Thermal Cycling Durability of Bonded PZT Transducers Used for the SHM of Reusable Launch Vehicles

Loïc Mastromatteo (1) , Ludovic Gaverina (1) , Florian Lavelle (2) , Jean-Michel Roche (1) , François-Xavier Irisarri (1)

1 DMAS, ONERA, Université Paris Saclay [Châtillon]
2 CNES - Centre National d’Études Spatiales [Paris]

In the context of recent reusable launch vehicles (RLV) developments, the SHM methods could be useful to help fast and economic revalidation of RLVs between launches, provided that the SHM transducers keep their functionality under extreme environmental conditions during flight. This paper focuses on the thermal cycling durability of PZT piezoelectric transducers bonded on a Carbon Fiber Reinforce Polymer (CFRP) composite plate. The temperature cycles are set to be representative of the thermal loadings that the structure of a launcher could experience under a thermal barrier: limited number of cycles (<10) of short duration (<10 min) and high temperatures for thermoset-matrix composites (150 ∘ C). The heating is generated using a CO2 laser in order to obtain the steep thermal ramps (60 ∘ C/min) and gradients through the plate thickness to best reproduce flight conditions. To our knowledge, very few research studies have been carried out so far on the resistance of SHM systems under such environment. The degradation of the system formed by the composite plate, the adhesive and the PZT transducer is studied, in comparison with the state of reference before cycling, with three different approaches. First, electromechanical impedance is measured during the entire thermal cycling. Then the functionality of a guided wave SHM system is evaluated based on the emission and reception of Lamb waves between PZTs attached to the surface of the plate. Finally, Laser vibrometry is used to provide a mapping of the emitted Lamb waves propagation and to identify possible debondings or changes of amplitudes of waveforms after the thermal cycles.

Mots clés: Electro-mechanical impedance (EMI); Guided waves (GW); Laser Doppler Vibrometry (LDV); Reusable launch vehicle (RLV); Durability; Carbon Fiber Reinforce Polymer (CFRP); Composite

Domaines: Sciences de l'ingénieur [physics]; Physique [physics]; Chimie

Loïc Mastromatteo, Ludovic Gaverina, Florian Lavelle, Jean-Michel Roche, François-Xavier Irisarri. Thermal Cycling Durability of Bonded PZT Transducers Used for the SHM of Reusable Launch Vehicles. European Workshop on Structural Health Monitoring. EWSHM 2022 - Volume 2, 254, Springer International Publishing, pp.727-736, 2023, Lecture Notes in Civil Engineering, 978-3-031-07257-4. ⟨10.1007/978-3-031-07258-1_73⟩. ⟨hal-03772283⟩