Two forging techniques that are somewhat similar can have vastly different applications and associated costs. For example, the dies used in closed-die forging are custom designed and capable of creating more complex parts than in open-die forging. This is challenging for manufacturers since any issue with a traditional die prototype requires engineers and designers to identify the problem and adjust the specifications using actual physical materials.
Despite these challenges, many manufacturers that use closed-die forging have yet to integrate simulation software into their workflows. Simulation software substantially reduces the risk of using customized dies to forge complicated shapes by anticipating failures and defects before they occur.
Let’s review the advantages and disadvantages of closed-die forging and explore how simulation software can help.
Closed die forging is a metal forming process in which a heated metal billet is placed between two dies that contain a pre-shaped cavity. When high pressure is applied, the metal flows into the die impression, taking the exact shape of the cavity.
This process is also known as impression-die forging, because the final part is formed according to the impression engraved in the dies.
Unlike open die forging, where the material is compressed between flat or simple dies, closed die forging uses precision-shaped tooling to produce complex geometries with tight tolerances and consistent mechanical properties.
The closed die forging process follows a series of controlled steps designed to ensure precise metal flow, dimensional accuracy, and optimal mechanical performance.
Although the exact parameters vary depending on material and part geometry, the process typically includes the following stages:
A metal billet or preform is heated to a specific forging temperature. Proper temperature control is critical, as it directly influences material ductility, grain flow, and final mechanical properties.
The heated billet is placed into the lower die, which contains a pre-machined cavity corresponding to the desired part shape. Correct positioning ensures uniform material distribution during deformation.
A forging press or hammer applies compressive force, causing the material to plastically deform and flow into the die cavity.
At this stage, metal flow behavior becomes highly complex and depends on:
Controlling these parameters is essential to avoid defects such as laps, underfilling, excessive flash, or internal stresses.
Excess material flows into narrow gaps between the dies, forming what is known as flash. This flash is later removed in a trimming operation.
The forged part is cooled under controlled conditions. Additional operations such as heat treatment, machining, or surface finishing may follow depending on performance requirements.
Because the closed die forging process involves complex thermo-mechanical interactions, predicting material flow, die wear, and potential defects can be challenging. Advanced numerical simulation tools are increasingly used to optimize die design, reduce trial-and-error iterations, and improve overall process efficiency.
Even before simulation software was available, closed-die forging was a popular technique because of its ability to produce parts with exceptional strength and toughness.
Part of the reason that closed-die forging results in improved mechanical properties is the high deformation rate as the original material is rapidly reshaped into the desired configuration. Closed-die forging is also a preferred production method for accommodating intricate designs with tight tolerances.
These significant advantages often outweigh the downsides of closed-die forging. Unlike simpler processes that can be put into production with minimal forethought, closed-die forging requires a substantial amount of planning and setup. The higher quality and value of the end product is often used to justify the initial expense.
Despite the various advantages and disadvantages of closed-die forging, simulation software streamlines the closed-die forging process by allowing teams to freely manipulate characteristics and specifications long before a physical prototype is ever made. Not only does this encourage innovation, but it also helps optimize the design of the die by testing a wide range of parameters without incurring additional expenses.
Instead of discovering mistakes while forging, simulation software alerts design teams to defects before production begins. From there, engineers can adjust the proposed specifications to reduce risk or redistribute stress to the die. The resulting changes may include substituting materials or modifying process parameters.
This continuous cycle of making improvements and responding proactively to potential points of failure increases efficiency and reduces the costs associated with rework in the real world. Between high tooling costs, overtime, and production delays, a physical die that doesn’t work properly can be extremely expensive for the company. A virtual die, on the other hand, costs nothing.
FORGE® continues to distinguish itself as an innovative, adaptive software solution with an easy-to-use interface for manufacturers integrating simulation software for the first time.
FORGE® allows design teams to set their own parameters and analyzes qualities such as deformation and flow according to those inputs. This encourages open experimentation and a natural process of discovery.
Many types of software perform well in metallurgical aspects or simulations but lack the comprehensive customer support, flexibility, and affordable price point of FORGE®.
Choosing the right software also depends on each manufacturer’s tolerances for dimensions, surface finishing, and other qualities.
By running various calculations and assessments on a digital prototype, FORGE® can check a part’s mechanical properties and determine whether designs comply with specifications such as SAE USCAR8. FORGE® also excels at anticipating issues like underfilling or flow-through defects.
Being able to anticipate outcomes challenges the traditional advantages and disadvantages of closed-die forging by eliminating key drawbacks. For instance, simulation software eliminates the high tooling costs of making multiple prototypes and takes the guesswork out of knowing when to transition to physical production.
Closed-die forging has remained a manufacturing staple for good reason. Simulation software amplifies its ability to produce customized and complex parts by mitigating many risks that can make closed-die forging an expensive technique.
With solutions like FORGE®, design teams can test process parameters and specifications in a controlled setting without making a physical prototype. If the resulting part doesn’t behave as expected, changes can be made without incurring new production costs or causing delays while another prototype is made. This freedom removes a substantial amount of mental pressure from the design process and gives engineers the flexibility to test new theories in a safe virtual environment.
Contact us to learn more about simulation software and the advantages and disadvantages of closed-die forging.