Faculty Publications
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Item Characterization of Rapid Foam Castings Produced by Different Mold Making Processes(Springer Nature, 2020) Bhagchandani, R.K.; Ghodke, R.; Manivannan, R.; Negi, S.; Kapil, S.; Karunakaran, K.P.Rapid casting gives the opportunity to develop a new casting in days, not in weeks or months. Evaporative Pattern Casting (EPC) process gives flexibility to produce complex geometries by integrating several parts in single casting. The lead-time and cost involved in designing and fabricating the metal tooling for Expanded Polystyrene (EPS) pattern making can be overcome by using the Segmented Object Manufacturing (SOM) machine. This hybrid system of pattern making is explored with all sub-systems and a complicated EPS pattern is produced by this Rapid Prototyping system. Conventional EPC process is more complicated due to coating development, vacuum assisted metal pouring and vibration system for filling the cavities by unbounded sand. In the present work, different mold-making processes are explored to avoid complications of conventional process. The Green sand, No-bake sand, and Plaster of Paris molds are prepared using Rapid Prototyped EPS pattern to produce the castings. The castings are characterized by comparing the surface roughness, dimensional accuracy, hardness, and surface morphology. © 2020, Springer Nature Singapore Pte Ltd.Item Machine-learning-based optimization of hybrid electrochemical magnetorheological finishing process to achieve nano finishing on additively manufactured biomaterial(Taylor and Francis Ltd., 2025) Singh Rajput, A.S.; Das, M.; Kapil, S.Powder Bed Fusion-Laser Beam (PBF-LB) is a form of additive manufacturing that entails the incremental layering of materials to construct complex multi-layered structures. The precise comprehension of the temporal and spatial variations of the entire structure. Individual tracks, layers, and the molten pool are indispensable for regulating aberrant deposition patterns and fabricating targeted PBF-LB components. However, the PBF-LB fabricated parts’ poor surface quality is a significant challenge. The Hybrid Electrochemical Magnetorheological (H-ECMR) polishing technique integrates mechanical abrasion with electrochemical reactions to enhance the surface characteristics of parts created through additive manufacturing. Herein, the Magnetorheological (MR) is used as the polishing media, and its carrier medium is replaced with an electrolyte to enable an electrochemical reaction. In the present work, machine learning-based optimisation, i.e. Artificial Neural Network, is implemented to optimise the process parameters to attain maximum surface reduction. The average surface roughness (Ra) value of 12.56 µm is lowered to 34.56 µm on the Ti-6Al-4 V polished surface at optimised process parameters. Furthermore, the electrochemical reaction between the workpiece and the electrolyte forms a dense and consistent oxide layer on the polished surface, increasing the corrosion resistance of the PBF-LB fabricated part. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Item Solar-Driven additive Manufacturing: Design and development of a novel sustainable fabrication process(Elsevier Ltd, 2025) Hazoary, A.; Panwar, M.; Singh Rajput, A.S.; Kapil, S.Additive Manufacturing (AM) is revolutionizing industries by enabling layer-by-layer fabrication of complex components. Among AM techniques, Laser Powder Bed Fusion (LPBF) is widely used but is energy-intensive, limiting its sustainability. This study explores the potential of concentrated solar energy as an alternative heat source for sintering Thermoplastic Polyurethane (TPU) in a solar-powered 3D printing process. A custom-designed solar 3D printer, equipped with stepper motors and an Arduino UNO for precise control, was utilized to evaluate critical process parameters such as feed rate, hatch spacing, and layer thickness. The results indicate that feed rate and hatch spacing are pivotal to energy density, directly influencing sintering quality. Optimal sintering occurred at feed rates between 100–200 mm/min, which provided sufficient energy for uniform layer fusion, balancing surface finish and mechanical strength. Larger feed rates resulted in incomplete sintering and weaker parts, while a hatch spacing of 1.67 mm offered efficient pass binding with reduced build time. The study successfully demonstrated the fabrication of multilayer TPU structures using solar energy, achieving mechanical properties comparable to conventional LPBF techniques. This solar-powered approach underscores the potential for integrating renewable energy into additive manufacturing, offering a sustainable alternative to laser-based systems. Future refinements, such as dynamic solar tracking and real-time parameter adjustments, could further enhance its industrial viability. By leveraging renewable energy, this research represents a significant step toward eco-friendly manufacturing solutions, reducing energy consumption and carbon footprint while maintaining high-quality outputs. © 2025 International Solar Energy SocietyItem 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