Descripción del proyecto
Una nueva técnica de unión híbrida mejora las propiedades mecánicas y químicas de las juntas
La unión de los grandes subcomponentes de las aeronaves puede suponer un reto tanto por el proceso de unión en sí como por su efecto a largo plazo en la integridad de la aeronave. La soldadura por puntos por agitación y fricción es una prometedora técnica de unión en estado sólido que utiliza la fricción para precalentar y ablandar un componente, tras lo cual se le da forma para producir una unión. El proceso puede reducir el peso al eliminar elementos de fijación como los remaches y también puede unir materiales distintos. El equipo del proyecto DAHLIAS, financiado con fondos europeos, optimiza esta prometedora técnica y la combina con la aplicación de un sellador con propiedades adhesivas. El sellador no solo protegerá la junta contra la corrosión, sino que también reforzará su rendimiento mecánico.
Objetivo
The main objective of the DAHLIAS project is to optimise hybrid joining (Refill Friction Stir Spot Welding, RFSSW, with an adhesive sealant bond) for application in aircraft structures. RFSSW is a solid-state joining technology especially applicable to lightweight alloys in similar and dissimilar configurations. The process has been successfully applied to difficult-to-weld and non-weldable alloys and is considered a potential replacement of mechanical fastening. Overlap joints in aircraft structures require the use of sealants for corrosion protection reasons. Using sealants with an adhesive function would complement the high quality joints produced by RFSSW by not only protecting against corrosion but also contributing to the overall mechanical performance of the structure. To achieve the main goal of this project a work plan consisting of eight work packages has been devised. Two work packages are focused on the RFSSW process development using standard samples with and without adhesive sealant. In parallel the adhesive sealant technology, including surface pre-treatment will be developed. The hybrid joining solution developed in this project will be compared to conventional joining technologies to define its potential. Hybrid joining brings a number of advantages to production and performance of aircraft structures. The change from differential to integral design introduces new challenges in the analysis of mechanical performance. Hence, the damage tolerance behaviour of hybrid joints is also investigated in this project. Quality control methods will be investigated by selecting NDT methods and by process control based on online monitoring of parameters. In the last phase of this project technology demonstrators will be produced to evaluate the capabilities of the proposed technology in actual aircraft structures. The consortium (3 R&D and 2 industrial partners) has the exact fitting, prooven expertise and high excellence. HZG (coordinator) holds key patents.
Ámbito científico
Programa(s)
Régimen de financiación
CS2-IA - Innovation actionCoordinador
21502 Geesthacht
Alemania