Mechanical treatment of aluminum plate surfaces for improvements of capacitance and dielectric permittivity

Abstract

The surface mechanical alloying (SMA) technique achieved high capacitances, improved capacitance (C) and dielectric permittivity (ε′) of mixed Aluminum/fiber-glass ‘Al/F-glass’ formed on aluminum plates. The radiofrequency RF range 0.1–106 Hz was applied on the Al/F-glass on Al plates, acting as parallel electrodes sandwiching the mixed ceramic Al/F-glass as dielectric. Capacitance increase observed after surface alloying on treated Al with small 1.5 balls than 6 mm balls on Al-plate & 1 A l-plate 2 respectively, giving twice the permittivity constant of the annealed Al. Deformation micro-scale cavities in Al surfaces played important role in raising capacitance and permittivity values; Interpreted as condensers inside a condenser caused capacitance increase according Maxwell-Wagner-Sillars effect. Dielectric relaxation model Havriliak-Negami Model was used to examine the occurrence of the Maxwell-Wagner-Sillars effect in alloyed Al/F-glass surfaces on Al plates, which confirms micro-cavities important role due to pre-treatment of Al surfaces.