Investigation on CaO-SiO 2 -CaF 2 -SrO Based Electrode Coating System on High-Temperature Wettability and Structural Behaviour for Power Plants Welds

This research examines the high-temperature wettability and structural behavior using a CaO-SiO 2 -CaF 2 -SrO-based coating system for power plant welds. The wettability properties, including adhesion energy, contact angle, surface tension, and spreading area, were investigated. Twenty-one distinct electrode coating formulations were developed using the extreme vertices technique. Circular pellets were prepared from powder sample and heating inside the furnace at a temperature of 1200 °C at a constant heating rate to determine the contact angle between liquid/solid interfaces. Phases and structural behavior of coating samples were measured using X-ray diffraction and Infrared spectroscopy. Young’s & Boni’s equations are used to calculate the surface tension value for twenty-one coated samples using the calculated contact angle. Adhesion energy for twenty-one coated samples is calculated using Dupre’s equation. The developed regression model estimates the influence of primary constituents and interaction on the calculated wettability characteristics. Binary mixture of CaO.SrO, CaF 2 .SrO, CaF 2 .SiO 2 , and SiO 2 .SrO is the most effective and has an increasing effect on contact angles. Coating number 3, 5, 6, 8,10,12,13, 17, 19, and 21 gives better wetting behavior and spread area due to the low value of contact angles. The individual ingredients and binary interaction of CaO.CaF 2 affects surface tension significantly. Ternary mixtureCaO.CaF 2 .SrO, CaO.SiO 2 .SrO, and CaF 2 .SiO 2 .SrO has an increasing effect on adhesion energy.