Investigation of Nickel Effects on Matt Cast Iron Enamel

Abstract

Cast iron is the generic name for iron-carbon alloys containing more than 2% carbon content. It can melt at low temperatures compared to steel and has low cost. The surfaces of cast irons, which can be used in many areas from construction to kitchen equipment, are coated with enamel to prevent corrosion, increase wear resistance and easy to clean. Enamels are glassy coating materials obtained by adding various oxides such as Al2O3, B2O3, ZrO2, NiO, CoO into SiO2. The raw materials used and the oxides formed during production have a direct effect on the end product properties of the enamel. NiO and CoO are the most essential oxides affecting the bonding performance of the enamel to the metallic surface. Although NiO has little effect on glassy structures, it improves the adherence performance. It is also effective on the aesthetic appearance of the enamel. It gives a dark color to the enamel and prevents fish scale defects, with the latest regulations, the use of nickel in enamels has been restricted for health and environmental safety reasons. For this reason, studies have started to develop a new generation of nickel-free enamels suitable for regulations. In this study, the development of enamel that can be applied to cast iron surfaces having a matt appearance that does not contain nickel and the effect of nickel on enamel properties were investigated. In the existing frit compositions, new frit recipes were prepared, which did not contain nickel and were applied to cast iron surfaces by wet application method. Heat microscopy analysis of prepared frit was performed. Microstructure, chemical abrasion resistance, color properties, surface properties, coating adherence performance, and the effect of nickel on these properties were investigated. 

Keywords

• enamel,cast iron,nickel free,metal coatings

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