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Item Interrupted metal deposition wire arc additive manufacturing to fabricate objects with trailered microstructures(Elsevier B.V., 2025) Singh, C.P.; Tiwari, V.; Kumar, A.; Kapil, S.; Singh, S.S.; Singh Rajput, A.S.Advances in additive manufacturing have enabled innovative approaches to creating materials with tailored properties. This study presents Interrupted Metal Deposition in Wire Arc Additive Manufacturing (IMD-WAAM) for fabricating thin walls of Functionally Graded Materials (FGMs). By controlling heat input during deposition, IMD-WAAM precisely modulates microstructural evolution. Characterization techniques, including Optical Emission Spectroscopy (OES) for composition analysis, Field Emission Scanning Electron Microscopy (FESEM), and Electron Backscatter Diffraction (EBSD) for grain-level insights, along with Continuous Cooling Transformation (CCT) diagrams from JMatPro, revealed distinct microstructural zones. Continuous deposition showed coarse ferritic structures, while a 5-second Inter-Drop Cooling Time (IDCT) produced refined ferritic and bainitic structures. These results demonstrate IMD-WAAM's ability to achieve seamless property gradation, making it a transformative method for aerospace, biomedical, and other applications requiring customized material properties. © 2025 Elsevier B.V.Item Hybrid wire arc directed energy deposition and machining approach for realizing density-based functionally graded materials with enhanced strength-to-weight ratios(Elsevier Ltd, 2025) Sarma, R.; Singh Rajput, A.S.; Kapil, S.; Joshi, S.N.Wire Arc Directed Energy Deposition (WADED), a high-deposition-rate Additive Manufacturing (AM) technique, enables the rapid fabrication of near-net-shape metallic components. However, achieving Functionally Graded Materials (FGMs) with density variations within the same material remains challenging. This study introduces a novel Hybrid WADED (H-WADED) process to fabricate mono-material FGMs with engineered density gradients tailored for applications in aerospace, nuclear energy, and electromagnetism. In this method, each layer is deposited using WADED, followed by face milling and robotic drilling to introduce controlled holes. The diameter and spacing of the holes are designed to achieve the desired density gradient, enabling up to a 10 % reduction in mass. Experimental results showed 2 mm diameter holes as optimal, minimizing material flow and distortion while improving the strength-to-weight ratio. This innovation also enhances thermal dissipation capabilities, making the components suitable for high-stress environments. Performance evaluation of the fabricated FGMs revealed a 26.2 % reduction in thermal conductivity and significant mitigation of residual stresses due to stress redistribution around the holes. Under compressive loading, the samples exhibited a maximum load capacity of 200 kN. Although tensile strength was reduced by 19.6 % compared to solid samples, elongation remained unaffected, highlighting the structural integrity of the components. This work demonstrates an effective method to fabricate density-based FGMs, providing a practical pathway for developing advanced, lightweight, and thermally efficient components for critical industrial applications. © 2025