Presented results of active resistance frequency dependence measurements of a circular cross-section aluminum and copper conductors with a various diameter in a wide frequency range from 20Hz to 2MHz. Using the skin effect simulation we show that for all types of wires an increased active resistance observed, compared to the theoretical values in the frequency range above 200 kHz, where the skin layer thickness becomes less than 200 μm. This phenomenon may be associated with the manufacturing process of a metal wire by drawing through a die, when defects are formed in the near-surface layer, leading to its increased resistivity.

The formation of a surface layer with silver and sodium concentration gradients in K8-grade glasses as a result of ion exchange is demonstrated by scanning electron microscopy (SEM) and electron probe X-ray microanalysis. The silver ions enriched layers with different thicknesses, depending on the duration of the ion exchange from the silver melt, are visualized in the secondary electrons mode. SEM data on the thickness of the silver enriched layer are in good agreement with the results of calculation from the diffusion equation for silver in glass. The dependence of the silver concentration on the diffusion depth is obtained using elemental composition mapping over the glass cross section. The presence of a layer with a silver concentration gradient leads to formation of a gradient waveguide. Discrete peaks in silver concentration profiles, caused by specific features of mutual diffusion of sodium and silver ions in glasses, are found.