Executive Summary : | Origin of the Proposal: Additive Manufacturing (AM) is an automated process technology, which is capable of producing 3-D objects directly from 3-D CAD data. The process nullifies the need of any specialized tooling, and the products are realized via successive addition of materials. AM offers significant design freedom and flexibility, compared to that of “Subtractive” and “Formative” shaping techniques. Recent improvements in laser and electron beam-based AM equipment facilitates development of complex contoured digitally Manufactured, i.e., “e-manufactured” parts, using powder bed or wire feed based systems. So, additive route offers promise to perform "Innovative Manufacturing" in true sense, in the present era when product complexities and aesthetic demands are on all-time high. In view of the above, the proposed research proposal offers promise to gain in-depth understanding and subsequent process development in case of additive manufacturing of Inconel 718 alloy via developing accurate CFD and Phase Field based numerical models. It should be noted here that, Inconel 718 is one of the most important superalloys being used in the aerospace and gas turbine engines, owing to its good high-temperature strength, high resistance to creep deformation and corrosion resistance. Key words: Additive Manufacturing (AM), Laser Powder Bed Fusion (LPBF), Directed Energy Deposition (DED), IN 718 superalloy, CFD modelling, Phase Field modelling, Molecular modelling. Objectives: 1. Development of multiphase, multiscale CFD model of solidification transport phenomena involved in case of LPBF and DED based Additive manufacturing of IN718 superalloy powder to grab insight into the process physics as well as to optimize the process variables. 2. Phase field and Molecular dynamics based simulation of solidification microstructure formation, in case of LPBF and DED, considering flow field predicted by the CFD model. 3. Estimation of boundary, initial conditions, and input parameters such as cooling rate in case of single and multi-layer LPBF and DED based numerical experiments via CFD model and subsequent prediction of microstructure adopting phase field and molecular modelling techniques, in coupled manner with thermodynamic and mobility databases. 4. Simulation of columnar to equiaxed transition of primary grains and back to the columnar shape during LPBF and DED, at the onset of changed scanning strategy and subsequent change in orientation of thermal gradient/solidification direction, adopting CFD, Phase Filed as well as Molecular modelling techniques. |