Many industries are experiencing an increased demand for new more environmentally friendly products from the market. With the increased focus on sustainability, there is a clear need for the development of process optimization and new materials less harmful to the environment. Lead has for many years been considered a hazardous element; however, it has proven to be difficult to replace in many applications. Hitachi Energy (HE) has an ambitious plan to minimize any use of hazardous substances and materials together with reducing waste material by optimizing manufacturing processes.

The goal of this thesis is to investigate a new glass coating material, used in high voltage surge arresters, as a replacement material for the lead-containing coating used today. The investigation is executed by reviewing previously performed investigation reports and examining process optimization together with new laboratory tests of potential material identified in earlier tests.T

he investigation performed in this thesis has included all process steps needed to apply the passivation lead-free glass coating and preparation for electrical testing of the internal semiconductor metal oxide varistor blocks of a surge arrester. Assessing the passivation glass coating has been done by microscopy and SEM (Scanning Electron Microscope) analysis together with electrical testing.

Keywords: Lead-free glass coating, MOV, Surge Arrester, ZnO varistor, electrostatic spray coating