Directed Energy Deposition Process Simulation to Sustain Design for Additive Remanufacturing Approaches

Abstract

Additive Manufacturing processes based on metal deposition are continuously evolving due to the extensive application potentials. Currently, they present a widespread use in manufacturing of large parts and constructions, as well as reparation of damaged components. A promising application is the Remanufacturing of existing components to produce functional design variants. A key phase for its development is the study and control of residual stress and deformations induced by the process. In fact, thermal gradients and cooling rates are more intensive than those related to the other metal additive manufacturing processes and their effect impacts on functional and assembly product requirements. This work provides the study of a laser-based Direct Metal Deposition process, supported by numerical simulation and experimental validation. The aim is to set up a framework for reliable simulations to drive the design of high performance components, which are optimized with respect to both product and process requirements. Process planning and deposition strategies highly affect heat dissipation and thermal cycles, thus, predictive techniques can be embedded in integrated product-process design approaches to avoid flaws and contain components shrinkage and deformation. The process is developed by building specific specimens, performing thermo-mechanical simulations, and comparing 3D capturing result and computed result. The simulation phase can thus be considered as a key step to structure a Design for Additive Remanufacturing workflow. Further developments concern the application of such approaches to the design of high performance components to be produced by Directed Energy Deposition process.