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Item Effect of Wire-EDM textures on corrosion performance of Bio-Degradable Mg alloy(Elsevier B.V., 2024) Aswith Babu, I.; Kumar Manjhi, S.; Sekar, P.; Narendranath, S.; Balan, A.S.S.Magnesium (Mg) is the most suitable material for biodegradable implant applications owing to its nontoxic behaviour and comparable Young's modulus to human bone. However, poor corrosion resistance limits its application. Therefore, surface texturing can be a more suitable and cost-effective technique to mitigate these issues. Hence, wire electric discharge machining (WEDM) is used to create various textures (wavy texture, microchannels, and micro-pillars) and investigate their influence on the corrosion resistance of Mg-Zn-Ca alloy. The results revealed that micropillar texture exhibited significantly lower surface roughness (Ra = 1.049 µm) and a higher contact angle indicative of hydrophobicity (130.3°), resulting in superior corrosion resistance (corrosion rate: 0.816 mm/year) compared to other textures and standard WEDM surfaces. These findings suggested that textured surfaces generated through WEDM hold the potential for enhancing the corrosion resistance of biodegradable Mg implants. © 2024 Elsevier B.V.Item Effect of age hardening precipitates on the corrosion performance of laser Powder-Directed energy deposited CuNi2SiCr(Elsevier B.V., 2024) Urs, S.S.; Thanumoorthy, R.S.; Aswith Babu, I.; Doddamani, M.; Bontha, S.; Balan, A.S.S.This study explores Laser Powder ? Direct Energy Deposition (LP-DED) processing of CuNi2SiCr and the effect of heat treatment on corrosion behavior. The findings pave the way to increasing the life of the components and the possibility of refabrication upon failure. LP-DED manufactured CuNi2SiCr was subjected to solution treatment followed by age-hardening at 500? for 1,3,5 and 7 h. The microstructure analysis showed the formation of Cr3Ni precipitates due to a higher cooling rate in the LP-DED process. Upon aging, Ni3Si, Ni2Si, and CrSi2 precipitates evolved. Due to the Orowan phenomenon, microhardness increases with the aging time as the number of precipitates along the grain boundary increases with the aging time. The 5-hour aged sample exhibited the best corrosion resistance due to precipitation coherency in the matrix and the medium-sized precipitates with uniform precipitation-free zones (PFZ) in the grain boundary. © 2024 Elsevier B.V.Item Unveiling the role of heat treatment approaches in tailoring corrosion performance of laser powder-directed energy deposited SS304(Elsevier B.V., 2025) Sasindran, J.; Narayanan, J.A.; Babu, I.A.; Balan, A.S.S.; Hebbar, H.S.; Bontha, S.This study investigates the effect of different post-processing heat treatment approaches on the corrosion behavior of Laser Powder-Directed Energy Deposited (LP-DED) SS304. Samples were fabricated using optimized LP-DED parameters: laser power of 400 W, scan speed of 800 mm/min, feed rate of 4 g/min, 0.6 mm beam diameter, and 33 % track overlap.Electrochemical analysis revealed significant differences in corrosion performance depending on the applied heat treatment approach. This treatment resulted in changes to residual stress, microstructure, and oxide layer characteristics which together influence the corrosion rate (CR). The stress-relief annealed (SRA) samples significantly improved corrosion resistance by up to 90 % compared to the as-built condition, while preserving the fine microstructure formed during the LP-DED process and maintaining a stable protective oxide layer. Solution treated and different quenched samples exhibited varying CR depending on the cooling rate and resulting coarse grain structure. These findings highlight the significant influence of post-processing heat treatments on corrosion behavior and microstructural characteristics. © 2025 Elsevier B.V.Item Investigating the role of WEDM surface texturing in the degradation and biocompatibility of Mg–Zn–Ca alloy(KeAi Publishing Communications Ltd., 2025) Aswith Babu, I.; Sekar, P.; Prabhu, A.; Narendranath, S.; Balan, A.S.S.Magnesium (Mg) alloy-based biodegradable implants are gaining popularity for their low density, high strength, and biocompatibility. The corrosion and wear performance of Mg is poor in physiological environments, leading to premature failure. Surface modification, particularly through surface texturing, reduces the effective contact area of Mg–Zn–Ca alloy with corrosive media and tribological partners, potentially optimizing its degradation kinetics and cytocompatibility. Wire Electric Discharge Machining (WEDM) offers a stable oxide layer on the surface, unlike laser surface texturing, which may thermally damage the Mg alloy. In this study, three types of textures, mainly Wavy Texture (WT), microchannels (MC), and micropillars (MP), were created using WEDM on the Mg–Zn–Ca samples, and their corrosion, wear, cytotoxicity, and cell adhesion performance were evaluated. Texturing on the surface of the samples enhanced the corrosion performance, from 3.14 mm/year for the untextured sample to 0.98 mm/year for the micropillar textured sample, representing a 68.8 % reduction. This improvement after texturing is attributed to the superior surface finish (1.049 ?m) and increased hydrophobicity (130.3°), equating to a 50.8 % improvement. The coefficient of friction (COF) value decreased from 0.364 for an untextured sample to 0.208 for microchannels, a 42.9 % reduction, due to the entrapment of debris in the textures and effective heat transfer. The samples' cell adhesion and cell viability have been improved after texturing. The combination of cytocompatibility, appropriate mechanical properties, and a reduced bio-corrosion rate highlights the potential of this surface texturing method, utilizing WEDM, as a promising approach to enhance biodegradable implant materials. © 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 license. http://creativecommons.org/licenses/by/4.0/