An aluminum cot is the most widely available of cot frames. These cots are lightweight and resistant to corrosion, which makes them easy to transport and ideal for outdoor use.
All the major cot styles are available with an aluminum frame.
Aluminum vs steel
Aluminum is a softer metal than steel. Standard aluminum is 1/3 the weight of steel and has 1/3 the (tensile) strength of steel. Aluminum frames, however, can be designed to be plenty strong for heavy campers by using a heavier gauge and bracing.
Campers appreciate the lighter weight of an aluminum frame when transporting the cot. They also appreciate not having to worry about rust (corrosion) making the frame unsightly and eventually weakening the frame to the point of failure (bending or buckling).
Aluminum does corrode like steel, but the corrosion process causes a slight film of aluminum oxide to form on the exterior of the metal, which basically galvanizes the metal and protects it from any further corrosion. To the camper, it appears that the the metal has only lost its original shiny finish, but no further corrosion or damage to the frame occurs.
Aluminum-frame cots have no paint to chip or scratch, exposing the metal surface to moisture and causing corrosion. These cots can take a minor blow or scrape to the metal surface without worry.
The fact that aluminum only slightly corrodes means that an aluminum-frame cot can perform well for years with no fear of rust and corrosion causing the frame or legs to fail over time.
For the same amount of bulk, aluminum light-weight cots may weight half as much as steel cots.
You may ask, "Why not just use a lighter gauge of steel to make a lightweight cot?". Campetent suspects that, with exposure to outdoor moisture and temperature variation, light-gauge steel would more quickly deteriorate to the point of failure.
Heavy-duty aluminum cots
Heavy-gauge, tempered (hardened) aluminum is used for heavy-duty cots in order to keep the frame tubing from bending or buckling under the load (weight) of a large camper.
Another solution to reinforce aluminum is to insert a slightly-narrower steel tube into the aluminum leg tubing to use the extra strength of steel to support the aluminum leg against bending. These steel tubes are called steel inserts.
Aluminum frames often have steel connectors, which are flat brackets that hold moving pieces together. Aluminum is a relatively soft metal and a flat, two-dimensional shape would easily bend if exposed to side forces. Steel is used instead, because it is a much harder metal and can be fabricated to withstand bending forces even when flat.
Aluminum-frame cots are ideal for outdoor leisure-tent camping. The aluminum frame quickly seals itself against further corrosion, and light-weight aluminum cots are easier to transport than steel cots.
Light-weight aluminum-frame cots are available from a large number of manufacturers listed on the main camping cot page.