Closed Die Forging

Sometimes referred to as impression die forging, closed die forging is a manufacturing process through which precision parts can be produced from a wide range of metals and alloys. Non-ferrous alloys like brasses and bronzes are the most common materials; but aluminum alloy, carbon steel, stainless steel, and alloy steels can also be worked through this process. 

Closed die forgings can be produced in essentially any 3D shape, including complex part designs. And while the process is most often used to produce smaller, high tolerance parts, impression die forging can be used to create parts weighing thousands of pounds.

What is Closed Die Forging?

Closed die forging is a form of drop forging; that is, a process where a hammer is “dropped” onto the workpiece to deform the material into the shape of the die, or mold. In most cases, the hammer is not actually dropped but rather moved into place mechanically.

In closed die forging, the bottom half of the die (mold) is held in place on the bottom table or anvil of the forging press. The top part of the steel die mold is held in place on the ram. When put together, the interior cavity of these dies creates the shape of the part being forged. Metal or alloy material (billet) is heated just past the point of plastic deformation and placed on the lower die. The hammer, or ram, is activated and the top die strikes the bottom die, which fills the contours of both dies, molding the metal into the forged part.

A forging press, often just called a press, is used for closed die forging. There are two main types of presses: mechanical and hydraulic. Mechanical presses function by using cams, cranks, and/or toggles to produce a reproducible stroke with a preset amount of force.

In some cases, when forging steel or stainless steel, the ram die may impact the bottom die several times to ensure all of the contours are filled. When working with most copper and aluminum alloys, a single impact is all that is needed. Preformed billets may be required for some closed die forging applications.

Due to the high amounts of pressure placed on the workpiece, it is common for small quantities of metal called “flash,” to flow out between the die halves. Flash cools relatively quickly and therefore helps block or reduce further flow between the dies. Flash is trimmed off once forging is complete.

Why Choose Closed Die Forging?

  • Hot forging prevents work hardening associated with cold forming
  • Large parts can be produced with high precision using closed die forging
  • Closed die forging can produce near net shapes, and, in some cases, blind cores that require only a small amount of machining or finishing
  • Closed die forging is a cost-effective process for large production runs
  • Forging provides superior mechanical properties over casting, due to the internal grain structure formed in forged parts

Full-Service Closed Die Forging from Deeco Metals

Deeco Metals can supply the custom closed die forgings you need. We work with copper and copper alloys (brasses and bronzes), aluminum alloys, all types of steel, stainless steels, and nickel alloys. Our impression die forging capabilities enable us to produce high precision parts that match your design specifications. Our team will work with you, as needed, to optimize your designs for more efficient and economical production, without sacrificing the fit, form, or function of your parts.

We provide a range of post-forging secondary service to add further value to your forged parts. We offer machining, surface finishing, plating, and more, to give you more complete parts that require less additional processing on your end. We are a single-source provider for complete closed die forgings.

Contact Us for Precision Closed Die Forging

We are your #1 source for custom, close die forged metal parts. Contact Deeco Metals to discuss your project or to request a quote.