Singh, C.P.Tiwari, V.Kumar, A.Kapil, S.Singh, S.S.Singh Rajput, A.S.2026-02-032025Materials Letters, 2025, 389, , pp. -0167577Xhttps://doi.org/10.1016/j.matlet.2025.138297https://idr.nitk.ac.in/handle/123456789/20222Advances 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.BainiteBainitic transformationsField emission microscopesHard facingMicrostructural evolutionSurface dischargesWire3-D printing3D-printingContinuous cooling transformationFerritic structuresMetal additive manufacturingMetal additivesMetal depositionMicro-structuralWire arcXDSOptical emission spectroscopy