A tin-plate is defined to be a thin sheet of iron or a steel alloy that is coated with tin. This helps prevent the steel from rusting. They are most commonly used to make cans and pots.
Iron can are electroplated with tin to prevent the cans from rusting. Tin is a metal that resists rust.
They're not - or not any more. When it was done (a century ago) it was to prevent the steel of the cans from rusting.
As it's name suggests, a popcorn tin is made of tin. Tin is a metal but almost no cans, or popcorn tins, were actually made of tin. Rather they were made of tinplate, which is a thin layer of tin over a steel can. Today, aluminum cans have largely replaced tinplate cans - the can is aluminum while the top of the can is still made of tinplate.
Steel cans coated with a thin layer of tin to prevent rusting of the steel. If the can contents are acidic a further layer of polyethylene is added to the inside surfaces.
The raw materials used to make drink cans are primarily aluminum and tinplate. Aluminum is used for the body of the can, while tinplate (steel coated with a thin layer of tin) is used for the can's lid and base. These materials are chosen for their durability, ability to be recycled, and cost-effectiveness.
Tin cans are coated with a layer of tin to prevent rusting of the underlying iron. When the coating is ruptured, the exposed iron is more susceptible to rusting due to the break in the protective barrier. The rusting process accelerates because the exposed iron is in direct contact with moisture and oxygen, which are necessary for rust formation.
No cans currently in wide use are composed primarily or wholly of tin; that term rather reflects the nearly exclusive use in cans, until the second half of the 20th century, of tinplate steel, which combined the physical strength and relatively low price of steel with the corrosion resistance of tin. Most cans are made from either aluminium or tinplate steel. For the most part, however, it is really a case of old habits die hard. It is just something which has stuck in the modern vernacular.
Painting will be a good option to prevent rusting.
Coating prevent the iron from contacting air and moisture. So it prevents iron from rusting.
Tinplate Packaging Market
If they where painted