IMAC-PRO was a technology project funded by the European Commission. Several European industrial partners and Universities worked together in the field of aerospace stiffener profiles made of fibre reinforced plastics (CFRP). Main focus was a high volume production to realise the increasing demand for future aircraft parts. The developed technologies should also offer a high potential for cost effective production.
The technological objective of IMAC-PRO was the development of a complete integrated process chain for the cost effective serial production of optimised CFRP stiffener profiles (e.g. frames, stringer, struts, floor beams, drive shafts) for all kinds of aircrafts (passenger planes, helicopters, fighters) based on textile technologies in combination with advanced injection and curing technologies.
Profiles are one of the most important structural components in aerospace as well as for many applications in ground transport, marine and mechanical engineering. Together with the skin they form lightweight structures with high stiffness and strength and additional functionality (for example aerodynamic shape). Various other profiles are used to build the inner structure of an aircraft fuselage. PAX floor cross beams and longitudinal beams, partly with integrated seat rails and the z-struts, used to support the floor grid, can be mentioned as representatives of profiles which are necessary in a very high quantity.
Therefore, the optimised design and cost effective manufacturing of profiles is of very high interest, which will significantly grow in the future due to the rapidly growing aircraft market and the demand for lightweight designs to improve the ecological compatibility of planes and helicopters with respect to a reduction of aircraft production and development costs.
The project consists of a management work package and six technically oriented work packages. The project structure derives from technical aspects and summarises common tasks like the development of preforming, high volume production, curing and testing. The order of the work packages is mainly chronological, because most of the development steps need input from previous tasks.
The project addressed different types of aircraft stiffener profiles. The common characteristic of these parts was a very huge length in comparison to dimensions of the cross section. They can be divided into two main categories due to the significant impact on the manufacturing technology necessary for the production:
- Massive profiles like floor beams and frames with edge dimensions in the range of 50 to 400 mm and wall thicknesses from 0.5 to 8 mm. These profile types have the additional challenge that their cross section shape and their wall thicknesses may change along the profile continuously or periodically;
- Stringer profiles with relative small cross section dimensions in the range of 50 mm, no changing of the cross section, but partly single or double curved and of even greater length up to 30m.
For the profile type 1, the braiding technology was the baseline for preform production. Profile type 2 were addressed with hot pressing and the Fibre Patch Preforming (FPP). The development of the preform technologies were merged in the WP3 'Development of preform technologies'.
The composition of almost all major WPs follows the same logic. The WPs always cover the two main categories of profiles, but they distinguish in detail between the technologies for their production.
The IMAC-PRO project has developed an integrated process chain for cost effective serial production of optimised fibre reinforced plastic stiffener profiles like frames and struts. These stiffener profiles can be used in all kinds of aircrafts: planes, helicopters, fighter planes. The profiles are based on textile technologies combined with advanced injection and curing technologies.
Development of novel profiles that are lightweight, and have a high stiffness and strength.
Stiffness profiles are one of the most important structural components. Not only in aerospace but also in ground transport, marine, mechanical engineering, etc.
Profiles combined with the vehicle's skin, form lightweight structures that have high stiffness and strength. Design optimisation and cost effective manufacturing of profiles is therefore of very high interest, due to the rapidly growing market and demand for lightweight designs with high stiffness and strength.
Innovating for the future (technology and behaviour): Promoting more sustainable development