Development of manufacturing strategies by hybridizing WXAM process and 5 axis machining of complex shapes – AWESOME

Producing complex shaped parts with high added value by hybridizing WXAM and 5-axis machining processes is a major challenge that may contribute to the competitiveness of companies. This requires obtaining rough parts of "near net shape" quality to minimize machining operations and requires controlling the parameters and execution of the WXAM process on 6-axis anthropomorphic robots or 5-axis machine tools. Finally, this necessarily relies on the development of a digital chain integrating additive manufacturing processes and which is lacking, on a topological division of parts into entities and an optimal sequence of operations, based on thermal, geometrical and kinematical constraints as well as new trajectories.
Thus, the objective of the AWESOME project is to contribute to the development of an integrated hybrid manufacturing process for the production of complex shaped parts. More specifically, the aim is to develop manufacturing strategies by hybridization between Directed Energy Deposition processes and 5-axis machining as well as the key elements of the associated digital chain for producing parts such as stainless-steel hydraulic turbine blades.
To achieve this goal, the project aims to address the following scientific and technological challenges: 1) optimize the topological decomposition of the part into entities and the hybridization between additive and subtractive manufacturing, 2) synthesize the manufacturing parameters to obtain a "near net shape" target geometry, 3) model the influence of disturbances during the execution of the WXAM trajectories, and 4) perform closed-loop control of the process trajectories.
The expected results of the AWESOME project are: 1) the definition of additive entities and algorithms to define the trajectories of the associated manufacturing processes and a multicriteria analysis method to optimize their scheduling with the machining operations to form the manufacturing sequence; 2) a model to determine the parameters of the WXAM processes from the geometries of the "near net shape" entities to be produced; 3) an experimental set-up for in-process acquisition of the beads’ shape and in-situ acquisition of the additive manufacturing entities ; 4) Numerical treatments of measurements in a feedback loop towards the design of the process and the control of the process in real time ; 4) a defect library of parts produced in 5-axis WXAM caused by the thermal and kinematic behaviors, associated with geometric models including defects.
The innovative character of the AWESOME project lies in the will to tightly integrate additive and subtractive processes and to cover not only the definition of the processes but also their execution on the production means. This is made possible by the integration of multidisciplinary skills (CAD/CAM, thermal modeling, multi-body kinematics, in-situ / in-process geometric measurements, control command) to obtain in fine an integrated hybrid manufacturing process as well as its digital chain through an industrial demonstrator.
The success of the project is therefore based on the complementarity between the academic and industrial partners, on the experience of the actors in joint collaborative projects and on the recruitment of three Ph.D. students in the project. The first one will be in charge of developing "near net shape" additive manufacturing entities and optimizing the hybrid manufacturing sequence; the second one will be in charge of transforming an entity into bead geometry and process parameters and guaranteeing their correct formation during the process; the third Ph.D. student will develop an in-situ measurement method by image correlation and the numerical processing in order to continuously readjust the deposition or machining trajectories during the manufacturing process.