The first period of NEODAMP project is developed between M1 and M18. During this period, the requirements were fixed, and the test plan for the characterization/validation of the vibration damping composite material was defined. One of the most important and challenging task was successfully accomplished: the acoustic material modification. The preliminary characterization tests of the new damping material were also performed. However, there was reported a delay in the manufacturing of the coupons for the tests, since the concerned material was not ready at the time planned. The reason behind this delay is that there were many challenges for Hexcel to obtain the desired new damping material due to the complexity inherent to the re-formulation/manufacturing process, although these were overtaken.
The second (and last) period of NEODAMP project (M19-M36) have been successfully completed. During this period, the modified hybrid material was used to manufacture coupons for the final test plan. The tests were conducted and analysed, although their results were reported to be unsatisfactory from the structural point of view. Due to this fact, an assessment on alternative laminate configuration, architecture, and elastomer formulation was conducted at this stage. After that, a new material architecture was determined as a compromise solution between acoustic and structural performance. Finally a demonstrator was produced by means of automated tape laying (ATL) considering the selected architecture; the demonstrator is comprised by a flat plate with two omega stiffeners.
The final conclusions of NEODAMP project are positive; a multifunctional material that enhances the acoustic performance of a standard CFRP, without detrimental effect to its structural properties, has been developed. The performance still needs to be improved in order to be suitable for the fuselage application, since the last architecture does not fulfil the acoustic performance at the 20% of the defined temperature range. However, the material is suitable for many other applications, and implies an important reduction of cost, weight and enhanced automation with respect to the current State of the Art.
With regard to the dissemination of the NEODAMP activities and results, in the first place the demonstrator has been exhibited at the JEC World event in Paris. Secondly, the technical details of the project have presented at the EMuS 2019 (European Conference on Multifunctional Structures) in Barcelona, a technical paper can be found at the conference proceedings.
