Since the 1990s, development of a precious metal coating technology has been ongoing. In recent years, the research focus has shifted from the consumable refractories (o-rings, tube stirrers etc) to fused cast AZS furnace blocks. This has been driven by glass manufacturers looking for a solution to excessive refractory wear. This wear impacts both furnace life and glass quality. Until recently, the coating could only be applied to machined fused cast AZS surfaces. This paper details the latest innovation of applying the coating to the "as-cast" surface of fused cast AZS blocks and includes micro-graphical analysis and comparison of "as-cast" and "machined" AZS surfaces, details of the latest innovations in the laser pre-treatment process, and results of a three-year plant trial.
