Faculty Publications

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    Experimental analysis and optimization of plasma spray parameters on microhardness and wear loss of Mo-Ni-Cr coated super duplex stainless steel
    (Taylor and Francis Ltd., 2022) Gowdru Chandrashekarappa, M.; Pradeep, N.B.; Girisha, L.; Harsha, H.M.; Shettigar, A.
    Plasma spray coatings are one among the economic path to offer quick solutions for preventing the part (substrate) failures due to rapid wear. In the present work, Mo-Ni-Cr powder is used as a coating material on super duplex stainless steel to minimise the wear loss. The microhardness of the coating is affected by the factors (current, powder feed rate and standoff distance) of the plasma spray coating process. Taguchi method is followed for preliminary experimental plan, analysis, and to perform optimisation for maximum microhardness. The results showed that the current being the dominant effect followed by powder feed rate and standoff distance on the microhardness of coated samples. The optimised plasma spray condition resulted in the highest coating microhardness (i.e., 764.33 HV), which is 2.78 times higher than that of super duplex stainless steel (i.e., 275 HV). Taguchi experiments are conducted to know the factors (load, sliding speed and sliding distance) influence the wear loss of coated samples prepared for optimised plasma spray conditions. The applied load and sliding speed are found statistically significant, whereas the sliding distance is insignificant towards wear loss. The results of wear loss of the substrate (uncoated sample) and optimised condition of the coated sample are found equal to 18 mg, and 2.8 mg, respectively. © 2020 Engineers Australia.
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    A comparison of high temperature corrosion behaviour between uncoated, Ni-Cr-Mo and Ni-Cr-Al-Y coated 316 stainless steel in ZnCl2-KCl environment
    (Elsevier B.V., 2025) Pooja, P.; Vijayan, V.; Ravishankar, K.S.; Madav, V.
    High-temperature corrosion poses a significant challenge to the longevity and performance of materials in extreme environments. This study investigates the corrosion behavior of coated and uncoated 316 stainless steel (SS) in ZnCl2-KCl eutectic molten salt vapor at 600 °C. Contrary to expectations, the results indicate that uncoated 316 SS exhibits lesser corrosion compared to certain coated samples over prolonged exposure. Comprehensive analysis, including weight change measurements, electrochemical evaluations, and surface morphology examination, reveals the degradation mechanisms and the efficacy of coatings. Amongst the various materials used for study, NiCrMo coated 316SS showed least corrosion rate of 8.34 mpy and 3.2 mpy after 20 h and 100 h respectively. The findings provide insights into optimizing material protection strategies in harsh chloride containing molten salt environments. © 2025