Sheet metal is formed from thin and flat pieces. The fundamental forms are used in metalworking and involve various processes to convert sheet metal into different shapes for a large variety of finished parts such as aluminum aircraft body panels. There are many different metals that can be made into sheet metal. Aluminum, brass, copper, cold rolled steel, mild steel, tin, nickel and titanium are just a few examples of metal that can be made into sheet metal. Key to the formability of sheet metal is its ductility. Typical forming processes include：
‧ Stretch Forming
‧ Drop Hammering
‧ Bending
‧ Deep Drawing
‧ Hydro Forming
‧ Roll Forming
‧ Hot/ Super-plastic Forming
Stretch Forming is a process where sheet metal is clamped around its edges and stretched over a die or form block. This process is mainly used for the manufacture of aircraft fuselage skins, frames, stiffeners and wings panels.
Hydro forming (or hydramolding) is a cost-effective way of shaping malleable metals such as aluminum into lightweight, structurally stiff and strong pieces. One of the largest applications of hydroforming is the aerospace industry, which makes use of the complex shapes possible by hydroforming to produce stronger, lighter, and more rigid unibody structures for aircraft.
