Method of refining magnetic domains of barrier-coated electrical steels using metallic contaminants

摘要

A method is provided for domain refinement of final texture annealed grain-oriented silicon steels by applying to the base coating a barrier coating for sealing the forsterite, removing portions of the base coating to expose a pattern of the underlying silicon steel, applying a metallic contaminant to the steel at least in the areas of the exposed steel which is free of thermal and plastic stresses, and thereafter annealing the steel having the barrier coating and contaminant thereon at time and temperature in a reducing atmosphere to diffuse sufficient and controlled amounts of the metallic contaminant and an element from the barrier coating into the exposed steel to produce a permanent pore to effect heat resistant domain refinement and reduced core loss.