Clad Cookware - Encapsulation of Aluminum or Copper With Stainless Steel

Encapsulated cookware is fairly new to the market and is exactly what its name implies. Encapsulation by definition is the action of covering or surrounding one material with another material for purposes like durability, chemical stability, heat distribution, weight reduction and so on.

This has become very popular in cookware and many of the more popular brands use this technique - typically referred to as clad cookware. A manufacturer may decide that a particular metal or metal alloy will not provide the properties they are seeking. Encapsulating combines two or more metals into a single material (similar to plywood) and as they combine properties change as well. Essentially, encapsulation tries to keep best properties of the original materials while minimizing the least useful.

The most common intent for encapsulation is to produce more even heat distribution in stove top cookware while at the same time minimizing the product's weight and the potential of chemical reaction with the food. Typically a sheet of aluminum or copper is surrounded by stainless steel. The aluminum or copper core provides even and quick heat distribution which stainless steel by itself does poorly. The stainless steel is inert so does not react with foods which aluminum and copper are prone to. The combination of even heat distribution along with an inert cooking surface and strong outer shell yields superior features for cookware.

The process by which the aluminum or copper core is encapsulated varies from manufacturer to manufacturer. Some use a technique very similar to the way a candle is made building one layer after another. Others use a technique of welding the edges of plates laid one top of another. And still others use enormous pressure to bond the layers together. In some of the more recent products, the outer layer of stainless steel is different from the inner layer. This allows the product to have magnetic features for induction stove tops while retaining the very hard and inert inner lining. The number of layers is usually three but higher end consumer and some commercial cookware can have four or five layers.

The clad cookware has replaced much of the older layered cookware such as copper bottom or tin lined aluminum. The earlier manufacturing process lined the more metal which had tendencies to react with foods with a thin lining of inert metal such as tin or welded a cooper bottom on to a stainless steel cylinder

The stainless steel bottom provides increased durability while the aluminum or copper core yields even heat distribution and the stainless steel inner lining provides the inert smooth surface for cooking. Encapsulating any cookware cab be expensive so some models encapsulate only those parts of cookware required. As an example, stock pots, some sauce pot or Dutch ovens and other pots and pans that only need heat across the bottom use cladding on the bottom. Frequently the edges of the different metal plates can be seen. Sauce pans, sauté pans, skillets and other that need heat distributed up the sides use this technique all the way to the edges of the cookware

Currently, encapsulation is used in producing cookware for induction cook tops. Induction uses electromagnetic fields to heat a ferrous or iron based material. This material completes the circuit with the stove top and is the only thing that gets hot. The cookware has to be able to hold an electromagnetic charge; this means it has to be able to be magnetized.

Many metals used for conventional cook tops were not designed with magnetic properties in mind but considerations for lightness, heat retention or appearance were more important. Now manufacturers are designing specifically for induction stove tops yet still retain the flexibility of moving cookware from stove top to oven and back. They are using a ferrous based stainless alloy for the outer layer to complete the electromagnetic circuit and use 18-10 for the inner layer for appearance and superior cooking features. This maintains the objectives of keeping pots and pans as light as possible, retains their attractive features and keeps their good looks.

Having these features work well together provides attractive and useful cookware that consumers appreciate and love.