be used to distinguish between “steady” and “unsteady” BUE formation that is associated with different patterns of cutting vibrations. It is also shown that the frequency analysis using spectra provides more insights into various frequency components.