FEM Services

We are specialized in the simulation of highly non-linear and dynamic short-term processes such as sheet forming and impacts for crash, passenger and pedestrian protection scenarios.

In our simulations, we focus on the realistic representation of material behaviour. Therefore, the characterisation of material data usually complements our simulations projects.

For every project, we determine the simulation method that suits the task at hand best. We consider which programs you use to make sure that solutions can later be applied at your company.

Simulation methods

A good mesh, a good material model and a good material card are prerequisites for a predictive simulation, but usually, the model must also be preprocessed to include local properties:

Most materials are not isotropic, so the primary direction of anisotropy must be determined.

Finally, the production process of a part causes local differences of the material behaviour. Accounting for those differences can improve the accuracy of the simulation. Information on the local distribution can be taken from experiments or, more commonly, from process simulations.

Some examples for locally different behaviour are:

Application: Sheet metals

Rolled metal sheets are very common in body-in-white assemblies. MF GenYld + CrachFEM can asses the validity of the deep-drawing process and the behaviour in crash and safety load cases.

Various yield loci

An accurate prediction of the sheet deformation is indispensable for forming simulations and is a prerequisite for failure assessment. MF GenYld offers a large variety of orthotropic yield loci. It can also model anisotropic hardening under compression, shear and equibiaxial loads, non-associated flow and the Bauschinger effect via isotropic-kinematic hardening.

Non-linear strain paths

Strain paths in realistic load cases are rarely linear. The failure assessment of CrachFEM can account for non-linear strain paths with a tensorial accu­mu­lation of the fracture risk and with an accurate representation of the strain history in the submodel for instability prediction.

Local properties

When assessing stamped parts in crash loads, the manufacturing history of the part should be considered to account for local effects. This comprises at least the deformation history from the deep-drawing simu­la­tion, but can also include hardness distribution from quenching or press hardening, heat-affected zones of weldings and stress concentrations near holes and rivets.

Application: Short-fibre reinforced polymers

Thermoplastics with short glass fibres are used in the front end and interior of cars and other vehicles. They play a significant role in assessing occupant and pedestrian safety.


The short fibres align themselves during the mould-injection process. Where the fibres are aligned in the same direction, the local behaviour is orthotropic. In regions where the fibres have no predominant alignment the local behaviour is isotropic. The hardening and fracture characteristics in these zones is markedly different.

Therefore, the local distribution of fibres should be carried over from injection simulations so that the behaviour can be interpolated according to the degree of anisotropy.

Mechanical properties

The elasto-plastic behaviour varies not only locally according to the fibre distribution and with the load angle, but also with the stress state. MF GenYld can model this with anisotropic hardening. The elastic behaviour is dependent on the local fibre direction and on the strain rate.

A special model for anisotropic fracture can take into account the strong direction dependence of ductile fracture in regions of high degrees of anisotropy.

In addition, endless fibre-reinforced thermoplastics can also fail under brittle fracture, which CrachFEM can assess with a stress-based criterion.

A suite of modelling tools

MATFEM can help you to incorporate such effects into your simulation models. Our material model CrachFEM uses the lock-and-key principle to turn the process data into a local distribution of material behaviour.