Hydroforming is a specific method used to shape ductile metals, such as aluminum, stainless steel, low alloy steels, and brass into particular shapes using a combination of die pressing and fluid injection. Hydroforming transforms the metal into a desired shape without the use of heat, which allows the metal to retain a high level of strength.
The process of forming metal using the hydro-forming process is fairly simple. A machine has a mold for the desired finished shape of the part. The piece of metal is placed inside the machine at room temperature. The machine is then closed and hydraulic fluid is injected into the mold. The pressure from the fluid causes the metal to bend to match the contours of the mold. After the metal achieves the desired shape, the part is removed from the mold and the process is repeated.
This method of shaping metal is most commonly used in the automotive industry. High-end sports vehicles and other high-performance vehicles use the water-based die forming process to create strong, light, and rigid metal frames for high-performance work.
There are two main forms of hydro-forming. Sheet hydro-forming created shaped sheet metal. This process has been in use since the 1950s, and was originally designed to shape sinks and kitchen faucets. In combination with the pressure and liquid, sheet forming also uses cutting dies that shape the flat metal pieces. Tube hydro-forming is the type of metal forming typically used in automotive applications, such as frame construction. Originally, tube forming was completed to create t-shaped joints for the oil industry. Tube forming is also performed on aluminum bicycle frames and other contoured frames for other equipment pieces. Both kinds of hydro-forming are used heavily in metal manufacturing today.