Properties of MgAl₂O₄ doped alumina barrier layers for dielectric barrier discharge

Abstract

In the current work, we studied the effect of multiphasic dielectric material on coplanar dielectric barrier discharge. To enhance the application potential of standard alumina () ceramic barriers, composite materials composed of immiscible and Mg-spinel () phases were prepared and investigated. The effect on coplanar dielectric barrier discharge was studied in a broad concentration profile of the composite materials ranging from 0 to 100 vol.% in an alumina matrix. The study was mainly focused on the determination of ignition voltage as a crucial parameter for industrial applications. The minimum ignition voltage was found in the ceramic composite with 15 vol.% . We also noticed differences in plasma filament localization on the ceramic surfaces of different composites. This work also brings comprehensive investigation of the electrical and microstructural properties of this biphasic barrier material. Detailed investigation revealed that the ignition voltage was a nontrivial combination of both bulk (phase and chemical compositions) as well as surface (phase distribution, grain size, surface roughness) properties of the barrier materials.

Complex characterisation of Cr-doped α-Al 2O3 for DBD applications

“…The averaged profiles of ϵ r for various concentrations of Cr 2 O 3 are shown in figure 9, where error bars were removed for better clarity 4 . The section of the relative permittivity with respect to the concentration of Cr We can see that the relative permittivity does not significantly differ from pure Al 2 O 3 or ELC ceramics compared to results published in [22,38], where doping of Al 2 O 3 by MgAl 2 O 4 or Li 1+ respectively lead to an increase of the dielectric constant up to several hundred. Besides some small fluctuations, values of the relative permittivity of samples used for 4 The missing data for 21 kHz were caused by an internal error of the device during automated measurement.…”

“…The ceramic substrates were prepared using the gel-tape casting method described in detail in [22,27], here just a brief description is given. The aluminium oxide powder (TM-DAR, Taimei Chemicals, Japan) and chromium (III) oxide powder (Sigma-Aldrich, Germany) were used.…”

“…Recently, we have investigated properties of Al 2 O 3 doped with MgAl 2 O 4 [22]. It forms a bi-phasic material, where MgAl 2 O 4 spinel forms islands in Al 2 O 3 ceramics.…”

Thin high-strength zirconia tapes with extreme flexibility

“…Thin self-supporting ceramic tapes with the thickness in the range from tens to hundreds of microns are used in many industrial applications (ceramic barrier layers [1][2][3][4], sensors [5][6][7], and flexible substrates [8,9]). Due to the subtle thickness of ceramic tapes, it is possible to reach an unusually high strength of ceramic tapes and even their substantial elastic deformations [8,9].…”

Robust current peak detection method for dielectric barrier discharges

“…permittivity, loss tangent, etc, and the discharge properties on the ceramics such as ignition and quenching voltage. One of the first systematic studies were introduced in [13,14,17], where the impact of magnesium on the ignition and quenching voltages was studied. Such measurement requires a proper method also suitable for further statistical processing.…”