The Mohs hardness of tin is about 1.5, which means that it is easily affected by external friction. During long-term use, the tin layer may become thinner due to wear or even fall off completely.
As mentioned above, the melting point of the tin layer is much lower than that of the steel. If the tinplate sheet is heated directly, the tin layer will melt before the steel substrate reaches the melting temperature, which will cause the tin layer to be lost and lose its anti-corrosion function.
The coating of tinplate is tin, while the coating of TFS is chromium. This is the most significant difference between the two. The anti-corrosion performance of tin mainly relies on its chemical inertness, while chromium relies more on its chemical stability and the protection of the oxide film.
High-quality electrolytic tinplate sheet should have a high-quality low-carbon steel substrate and a pure tin-plated layer: through composition analysis and surface inspection, ensure the purity and uniformity of the raw materials.