Why are steel saucepans and tea kettles covered with copper on the outside and the bottom? what r the goals of having high-quality pans that are thick and tea kettles that are thin walled?
Yep I agree with Scamper. Copper pot would be toxic so lined with tin or stainless steel.
Stainless steel is less conductive than copper. However, steel will retain heat longer and thus be distributed more evenly. (hence the thick bottoms, but also for balance). Copper on tea kettles is ideal to bring water up to a boil rapidly but since your not really cooking food, temperature distribution or control doesn't really matter. Now if your cooking sensitive food, then it does matter. For example, the use of a double boiler is preferred for chocolates. Temperature and distribution is critical. As far as relatively inexpensive copper clad pots and pans such as Revereware? Well, I don't see a difference but perhaps they did some testing.
The issue is heat conduction. Copper trasferrs heat rapidly and therefore ensures uniform heat around the base or sides of teh pot. The thick walls can be two different purposes. Sometimes the steel is made in layers for the purpose of providing insulation. If a pot insulates heat then the heat will transfer in a steady manner and the need for constant fuel heat is reduced. Thus, if I want to simmer and can store some of the heat in the pot itself then I know it will transfer slowly because it has to go through the layers first. Secondly, the layers will transfer heat between them allowing for uniform heating and this avoids hot spots. Wash you pots with an acid. Lemon will clean copper very nicely. If you have to scrub then heat gently and use salt or baking soda as an abrasive. With a tea kettle you do not care about heat conduction past the point of the boil. when the boil arrives the job is done.
