Rational design and multi-step sprayed preparation of concentration gradient CNT@WPU electrothermal coatings for the highly efficient anti-/de-icing performance

Electrothermal anti-/de-icing technology is considered to be an effective means of solving the icing problem on the composite surface of multi-electric/pure-electric vehicle in the future. The electrothermal coating with carbon nanotube concentration gradient was fabricated by the multi-step spraying method, which obviously increased the rate of electric heating by inducing directional heat transfer. The coating temperature remained above 0 ℃ under various low-temperature incoming conditions, when the electric power density as low as 0.4 W/cm 2 . Meanwhile, the concentration gradient coating’s excellent adhesion and electrothermal stability ensured its long service life. Moreover, the surface temperature of the coating on the airfoil model increased rapidly to over 50 ℃ within 180 s at an initial electrical power density of 1.2 W/cm 2 , effectively preventing ice formation on the leading edge for 60 s under −15 °C, 30 m/s flow condition. Under the same conditions, 8.5 mm-thick ice on the leading edge could be swiftly removed within 22 s with initial electrical power density of 1.8 W/cm 2 . This strategy of conductive packing gradient design will provide new insights for advanced electrothermal anti-/de-icing material manufacturing.