ANNEALING METHOD FOR ENLARGING AGGREGATE OF PRIMARILY RECRYSTALLIZED GRAINS WHICH INTRODUCES HIGH MAGNETIC FLUX DENSITY AND ULTRA-LOW IRON LOSS OF ONE DIRECTIONAL ELECTROMAGNETIC STEEL PLATE

摘要

PURPOSE:To obtain one directional electromagnetic steel plates having a stable high magnetic flux density and an ultra-low iron loss, by combining aggregates of primarily recrystallized grains to secondarily recrystallized unclei by heating silicon bearing steel plates at high temperature in a short time after a decarburizing annealing which also works as a primary recrystallization annealing is performed on silicon bearing steel plates. CONSTITUTION:A hot rolled plate of a silicon bearing steel is cold rolled for more than one time and by the cold rolling the primary recrystallization annealing is performed. The cold rolled plate is then subjected to a decarburizing annealing treatment. In the final stage of the process of after the process is performed, the surface layer of the steel plate is repeatedly heated at high temperature in a short time. In this way, aggregates of primarily recrystallized grains in the surface layer having an orientation of (110)[001]are combined to secondarily recrystallized unclei having the same orientation (100)[001]. In this way aggregates of primarily recrystallized grains are enlarged, and one directional electromagnetic steel plates having a stable high magnetic flux density and an ultra-low iron loss can be manufactured constantly.