For addressing the need to design components with better performance, we offer specific tests to better describe sheet formability at room and high temperature an reproduce part performance in FE codes, coupling micromechanical characterisation with macroscopic tests.
NOVEL METAL CHARACTERISATION SERVICES
Part and forming process design
- Forming limits evaluation at room and high temperature
- Edge cracking modelling and prediction
- Modelling of part performance
- Modelling of H embrittlement
- Material data for modelling
Forming limits evaluation at room and high temperature
High temperature FLC characterisation
Frictionless determination of sheet metal forming limit behaviour under tempereatures up to 900ºC. These measurements are highly interesting for hot stamping processes of aluminium and steels sheets.
Biaxial tensile test at room temperature
Biaxial tensile tests using optimised cruciform speciments permit the measurement of linear and non-linear strain paths at room temperature, at quasi-static conditions or at high deformation rates. The straith path can be controlled by the displacement of the machine, using DIC system with 3D calibration.
Deep drawing test
This test allows to predict the critical points in real stamping components and can be used for the optimisation of deisgned die, fast acceptance inspection for new sheet/coil, FEM verification and providing a complex view of formability (relation between stress and strain state).
Edge cracking
Edge cracking modelling and prediction
Simulation by FEM of sheet forming operation to accurately predict edge cracking failures. A methodology has been defined to apply the ductile damage model implemented in the commercial software ABAQUS on the edge cracking prediction. An energy-based failure criterion based on the EWF tests is implemented in the model.
Modelling of part performance
Modelling of part performance (crashworthiness)
Modelling of crash boxes in terms of absorbed energy, plastic strain distribution and crack formation and propagation. The simulation is performed using the ABAQUS software. The calibrated energy-based failure criterion based on the EWF tests is implemented in the model.
H embrittlement
Modelling of H embrittlement
Coupled diffusion-structural FEM able to estimate the hydrogen concentration distribution into structural components of AHSS. This model considers the principal factors influencing the hydrogen migration in stressed components and it is implemented in the commercial FE software Ansys Mechanical for its use in industrial applications.
Material data for modelling
Smart material data characterisation
A user-friendly interface module to calibrate experimental data to material and fracture models in FE-codes. Routines can be established to link the process the customer wants to analyse (forming, crash, etc.) to needed experiments in order to deliver a calibrated and proper material model implemented in the customer’s FE-code.
Post necking behaviour and fracture strain for anisotropic behaviour
Characterisation of post necking behaviour and fracture strain for anisotropic sheet metals using the stepwise modelling method (SMM). This is a direct method to characterise the post necking plasticity for sheet metals, which is based on full field strain data obtained by tensile testing.
Fracture strain measurements
Improved fracture criteria for sheet metal forming and failure simulation (edge cracking, etc.). The method is based on the measurement of local fracture strains on the fracture surface of notched and pre-cracked specimens.