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What is Impression Die Forging?

what is impression die forging

Manufacturing processes are incredibly sophisticated, incorporating complex methods to produce the components and finished goods that many of us may take for granted. Impression die forging (also known as “closed die forging“) is one of many forging techniques, but it offers a wide range of applications and benefits.

Selecting the right process takes some understanding of each method plus its appropriate uses and advantages. Impression die forging is often one of the most complex, resulting in durable components with exceptional performance in many industries.

What Is Impression Die Forging?

As you may know, forging uses compressive forces to shape billet metal into more complex forms. In the case of impression die forging, two or more dies are used to shape a metal billet that’s been heated to the proper temperature. Depending on the component’s design, forging may require one set of dies or a multistage process with many sets of dies.

With multistage forging, a part can move through busting, blocking and finishing dies. The first two stages help form the part’s initial construction, while the finishing dies fine-tune geometrical details without significantly changing the item’s shape or increasing material flow.

How Does the Impression Die Forging Process Work?

Impression die forging, also known as closed die forging because each die set behaves a little like a pair of casting molds. This process uses a hammer along with the manufacturing dies, which are typically connected to an anvil. When the hammer is dropped on the workpiece, the hot metal flows and occupies the die’s cavities.

The hammer may only touch the workpiece for a few milliseconds at a time and may be rapidly dropped several times in a row.

Any leftover hot metal that’s pushed out of the die’s cavities is called “flash.” Since it cools down more quickly than the metal inside the die, it blocks more hot metal from escaping and turning into more flash. This also ensures that the remaining hot metal fills up the die. Once this forging process is complete, the flash is taken away and the finished product is left behind.

What Benefits Does This Forging Method Offer?

Closed die forging is very effective for shaping aluminum, steel, titanium, and a wide range of metal alloys. By enclosing the hot metal inside sets of dies, many kinds of three-dimensional shapes can be produced. This includes simple forms such as cubes, disks and spheres, but it can also be applied to multi-section parts that incorporate thin delicate webs and long, spindly shapes.

Impression die forging is also useful for parts with holes, pockets and protrusions, and even asymmetrical parts can be produced through this process.

Thanks to this forging process, high-quality components can be manufactured at a relatively reasonable cost. The resulting parts resist both fatigue and impact, are very durable and have higher strength-to-weight ratios. Sometimes, these parts are up to 20% stronger than those produced by other forging methods. Closed-die forging also generates less wasted metal, and this refined method is capable of higher production rates than other techniques.

Who Uses Impression Die Forging?

This forging technique is used in many manufacturing applications. You’ll commonly find closed die forged parts in the automotive industries as well as the railroad, mining, aircraft, aerospace and defense industries. Tool companies are also some of the most frequent users, thanks to the strength and reliability of impression die forged items.

Let Us Meet Your Manufacturing Needs

Closed impression die forging is just one of the many capabilities that Trenton Forging offers. With 3D printing and laser scanning, machining, die welding, machining, tooling and other processes, we deliver high-quality components to clients in many industries. We look forward to helping your company meet its needs, contact us today!

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