Development of an enhanced burr accumulation model during orthogonal cutting of nickel-based super alloy

Abstract

Burr size is a real issue in aeronautic for machining highly critical parts, such as broaching of turbine disks, it may affect the mechanical resistance of the part. However, the analysis and modelling of the burr formation and its accumulation is challenging due to the small concerned root area and the change of its shape after multiple cuts. In the state of the art, there is not much contribution on the burr mechanism during accumulation. To investigate this subject on nickel-based super alloy parts, an experiment with an in situ camera and LASER profilometer has been developed to follow the burr growth after multiple passes. Then, a phenomenological model of burr accumulation is formulated based on the description of a plastic hinge appearance during burr formations. It enables the modelling of burr height, root thickness and added material to the burr after each pass. Burr fracture occurrence is also discussed. This work proposes a new outlook on the burr formation mechanism and complete the models previously developed in the known literature.