Electro-thermal functional fatigue properties of deicing composite laminates: Internal thermal and compression cycle tests

Deicing composite laminates often undergo functional and structural fatigue during long-term electro-thermal deicing process, posing a potential threat to their safe service. The article conducted the internal thermal and compression fatigue tests studies on deicing composite laminates embedding sprayable metal circuit. The internal thermal fatigue test refers to the specimen being subjected to 1000 cycles of temperature from -55 °C to 80 °C and then back to -55 °C. The compression fatigue test refers to the specimen being subjected to 30,000 cyclic loads and 4 static compressive loads. The results indicate that the deterioration of the electro-thermal function of the specimen precedes the damage of the structure. After 1000 thermal cycles, the electrical resistance has been increased by 20.46%, and heating power has been reduced by 17.02%. The compression fatigue effect of low load has a relatively small impact on the increase of resistance value, but the resistance value cannot be restored to its initial state. The compressive residual strength of the specimen after 30,000 compression cycles is about 50 MPa. The fatigue life of the structure was lower than that of the electro-thermal function.