Chatter Identification of Face Milling Operation via Time-Frequency and Fourier Analysis

Abstract

Chatter is generally defined as self-generated vibrations from the interaction between tool and workpiece. It is the most critical vibration in machining operations and can decrease the surface quality and cause the premature tool wear. Chatter creates erroneous vibrations on the workpiece surface. However, even though the spatial response of chatter is still bounded, its frequency response would become unstably broadband, emitting high-pitched sounds. The deterioration in both time and frequency domains implies that chatter is a route-to-chaos process. To capture the time-frequency characteristics of chatter, instantaneous frequency is applied to extract the relevant force vibration of machining chatter, and the energy ratio approach is used to develop a discrete stability lobe diagram of a face-milling operation. The proposed method is validated by measuring the surface roughness of the workpiece.