REsearch on ThermoPlastic repAIRs

The future of aeronautic factories is oriented to manufacture lighter and cost-effective components using greener materials like thermoplastic composites (TPCs).

In this sense, given their increasing use, providing with cost-efficient repair methods for their complete integration in production is needed.The main objective of RETPAIR is the development of new high performance, flexible and cost-effective, automated and robotized net-shape technologies to rework and repair TPC parts to be integrated in the manufacturing line.

The proposed solutions assure one-side accessibility and are supported by a digital-based methodology to assist the patch design and manufacturing.

An induction welding solution for structural damages repair based on pre-manufactured patches will be developed, and two in-situ consolidation solutions for structural and non-structural applications based on automated and robotized layer-by-layer patch in-situ creation: an automated laying (AL) solution based on ATL/AFP technologies (automated tape laying/automated fibre placement) will be investigated for structural and large size repairs, and a 3D printing FFF-based (Fused Filament Fabrication) solution, using both continuous carbon fibre filaments and short fibre filaments will allow to tune patches’ strength for different repair requirements (structural and cosmetic)To assure the thermal and mechanical quality of the repair, the critical process parameters (temperature, pressure, times/rates) will be monitored and controlled.

The applicability of the new repair technologies for different damage scenarios (Single Part Level, on Major Component Assembly Level, Final Assembly Line) will be investigated, and the required work of a future industrial implementation for the technologies towards TRL6 will be analyzedRETPAIR developments will result in flexible and accurate repair technologies for high performance and quality solutions, thus collaborating in TPCs growing use in the aeronautic industry