Vitreous enamel coatings have been widely utilized to protect metallic substrates due to their exceptional properties, including wear resistance, thermal stability, and corrosion resistance. However, their brittle nature limits their mechanical performance under stress. Introducing a ductile second phase, such as metallic flakes, into the brittle enamel matrix. This approach enhances the mechanical reliability of the coating while maintaining its protective properties. 

316L stainless steel was selected due to its excellent corrosion resistance, high ductility, and thermal compatibility with enamel, making it an ideal reinforcing phase. Its inclusion enhances fracture toughness and crack resistance. The formulation changes, specifically the addition of 1 wt.% and 5 wt.% 316L flakes significantly improved mechanical strength by reducing brittleness and promoting energy dissipation during stress.   

The study focuses on characterizing the mechanical behavior of these composite coatings under various stress conditions, including four-point bending and indentation fracture tests. A simulation study was also conducted considering actual tank application scenarios. Advanced finite element analysis (FEA) tools were employed to investigate thermal stresses resulting from mismatched coefficients of thermal expansion among the base metal, enamel, and 316L stainless steel flakes. The study further examined residual stresses induced during the cooling phase after firing, along with elastic and plastic deformations, crack propagation behavior, and improvements in fatigue durability compared to baseline compositions. Additionally, coating thickness optimization was carried out to achieve an ideal balance between mechanical strength and material malleability. Density measurements of the vitreous enamel were also performed before and after the firing process, as they play a crucial role in controlling the application process and ensuring the quality of the final product. 

The goal is to develop a mechanically robust enamel coating suitable for domestic appliances.