Al-induced electroless process is used to fabricate Sn films on the mild steel substrates. The deposition reaction was performed by designing a Fe-Al galvanic couple where the optimum geometric area ratio between Fe-Al was 0.3. Additionally, NaBH 4 and NaH 2 PO 2 reducing agents were also added to enrich the deposit morphology and composition. The film surfaces were characterized by scanning electron microscopy, energy-dispersive x-ray spectroscopy and x-ray diffraction measurements. The analysis showed dense, uniform tin deposits with the presence of boron and phosphorous. The x-ray diffraction results confirmed the polycrystalline tetragonal structure with mostly (211) texture having an average 18 nm crystallite size. The anti-corrosion performance of these tin films has been studied by immersion in saltwater, open circuit potential measurement test, potentiodynamic polarization test, and electrochemical impedance spectroscopy. The effect of the coating thickness was also considered in anti-corrosion performance. The analysis showed the tin coated steel has commendable corrosion resistant property and the corrosion rate can be decreased up to 16 times with the addition of these coatings irrespective of the film thickness.

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The Himalayas form the Northern frontiers of the Indian subcontinent. Many streams originate in these mountain ranges and descend to the adjoining plains known as the Indo-Gangetic plains. The Himalayas presently experience immense stresses as a result of which multiple faults and shear zones traverse it. The signature of these large-scale structural elements on the surface can be identified in the form of lineaments. The Himalayas can be longitudinally divided into the Siwaliks, Lesser Himalayas, Middle Himalayas, and the Higher Himalayas, with each of these units being separated by active fault systems. Four significant trends of lineaments are observed in the area viz. NW-SE, NNW-SSE, NE-SW, and E-W. These trends also resemble with the preexisting subsurface deformational pattern of the study area.

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