The first main goal achieved was the development of structural repair solution based on hard-patch welding. A new concept based on co-consolidation strategy was developed, using a flexible induction blanket to heat the part and consolidate the patch directly on the damage to be repaired. Consolidating the plies to create the patch at the same time that the joint to the part to be repaired is created, doing both activities at the same time, since temperatures above melting temperatures are achieved through all the plies and on the interface with the damaged part.
Other of the main challenge covered by RETPAIR was developed an automated FFF-based solution for in-situ repair patch manufacturing for small-medium size repairs, and AFP based solution for big repairs. Appling an automated manufacturing strategy to build the repair directly above the damage, using a ply-by ply an approach in situ repair in both scenarios. Both technologies were proved and a processes windows were studied in both cases to determine the optimum process parameters to be used for a further mechanical test campaign, that feed Finite Element Models to assess repair process.
To define the specific requirements for in-production-repair, establishing the repair applications scenarios for setting the study cases. Based on this, a screening was carried out in order to select the technology for hard patch and for in-situ repair patch application to be investigated in WP3. In addition to which, it was carried out a selection and study cases design for the different repair scenarios.
Through this period, it was also developed the digital based patch repair design methodology. For this, it was required to design the data acquisition, point cloud generation and CAD model building, after that it was needed to develop the patch design based on the digitalised damage. AIMEN provided the input for CT activities, which was scanned damaged surfaces (point clouds). CT has developed a set of automatizations that allows the recognition of the type of damaged, and the generation of the 3D models and Ply-by-Ply models of the repair patch manufactured.
Repair solutions were validated determining the mechanical performances and thermal properties for the different study cases. For each repair technology the process window was study and optimum process conditions were defined. Defining set up configuration that allows to carry out repairs on a scarf stepped surface to be repaired, as it is needed in RETPAIR project. All the technologies were validated at a representative level, and 3D environment simulations were studied on the Multi-Functional Fuselage Demonstrator to determine its reparability with RETPAIR technologies. Furthermore, a road map until TRL 6 was defined to scale up the technologies to a industrialization level.
During the second period of the project, several interventions have been carried out in conferences and fairs to disseminate the results.
Oral Presentations: - ECCM20. - 12TH EASN; - 13TH EASN
Poster on congress: MFFD Stakeholder Event 2023.
Participation on workshops: - Recycling in Aviation. Clean Aviation Workshop; - 13TH EASN
Fairs: - ITHEC22; - JEC WORLD. 2022 and 2023
Scientific publications: - ECCM20. 20th ; ICCM2023
A dedicated project website was created for the RETPAIR project (
http://www.retpairproject.eu/(se abrirá en una nueva ventana)).