Sheet Metal Stamping Simulation

There are TWO ways to get "accurate" results that will match reality as closely as possible:

StampingSimulation.com was recently published in the February edition of MetalForming Magazine. For those who missed it, you can check out the article here.

For a long time now, I have been sounding like a broken record about how important it is to test steel samples for use in simulation, and how “generic” properties or “mill certs” are hardly worth the paper they are written on. Also, I am always strongly suggesting that our customer do not “guess” material properties for use in simulation, and if they do, they must assume responsibility if reality does not match simulation.

In the current edition, there is an excellent article written by Art Hendrick. It's a good insight in to how in fact, Simulation is indeed always perfect, but the material properties that clients provide/enter are not always accurate - and that is where the problems can start. Here is what Art says:

The simulation is perfect: Based on the data entered in to the computer and the mathematical data that the computer is using, the results will be accurate. COmputers don't make mistakes.

The problem is insufficient data. Very simply, the computer is not perfectly replicating what might actually be happening in the die and press.

This is a video of typical draw tool with a lower cushion. The pressure for the binder is supplied by the press machine's hydraulic cushion, instead of using nitrogen gas springs.

This is typical for larger parts when more than 100 tons of binder pressure is needed. It also allows the binder pressure to be adjusted up or down easily, for best results during tryout.

The client had designed and fabricated a tool for a new automotive project. During initial tryout, the process formed the part successfully. HOWEVER, once the tool was set for production, constant SPLITS resulted.

Initially, a simulation of the current process was performed, to determine if the splits were expected. The simulation result shows that indeed, the material is predicted to split. This is due to excessive thinning in the current process.

How does StampingSimulation.com accurately simulate your specific material? The uniaxial tensile test is performed to collect data from actual steel samples, and the results are used in simulation to accurately model the hardening behavior of the steel being simulated.

Incremental sheet metal forming simulation not only predicts common defects such as wrinkles, splits or springback but is also regularly used to accurately calculate blank shape and trim developments.

Welcome to 2009! It's a new year so let's talk about something that might be new to even those who have seen and used simulation many times previously. The Forming Limit Diagram (FLD) is the fundamental tool which is used to judge whether a formed sheet metal part is predicted to fail or pass, when analyzing simulation results. The "standard" FLD assumes a linear strain path, however, strain paths are not always linear in reality.

StampingSimulation.com’s Pay As You Go simulation services allow any tooling company of any size to benefit from world class AutoForm sheet metal forming simulation software and even the seemingly simple parts benefit too.

StampingSimulation.com’s Pay As You Go simulation services allow any tooling company of any size to benefit from world class AutoForm sheet metal forming simulation software. Williams Tooling, Dorr MI, is a regular client who use StampingSimulation.com’s SimulateLite service to simulate their solid tool designs prior to commencing tooling fabrication.

Sheet metal forming simulation has proven to be accurate time after time. Why then, does the industry hesitate to simulate upfront and save time and money on the shop floor at the end of the project? Those who do reap the rewards.

AutoForm-Incremental simulation technology includes the ability to design, develop and simulate both sheet hydroforming and tube hydroforming problems, including tube bending and forming (crushing). StampingSimulation.com now offers this functionality as part of their existing simulation service products, SimulateLite (Virtual Tryout) and SimulateComplete (Process Development).

When using a tool like AutoForm to design die faces, with the intent of simulating the design for verification, there is a basic path or set of steps that are used to end up with a die face design. We will nowbriefly out line such steps.

The best way to answer this question is via the Forming Limit Diagram (FLD). The colors and predictions of splits/compression, etc., are all based on the the FLD