A Method for Measuring the Degree of Cross-linking of Enamel Coated on a Copper Wire by Means of Laser Reflection

Abstract

A simple optical method has been developed for measuring the degree of cross-linking of enamel coated on a copper wire, which determines the dielectric-physical properties of the wire, e. g., the dielectric dissipation factor Tanδ and glass-transition temperature Tg. An increase in the degree of cross-linking changes the enamel color from light yellow to dark brown, which is the basis for the measurement. A preliminary experiment using samples with various degrees of cross-linking showed that the accuracy of the measurement was within an error of 5%.