Annualing separation agent for producing grain-oriented silicon steel with smooth surface and good magnetic property

Abstract

An annealing separator for manufacturing grain-oriented silicon steel with mirror-like surface having good magnetic performance consists of the composition of which is 77˜98 by wt % of Al 2 O 3 powder, 1˜8 by wt % of alkaline earth powder, 1˜15 by wt % of alkali metal chloride and/or alkaline earth metal chloride. The annealing separator of the invention can avoid forming a glass-film undercoating on the surface of the steel sheet during high-temperature annealing, and at the same time, the oxide embedded at near-surface of the sheet is removed by means of corrosive reaction of the chloride, so that a produce with smooth surface and stable magnetic performance is obtained.

1 . An annealing separator for manufacturing a grain-oriented silicon steel with good magnetic performance, which consists of a composition as follows:
 77˜98% by weight of Al 2 O 3  powder;   1˜8% by weight of alkaline earth metal oxide powder;   1˜15% by weight of alkali metal chloride and/or alkaline earth metal chloride.   
     
     
         2 . The annealing separator for manufacturing a grain-oriented silicon steel with good magnetic performance according to  claim 1 , wherein the alkaline earth metal oxide comprises BeO, MgO, CaO, SrO or BaO. 
     
     
         3 . The annealing separator for manufacturing a grain-oriented silicon steel with good magnetic performance according to  claim 1 , wherein the alkali metal chloride comprises LiCl, NaCl, KCl or RbCl. 
     
     
         4 . The annealing separator for manufacturing a grain-oriented silicon steel with good magnetic performance according to  claim 1 , wherein the alkaline earth metal chloride comprises BeCl 2 , MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2  or ZnCl 2 .