Force prediction models for helical end milling of nickel-aluminium bronze

Nickel-aluminium bronze is used widely in seawater environment. The mechanistic method and analytical method to predict helical end milling force are briefly described and compared. The mechanistic approach is shown to depend on milling force coefficients determined from milling tests. By contrast, the analytical method is based on a predictive machining theory, which regards the workpiece material properties, tool geometry, cutting conditions and types of milling as the input data. Each cutting edge of the helical end cutter is discretized into a series of infinitesimal elements along the cutter axis and the cutting action of which is equivalent to the classical oblique cutting process. Thus, the cutting force components applied on each element can be calculated using a predictive oblique cutting model and the total instantaneous cutting forces are obtained by summing up the forces contributed by all cutting edges. The equation of equivalent plane angle is derivation through coordinate transformation. Experiments on machining nickel-aluminium bronze under different cutting conditions were conducted to validate the proposed model.