How dielectric material choice shapes ionic wind output, durability, and heat in DBD plasma actuators. Compare Kapton, PTFE, glass, and ceramics. Book a.
TL;DR: In a DBD plasma actuator, the dielectric barrier is not a passive spacer. It sets the ionic wind you get, how long the device survives, and how much heat it dumps into the substrate. Polymers like Kapton and PTFE are easy to prototype with but erode under sustained discharge; glass and engineered ceramics trade a harder drive for far better lifetime and thermal behavior.
A dielectric barrier discharge (DBD) plasma actuator is deceptively simple: two electrodes offset across a thin insulating layer, driven with a high-voltage AC waveform. The insulator between them, the dielectric barrier, is what makes the discharge self-limiting instead of an arc. But treating it as a generic insulator is a mistake. Its permittivity, thickness, thermal conductivity, and resistance to erosion each move the actuator's performance in different directions. If you want the background on how the discharge itself produces thrust, start with our primer on how DBD plasma actuators work, then come back here for the material trade study.
For cooling applications, the stakes are specific. The whole point of ionic wind solid-state cooling is to move air with no moving parts. The dielectric determines how much air you move per watt, and whether the device still works after months of continuous operation.
Most published actuators use one of a short list of materials: Kapton (polyimide) tape, PTFE (Teflon), glass or quartz, PMMA, and machinable or sintered ceramics such as Macor and alumina (Al2O3). A recent review of DBD actuators notes that the majority of authors default to Kapton, Teflon, Macor, or PMMA, largely because they are cheap, thin, and easy to work with in a lab [1].
Two material properties dominate the trade-off:
Permittivity (dielectric constant). Higher permittivity generally couples more of the applied field into the air gap, which tends to raise the electrohydrodynamic (EHD) body force and therefore the induced wind. Controlled experiments on surface actuators found that a glass-reinforced epoxy with the highest dielectric constant among the samples produced higher induced velocities than either PTFE or Kapton at the same thickness, and that thinner dielectrics outperformed thicker ones at a given drive voltage [2]. The effect is not perfectly monotonic across every study, some quartz simulations show a fall-off at very high permittivity, but the practical rule holds: within a material family, thinner and higher-k pushes more air, up to the point where breakdown limits you.
Thickness. Thinner barriers raise the field in the gap and lower the ignition voltage, but they also reduce the margin before dielectric breakdown and puncture. This is the central tension in actuator design: the same change that boosts ionic wind erodes your safety margin.
Ease of prototyping is why Kapton is everywhere, and durability is why it rarely ships. In accelerated testing of alternative dielectric materials, Kapton and PMMA showed weak resistance to the high stresses in the discharge region, while glass and alumina ceramic held constant behavior throughout the test campaign [3]. The failure mode is physical: sustained micro-discharges chemically attack and pit the polymer surface, roughening it until the discharge becomes non-uniform and the actuator's output drifts down.
This matters more for cooling than for aerodynamics. An aircraft flow-control actuator may only fire during specific flight phases. A cooling actuator on an edge AI board or an optical module is expected to run continuously for the life of the product. Erosion that is a footnote in a wind-tunnel paper becomes a field-return in a thermal product. Reliability, and the related ozone question, is worth understanding on its own terms, which we cover in ionic wind reliability and ozone, explained.
Cooling devices have an ironic problem: the actuator itself dissipates power and heats up. The dielectric's thermal conductivity governs whether that heat spreads into the substrate or pools at the discharge. The contrast is stark, copper conducts around 385 W/m K while Kapton film sits near 1.57 W/m K, so a polymer barrier behaves as a local thermal insulator right where the discharge is hottest [1].
Engineered ceramics let you tune this directly. In a study of sintered ceramic barriers, three formulations driven at 10 kVpp produced very different power draws and surface temperatures: yttria-stabilized zirconia reached 20.7 W and 155 C, magnesia-calcium zirconate 9.6 W and 62 C, and magnesia-alumina just 5.6 W and 47 C [4]. Same geometry, same drive, a nearly fourfold spread in dissipated power and a 108 C spread in ceiling temperature, purely from material chemistry. For a cooling actuator, that difference is the design.
There is no single best dielectric; the right answer depends on what the actuator has to do.
For lab prototyping and fast iteration, Kapton and PTFE are fine. They are thin, forgiving, and let you sweep geometry cheaply, as long as you do not read durability or absolute efficiency off a polymer build.
For continuous-duty cooling in a real product, a glass or engineered-ceramic barrier is the defensible choice. You accept a higher drive voltage and harder fabrication in exchange for stable output, low erosion, and a thermal path you can actually design around. A low-loss ceramic such as an alumina- or magnesia-based composite keeps both dissipated power and ceiling temperature down, which is exactly what a thermal device needs.
For maximum ionic wind at fixed voltage, go thin and higher-permittivity, then verify you still have breakdown margin under worst-case humidity and temperature.
At YPlasma this is why we treat the dielectric as a core part of the actuator, not an off-the-shelf tape. A hybrid dielectric that combines the manufacturability of a film with the durability and thermal behavior of a ceramic is how solid-state ionic wind moves from a wind-tunnel curiosity to a component you can put on a board and forget about.
The materials science is the leverage point for the whole field. Better dielectrics mean lower drive voltages, longer life, and more airflow per watt, which is what it takes to compete with a fan on the metrics that matter. If you are evaluating solid-state cooling for edge AI, GPUs, or optical modules and want to see how a purpose-built dielectric performs against your thermal budget, book a demo and we will walk through the numbers for your case.
[1] "DBD Plasma Actuators for Aerodynamic Flow Control: A Review," Applied Sciences, MDPI, 2026. https://www.mdpi.com/2076-3417/16/4/1888
[2] "Effect of permittivity and frequency on induced velocity in ac-DBD surface and channel plasma actuators," Sensors and Actuators A: Physical. https://www.sciencedirect.com/science/article/pii/S0924424719315183
[3] "Experimental Analysis of Alternative Dielectric Materials for DBD Plasma Actuators," ASME IMECE 2018. https://asmedigitalcollection.asme.org/IMECE/proceedings-abstract/IMECE2018/52002/V001T03A005/275304
[4] "Long-lasting ceramic composites for surface dielectric barrier discharge plasma actuators," ResearchGate. https://www.researchgate.net/publication/371094535_Long-lasting_ceramic_composites_for_surface_dielectric_barrier_discharge_plasma_actuators