Chatter Avoidance by Spindle Speed and Orientation Planning in Five-Axis Ball-End Milling of Thin-Walled Blades

Selecting suitable cutting conditions is crucial in maintaining chatter stability and achieving acceptable surface quality. However, the selection of a constant set of cutting parameters is not feasible due to the time-varying dynamics of highly flexible thin-walled blades. This paper presents an optimal selection of tool orientation and spindle speed along the tool path as the metal is removed during the ball-end milling of blades. The effects of tool orientation and speed on the mechanics and dynamics of the ball-end milling process are formulated. Test case simulations are used to demonstrate the impact of tool orientation and speed on chatter stability and forced vibrations. The proposed algorithm identifies the optimal spindle speed and tool orientation by continuously updating the workpiece dynamics as a function of time and tool position to achieve improved stability and surface quality. Stability simulations are conducted to assess the optimization approach's performance, and the results are compared with experiments by machining a series of thin-walled twisted fan blades.