The virtualization of processes continues to grow and is applied broadly across numerous fields because it enables process optimization, improves efficiency and precision, and accelerates design modifications in an environment where rapid adaptation is critical. This technology has been successfully employed in sheet metal forming for over 25 years, using software specifically developed to simulate sheet metal behavior during stamping processes. These applications store simulation results and distribute critical data throughout the entire production chain.
Through consistent use of simulation software in sheet metal forming, achieving correlation rates of up to 80% between virtual and real-world outcomes has become relatively straightforward. The Pareto Diagram (Fig. 1) illustrates this correlation, highlighting how varying levels of engineering investment correspond to different degrees of alignment between simulated models and actual results.
Fig. 1: Pareto Diagram
Currently, achieving an 80% correlation requires only about 20% of engineering effort (Fig. 1). However, the significant challenge today lies in further increasing this correlation and continuously striving toward maximum predictive accuracy.
Essentially, this involves the ability to predict the future—a transformative concept offering significant benefits, though it remains challenging to implement fully.
Given that simulations guide real-world manufacturing, a primary challenge involves accurately executing in practice what was simulated virtually. Multiple parameters throughout the manufacturing process can fluctuate, causing discrepancies between simulation and the actual stamped parts.
Furthermore, quality standards are becoming increasingly stringent. Dimensional accuracy must be maintained within three-tenths of a millimeter, and surface imperfections on visible parts must be accurately predicted—often identified only through specialized lighting techniques. Maintaining dimensional tolerances in subassemblies and complete vehicle bodies (Body in White) while accounting for variations in individual components adds further complexity.
Therefore, even minor discrepancies between simulation and actual production parameters can significantly affect product specification compliance. In such cases, a detailed and methodical analysis of these parameter relationships is crucial. This involves comparing the mechanical properties outlined in raw material certificates (Fig. 2) against software-based material characterizations (Fig. 3). Manufacturing dates must also be considered, as these properties may vary over time.
Fig. 2: Example of a material certificate
Fig. 3: Example of a material characterization in the simulation
Another parameter affecting sheet metal flow is pressure distribution within the binder, resulting from the relationship between applied forces and contact areas. Therefore, comparing real-world pressure tables (Fig. 4) with virtual pressure tables (Fig. 5) becomes necessary.
Fig. 4: Example of a real pressure table at the moment of closing the sheet metal press
Fig. 5: Example of a pressure table in the simulation
Tribology also significantly influences sheet metal forming. Tooling surface roughness greatly impacts material flow and the quality of the final part’s surface. Thus, comparing simulation friction factors with actual tooling surface finishes (Fig. 6) is essential.
Fig. 6: Comparison between the friction factor used in AutoForm and the polishing used in practice on the tooling
The objective is to identify and understand any parameter misalignments between practical production and simulation to reduce discrepancies.
Overcoming these challenges requires a thorough and systematic verification process. Effective synchronization between virtual simulation parameters and real-world conditions ensures simulations reliably guide actual manufacturing processes, effectively creating a digital master.
The continuous pursuit of higher correlation enhances quality, improves efficiency, and reduces costs and lead times, meeting growing market demands.
Therefore, it is essential to break traditional paradigms, such as fully trusting simulations to accurately guide production. Achieving this demands smooth information flow between departments, allowing simulation results from one area to serve as valuable inputs for another.
Ensuring seamless information flow necessitates adopting a holistic global perspective, from initial product feasibility analysis through to production line execution. This perspective encourages a collaborative approach, with departments and process stages recognizing themselves as partners working toward a shared goal. Such collaboration fosters an organic and barrier-free information exchange.
The flow of digital information is essential not only for departmental integration but also for connecting the broader supply chain. Effective data sharing improves the detail and accuracy of information throughout the production process chain (Fig. 7).
Fig. 7: Information flow
In summary, excellence in forming and assembling sheet metal components, while meeting market demands for cost, quality, and delivery timelines, relies on fully integrating digitalization and simulation across all processes. Aligning critical parameters and maintaining smooth digital information flow is key. Only through such integration can virtual predictions reliably translate into real-world successes, delivering consistently accurate and reliable results.
