Abstract

We present the results of a study that confirms the high efficiency of using surface microwaves in assessing the extent of exfoliation of dielectric and magnetodielectric coatings from a metal base. The complex coefficient of attenuation of the field of a surface electromagnetic wave along the normal to the coating surface is used as a parameter for estimating the extent of exfoliation. In contrast to the existing approaches, the developed electrodynamic measurement model takes into account the real and imaginary parts of the complex dielectric permittivity and magnetic permeability of the coating with allowance for their frequency dispersion; this improves the accuracy and reliability of estimating the extent of exfoliation. An algorithm is developed for estimating the extent of coating exfoliation based on the search for the maximum joint probability density of the coefficient of attenuation of the field of a surface electromagnetic wave measured at a set of frequencies. We introduce and substantiate a statistical limit of the resolution of two values of exfoliation; this makes it possible to evaluate the possibility of discriminating between two close values of exfoliation depending on the bandwidth of attenuation coefficient measurements, their number, and the signal-to-noise ratio. The structure of a measuring complex that implements the proposed approaches to exfoliation assessment is provided. Numerical and field experiments have shown the fundamental possibility of estimating the value of recorded values of exfoliation of dielectric and magnetodielectric coatings from a metal substrate with a thickness of 20 μm or less in the frequency band of 9–13.5 GHz.

中文翻译：

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用表面微波估算介电和磁介电涂层的剥落程度

摘要

我们提出了一项研究结果，该研究证实了使用表面微波来评估介电涂层和磁介电涂层从金属基材上剥落的程度非常有效。沿着涂层表面的法线的表面电磁波的场的衰减的复数系数被用作估计剥落程度的参数。与现有方法相反，开发的电动力学测量模型考虑了涂层的复介电常数和磁导率的实部和虚部，并考虑了它们的频率色散。这提高了估计剥落程度的准确性和可靠性。开发了一种算法，用于基于在一组频率下测量的表面电磁波场的衰减系数的最大联合概率密度的搜索来估计涂层剥落的程度。我们介绍并证实了两个去角质值的分辨率的统计极限；这使得可以评估根据衰减系数测量的带宽，其数量和信噪比在两个接近的剥离值之间进行区分的可能性。提供了一种测量综合体的结构，该结构实施了建议的剥离评估方法。