Advanced Simulation and control of tribology in metal forming Processes for the North-West European Consumer goods and Transport sectors (ASPECT)

WP leader: ESI GROUP

Partners involved:

M2i; Triboform; ESI; Falex; UT; Z&G; Tata Steel; inspire; Opel; Philips; FILZEK.

Description of work: A micro-mechanics-based friction model will be developed by UT with support from Triboform, to predict the local friction conditions between the lubricated work piece and forming tool at elevated temperatures. The extended friction model will be calibrated with relevant experiments (Falex and FILZEK - lab scale; Tata Steel - component scale). Z&G will provide input on lubricant properties and will actively take part in the experimental plan led by Tata Steel with the contribution of Falex and FILZEK. The metamodels resulted will be applied in two Finite Element simulation packages: PAM-STAMP (by Triboform and ESI, assisted by Opel) and MARC (by M2i, assisted by Philips) allowing thermo-mechanical coupled deep drawing simulations. A balance between computational efficiency and accuracy will be sought after (ESI, M2i). A metamodel for the machine settings will also be developed by inspire, based on a number of thermo-mechanical coupled FE simulations, to allow the adjustment of the machinery settings.

The output of this Work Package will consist of four technologies:

1. Friction model including the effect of transient temperatures, validated at lab (TRL 5) and pre-industrial (TRL 6) scales;
2. Built-in capability in a software (TriboForm) to calculate friction based on temperature inputs; 3. Sheet metal forming simulation code;
3. Computationally-efficient algorithm to simulate the transient temperature effect, to be eventually embedded in two commercial software codes (PAM-STAMP and MARC).

Cooperation in North-West Europe:

The temperature-dependent material properties will provide the data for further integration of temperature dependence into the Triboform software. While the software has a built-in capability to deal with variable tribological conditions, the temperature effects were hitherto not dealt with, and these represent the main innovative step of the ASPECT project. The output requires a strong collaboration between the research organizations and the participating SMEs. The "experimentalists" (Falex, FILZEK), will work closely with the "modellers" (Triboform) to develop and validate a tribological model able to capture the variation of friction with temperature during forming. The model will be further implemented in industrial codes and validated at component (pre-industrial) level. The material producers (Tata Steel, Z&G) and the end-users (Opel, Philips) will contribute their knowledge on materials and forming processes, respectively.

WP leader: inspire AG

Partners involved:

M2i; Triboform; ESI; UT; Tata Steel; Opel; Philips; FILZEK.

Description of work:

The numerical tools developed will be used to determine optimal process parameters, not only for the steady state, but also for the transient part of the process to account for the temperature effect on part quality. An adaptive control strategy will adjust the process parameters within the optimal predicted range. This will be done by linking measurements of the local temperatures during the transient process with the actuators. For instance, the system should be able to automatically adapt the required blankholder force, based on the temperatures measured with sensors in the tool. This adaptation needs to be done in real time, using a metamodel derived from the earlier simulations. By doing so, the effect of temperature during start-up is suppressed, directly enabling stable and zero failure production.

A sensor technique will be developed by inspire to measure all relevant parameters influencing the forming process. An adaptive control system will be designed using a priori knowledge from numerical simulations and in-line measured data to adjust the process to the instantaneous conditions (inspire). Finally, the sensor technique and control system will be integrated in the stamping line (inspire, Opel, Philips), where the working principle will be validated during the transient part of the process at industrially-relevant level (TRL 6-7 at Opel and Philips). Tata Steel will provide expert knowledge of material behaviour. UT, Triboform, FILZEK, ESI and M2i will be involved with a consultative role in the definition of the tool control strategy.

The output of this Work Package will be a tool control system that will enable the adjustment of the process conditions based on temperature-dependent friction inputs.

Cooperation in North West Europe:

inspire AG from Switzerland, the European leader in control technology, will cooperate with the Dutch and German partners in the development of a robust and efficient control system. Opel and Philips will contribute on connecting the data acquisition hardware to the stamping line. The system will use the machine settings of the stamping line, thereby requiring less additional hardware, and making it easy to use by the machine operators. Internal training will take place at Opel and Philips on the implementation of the control system. The success of the control system will be documented by means of a report and video, made available on this website. The public demonstrator facility at FILZEK will disseminate the results via invited lectures from inspire.

WP leader: ESI GROUP

Partners involved:

M2i; Triboform; ESI; Falex; UT; Z&G; Tata Steel; inspire; Opel; Philips; FILZEK.

Description of work: The numerically predicted temperatures and the process windows for sheet forming processes based on these temperatures will be used for the evaluation of the correct parameter settings for industrial sheet forming processes. The demonstration of the model-based control will take place for two sheet metal forming processes (deep drawing) in which the temperature plays an important role on the friction effects and on the process performance during stamping:

1. Forming process for Automotive car parts, at Opel;
2. Forming process representative for small components in Consumer products, at Philips.

 The output of this Work Package is a holistic approach of virtual design and real-time control system

Demonstrated for two reference cases at industrially-relevant level

Cooperation in North-West Europe:

Opel and Philips will implement and run the demonstrators; inspire will connect the sensors to the unit for signal process and to the press control. The main research partners (UT, M2i and Triboform) and ESI will participate as observers, to get insights on iterative improvement of the tribological model. Falex and FILZEK will be involved in the preliminary validation steps on the demonstrator lines. Tata Steel and Z&G will contribute knowledge on materials.

The knowledge will be brought in the operation of the public demonstrator at FILZEK (WP LTE - Long term effects), which is a long-term activity meant for the education and training of the tribological and forming engineering community in the EU.