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In this paper, screen-printed electrodes are asymmetrically fabricated on three different dielectrics (multi-layered polyimide, quartz, and alumina). Supplied with AC power, sustainable surface dielectric barrier discharge (SDBD) plasma is generated in atmospheric pressure. During plasma processing, different changes of material degradation and discharge images are observed. The corresponding electrical and optical characteristics are investigated by optical emission spectra (OES) and Lissajous figure analysis, respectively. It is found that both dielectric degradation and electrode erosion occur on the surface of the polyimide based SDBD device, while there is only electrode erosion for the quartz and alumina based devices, which results in different changes of electrical characteristics. OES calculated results show that with an increase of discharge aging time, electron temperature increases for the polyimide based SDBD device and decreases for quartz and alumina based SDBD devices, while all the gas temperatures of three dielectrics increase with the aging time. Furthermore, compared to vibrational temperature and gas temperature, the distribution of electron temperature is more suitable for evaluating the changes in discharge uniformity during plasma processing.

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Surface dielectric barrier discharge (SDBD) is widely applied in the field of active flow control. Its carrier is usually called plasma actuator (PA). However, it has a key drawback of short discharge lifetime due to the dielectric degradation under plasma processing. In this paper, polyimide (PI) film incorporated with Al2O3 nanoparticles is fabricated and used as dielectric of PA. Dielectric material, plasma, surface temperature, discharge characteristics as well as its performance are experimentally studied and compared with those of a conventional pure PI based control actuator. The results show that at sine peak to peak voltage of 8 kV and 6 kHz frequency, the force efficiency of new designed actuator is 2.5 times higher than that of the control actuator after 30 h discharge. Besides, the discharge lifetime is also 3.2 times as long. In the discharge region, the surface of the control actuator appears serious dielectric degradation, which is accompanied by heat accumulation as well as an increase of gas temperature and electron temperature. While for the new actuator, after selective plasma etching, the inorganic Al2O3 nanoparticles can continuously resist the discharge plasma and contributes to effective heat dissipation and more stable plasma parameters.