Additive and subtractive hybrid manufacturing is one of the key technologies for aerospace manufacturing at present. Owing to the rotational degrees of freedom provided by five-axis machining center

the build direction can be continuously changed during additive manufacturing (AM) process

which can theoretically eradicate support structure. However

the introduction of multi-axis motion capacity increases the solution space

which poses great challenge for finding the solution of the process. In view of the above problem

a multi-axis AM process planning method based on centroid axis was proposed. On the basis of the definition of the centroid axis

the extraction method of centroid axis with “columnar” feature was studied

and sliced perpendicular to the centroid axis direction. Accordingly

the volume decomposition constraint was constructed. The slice position that dissatisfies the constraint was searched from the bottom to the top

where the part model was decomposed

and the direction of the centroid axis was used as the new build direction. The search was continued until the decomposition was completed. Finally

the part models are designed

and the feasibility of the method is verified through experiments

and support-free additive manufacturing of parts is realized.