Shaped metal deposition processes

Abstract

The shaped metal deposition (SMD) process is a novel manufacturing technology which is similar to the multi-pass welding used for building features such as lugs and flanges on components [1–7]. This innovative technique is of great interest due to the possibility of employing standard welding equipment without the need for extensive new investment [8, 9]. The numerical simulation of SMD processes has been one of the research topics of great interest over the last years and requires a fully coupled thermo-mechanical formulation, including phase-change phenomena defined in terms of both latent heat release and shrinkage effects [1–6]. It is shown how computational welding mechanics models can be used to model SMD for prediction of temperature evolution, transient, as well as residual stresses and distortions due to the successive welding layers deposited. Material behavior is characterized by a thermo-elasto-viscoplastic constitutive model coupled with a metallurgical model [6]. Two different materials, nickel superalloy 718 [6] and titanium Ti-6Al-4 V 28/5/2014 Shaped Metal Deposition Processes - Springer http://link.springer.com/referenceworkentry/10.1007/978-94-007-2739-7_808/fulltext.html 2/15 [7], are considered in this work. Both heat convection and heat radiation models are introduced to dissipate heat through the boundaries of the component. The in-house-developed coupled thermomechanical finite element (FE) software COMET [10] is used to deal with the numerical simulation, and an ad hoc activation methodology is formulated to simulate the deposition of the different layers of filler material.