Thermomechanical oscillations in material flow during high-speed machining

This paper presents a nonlinear dynamics approach for predicting the transi tion from continuous to shear-localized chip formation in machining. Experi ments and a simplified one-dimensional model of the flow both show that, as cutting speed is increased, a transition takes place from continuous to sh ear-localized chip formation in the flowfield of the material being cut. In itially, the process appears to be somewhat disordered. With further increa ses in cutting speed! the average spacing between shear bands increases mon otonically, and the spacing becomes more regular and asymptotically approac hes a limiting value that is determined by the cutting conditions and the p roperties of the workpiece material.