Obiettivo
Hill's non-quadratic yield criterion was found to work much better for aluminium sheet than the quadratic criterion originally developed for sheet steel. Reliable procedures for the determination of parameters for the new criterion from bulge test data were developed.
Enhancements to the FEM simulation program included:
A new material model for aluminium based on Hill's non-quadratic yield criterion
A hyperelastic material model for rubber (Mooney Rivlin)
A module to simulate pressure build-up in enclosed volumes
A new material model for superplastic materials
A regulation scheme to calculate pressure cycles for specified maximum strain rates during superplastic forming.
With the enhanced FEM code it was possible to accurately simulate thickness distributions, tearing, wrinkling and springback during deep-drawing, rubber-pad, fluid-cell, superplastic and stretch forming of aluminium sheets.
Techno-economic evaluation software was developed for respectively short, medium and long-term planning.
The alternative forming processes investigated in the project such as rubber pad and superplastic forming did offer technical advantages for certain parts which were difficult to form. However techno-economic studies showed that these processes could not compete with conventional deep drawing at the high production rates which occur in automotive mass manufacture, so that they would only be of interest for niche vehicles and/or prototyping.
The goal of the proposed research is to enable European automotive and aerospace industry to identify, for a given part to be manufactured from sheet aluminium, the most economical and technically effective manufacturing process, taking into account the type of production, volume of production, costs, etc....
To achieve this the project will investigate the practical production of typical parts taken from the car and aerospace industry in a variety of aluminium sheet forming processes and evaluate the results through techno-economical studies including information flow considerations and production plant designs.
In parallel the Finite Element Method (FEM) and Computer Integrated Manufacturing techniques will be developed to provide validated software tools for use by the industrial partners with the parts to be examined in this project. At the end of the proposed research, the software tools will enable the industrial partners to perform the techno-economical studies for a new aluminium sheet part fabrication on the computer taking into account the production variables. The proposed research will lead to improvements in current manufacturing and design techniques for the fabrication of sheet aluminium parts. It is anticipated that this will lead to a 50% reduction of design to product time and enable the manufacturing industry to more effectively introduce appropriate design and fabrication technologies for the production of sheet aluminium parts.
It is considered that the technology exchange between the various industrial partners offered by this project will be of great mutual benefit. This in turn will lead to improved industrialization of these materials and greater competitiveness for a wide range of European industries.
Campo scientifico
Invito a presentare proposte
Data not availableMeccanismo di finanziamento
CSC - Cost-sharing contractsCoordinatore
65760 Eschborn
Germania