The forging process strengthens the metal by changing its grain structure to conform to the shape of the part, and thus yields a stronger final product than welding, casting and fabrication.
Aluminum forgings possess a smooth appearance, good fracture resistance, good thermal and electrical conductivity and are relatively economical compared to other commonly forged metals such as stainless steel, titanium and copper. Aluminum forgings come in a variety of shapes, such as rings, cylinders, bars, blocks, discs, sleeves, hubs, flanges, as well as any number of more complex custom shapes for particular applications.
Aluminum is about one third the density of steel, and is therefore preferred in many applications where weight is a prominent factor. Aluminum forgings are effective in work environments reaching up to 400 degrees Fahrenheit. Because of their low cost, low density, and excellent strength-to-weight ratio, aluminum forgings are used frequently by the automotive and aerospace industries, where decreased weight can contribute to greater efficiency. Aluminum forgings are also common components in tractors, ships, oil drilling equipment, engines, missiles and many other applications.
The aluminum forging process creates a sophisticated structure that improves the physical properties of the aluminum, enhancing its strength and mechanical properties while reducing its size. Most often aluminum forgings are created by heating a cast or extruded piece of aluminum and then using a large hammer or press that forces it to take the shape of a die.
Unlike in casting, the metal is never melted or poured; instead the forging process uses extreme pressure to form the metal into the desired shape. Hot forging is a very adaptable method, capable of forming all sizes and any sort of shape; it is also the only method for making larger aluminum parts, up to 25 tons. Cold forging is an alternate forging technique in which smaller quantities of aluminum ranging from room temperature to a few hundred degrees Fahrenheit are hammered or pressed into a die.
Cold forging creates an even stronger forged product by making slight alterations in the crystalline structure to line up with the shape of the part. The mechanical properties of aluminum make it one of the easiest metals to forge; that, combined with their economy and high reliability have given aluminum forgings a significant place in many modern industries.