CHATTER ONSET IN NON-REGENERATIVE CUTTING: A NUMERICAL STUDY

A non-linear model of non-regenerative cutting is analyzed. When damped, the model has a stable fixed point for small values of chip thickness. As chip thickness is increased, the fixed point becomes unstable via a sub-critical Hopf bifurcation. This transition corresponds to the onset of chatter. When dynamic noise is added to the system, chatter onset can occur in the sub-critical parameter region, although chatter-free cutting is predicted by the stability analysis of the fixed point. A noisy bifurcation diagram is compared qualitatively to a diagram obtained experimentally in regenerative cutting. Similar features regarding the onset of chatter are observed in both diagrams.