HIGH SILICON STEEL SHEET AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A high-silicon steel sheet and a manufacturing method thereof are provided to coat Fe and Si nano particles at normal temperature and normal pressure and to obtain a silicon steel sheet of high efficiency through a short heat treatment process. CONSTITUTION: A high-silicon steel sheet is composed of a central portion and top and underside surface portions. The silicon content of the central portion is 3.5-4.5 wt%. The silicon content of the top and underside surface portions are 4.5-6.5 wt% and become smaller from the surface to the central portion. Silicon content differences between each of the top and underside surface portions and the central portion are 3wt% or less. The high-silicon steel sheet manufacturing method comprises: a step of preparing the silicon steel sheet; a step of forming Fe and Si coating layer by coating Fe and Si nano particles on the top and underside surfaces of the silicon steel sheet; a step of temper-rolling the silicon steel sheet in which the Fe and Si coating layers are formed in the top and underside surfaces; and a step of forming the top and underside surface portions which silicon content becomes smaller to the central portion.