Analysis and experimental characterisation of electrical insulators and industrial adhesives bonded to conventionally produced and screen-printed electrical steel sheets

To further mitigate core magnetic losses, ongoing research is constantly devoted to improving materials and processes for the production of electrical steel. The first part concerns an initial overview of the theoretical concepts of electromagnetism, defining the main notions that give rise to the phenomena discussed later. Then, the initial objective was to first investigate the individual laminations, going on to electromagnetically characterise both the base material and the insulating/adhesive coating used on them. After this in-depth investigation and comparison, we moved on to define the main objective of this work, namely the characterisation and qualification of lamination packages consisting of five laminations each. In fact, the main purpose of this last part was to observe the magnetic losses of each individual package, and to note how these varied as three factors varied: base material, insulation/adhesive combination between the individual sheets, and pressure applied to each package. Furthermore, it was important to begin by studying the individual sheet and the individual combination of electrical insulation and adhesive, and then move on to define packages of the same laminates and combinations of coatings. In this way, it was intended to give some continuity to the work, but mainly to observe and understand how the results in terms of magnetic losses and electrical properties of individual sheets, in terms of sheet base material and insulation, affect the magnetic losses of different laminate packages.