Microwave ndt of exfoliation in a dielectric plate

Abstract

The microwave method is effective for non-destructive testing (NDT) of dielectric and composite materials of industrial products. These products are often designed with multi-layered structures. Defects in form of stratifications can occur during production and exploitation of these products. The typical direct methods of microwave NDT can be used to detect inhomogeneities in materials and to determine some parameters of the structure in a narrow range of their change. The inverse problem is used for quantitative determination of many parameters of the structures of interest. A complex reflection coefficient (CRC) of electromagnetic wave from the investigated object is one of informative parameters in diagnostics. It is possible to calculate electrical parameters and thickness of layers of a dielectric using the known frequency dependence of CRC of electromagnetic waves, which impinge on this stratified structure.