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Author: search.filters.author.Senthil Murugan, S.S.Subject: search.filters.subject.Dispersions

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    Effect of piezoelectric ceramic on natural frequency, structural, and thermal properties of additively manufactured PLA/BTO composite structure
    (Elsevier Ltd, 2025) Senthil Murugan, S.S.; Kattimani, S.
    This study investigates the fabrication and characterisation of filaments and 3D-printed samples using polylactic acid (PLA) and PLA/BTO (Barium Titanate) composites via fused deposition additive manufacturing (FDAM). PLA/BTO composite filaments were prepared by blending PLA granules with BTO particles using hot extrusion. Samples were 3D printed under controlled parameters and analyzed for dynamic, thermal, and structural properties. The inclusion of BTO significantly enhanced natural frequency (11 Hz-first peak) and structural rigidity compared to pure PLA (8 Hz-first peak), particularly under cantilever beam configurations. Microstructural analysis via optical and field emission scanning electron microscopy (FESEM) revealed uniform particle dispersion and good layer adhesion in composites with a peak width of 340 ?m. Energy-dispersive X-ray diffraction (EDS) study insisted that the presence of BTO improves functionality with minimal reinforcement with other trace elements. X-ray diffraction (XRD) confirmed increased crystallinity in PLA/BTO samples and improved alignment of the crystalline regions post-FDAM process, while Fourier transform infrared spectroscopy (FTIR) demonstrated molecular interactions between PLA and BTO and highlights the structural modifications in the composite due to the act of BTO reinforcement as nucleating agent. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) highlighted enhanced thermal stability and modified crystallinity due to BTO incorporation. Printed PLA/BTO demonstrates the highest resistance to thermal degradation than pure PLA, with degradation onset at an elevated temperature. Results validate the suitability of PLA/BTO composites for applications requiring tailored dynamic, thermal, and structural properties, emphasizing the FDAM process's potential for advanced material development. © 2025 Elsevier Ltd and Techna Group S.r.l.
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    Investigation of dielectric properties and shore hardness of 3D-printed PLA core sandwich disc with functional ceramics surface cladding
    (KeAi Publishing Communications Ltd., 2025) Senthil Murugan, S.S.; Kattimani, S.; Bharadwaj, N.
    Poly-lactic acid (PLA), a popular biodegradable polymer for 3D printing, has limited dielectric strength and surface hardness, restricting its use in advanced electronic and structural applications. Existing enhancement methods are often complex or yield inconsistent results. Therefore, a straightforward and scalable approach is necessary to enhance the properties of 3D-printed PLA. This study aims to explore the enhancement of the dielectric and surface hardness of printed PLA discs through surface cladding using nano-functional ceramics and graphene for next-generation multifunctional applications. PLA discs were fabricated via Fused Deposition Modelling (FDM) and subsequently cladded using hand layup with Araldite resin as a binder. Cladding materials included cobalt ferrite (CF), barium titanate (BTO), and graphene (Gr), individually and in combinations. Dielectric properties—capacitance, impedance, dielectric constant, dielectric loss, dissipation factor, and AC conductivity—were analyzed using an impedance analyzer, while surface hardness was measured using a Shore-D durometer. Results revealed that cladding led to uniform particle dispersion with effective surface bonding, improved dielectric performance, and significantly enhanced surface hardness. The CF + BTO + Gr combination exhibited superior dielectric behaviour, balancing high polarization with low energy dissipation, while BTO contributed to an enhanced dielectric constant and graphene improved charge transfer. All cladded samples showed frequency-dependent dielectric responses, with stability at higher frequencies. The highest surface hardness was achieved with CF + BTO, attributed to rigid, uniform reinforcement. © 2025 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltdé This is an open access article under the CC BY-NC-ND license. http://creativecommons.org/licenses/by-nc-nd/4.0/