Grain-oriented electrical steel sheet

Abstract

Provided is a grain-oriented electrical steel sheet having magnetic properties that can sufficiently decrease the building factor. The grain-oriented electrical steel sheet includes a base steel sheet containing Si: 1.50 mass % to 8.00 mass %, Mn: 0.02 mass % to 1.00 mass %, and Co: 0.005 mass % to 0.050 mass %, and a base film mainly composed of forsterite, formed on the surface of the base steel sheet. Ti content in the base steel sheet and the base film as a whole is 0.0050 mass % to 0.0200 mass %. When R17 is the ratio of hysteresis loss Wh17 to iron loss W17/50 when excited at 1.7 T, and R19 is the ratio of hysteresis loss Wh19 to iron loss W19/50 when excited at 1.9 T, then 0.30≤R17≤R19 is satisfied.

1 . A grain-oriented electrical steel sheet comprising a base steel sheet containing Si: 1.50 mass % to 8.00 mass %, Mn: 0.02 mass % to 1.00 mass %, and Co: 0.005 mass % to 0.050 mass %, and a base film mainly composed of forsterite, formed on the surface of the base steel sheet, wherein
 Ti content in the base steel sheet and the base film as a whole is 0.0050 mass % to 0.0200 mass %, and   the following expression (1) is satisfied, where R17 is the ratio of hysteresis loss Wh 17  to iron loss W 17/50  when excited at 1.7 T and R19 is the ratio of hysteresis loss Wh 19  to iron loss W 19/50  when excited at 1.9 T,   
       
         
           
             
               
                 
                   
                     
                       
                         0 
                         . 
                         3 
                       
                       ⁢ 
                       0 
                     
                     ≤ 
                     
                       R 
                       ⁢ 
                       17 
                     
                     ≤ 
                     
                       R 
                         
                       19. 
                     
                   
                 
                 
                   
                     ( 
                     1 
                     ) 
                   
                 
               
             
           
         
       
     
     
         2 . The grain-oriented electrical steel sheet according to  claim 1 , wherein Ti content in the base steel sheet is 0.0030 mass % or less. 
     
     
         3 . The grain-oriented electrical steel sheet according to  claim 1 , further comprising an insulating coating on the surface of the base film. 
     
     
         4 . The grain-oriented electrical steel sheet according to  claim 1 , wherein the base steel sheet further contains one or more selected from the group consisting of Sn: 0.500 mass % or less, Cr: 0.500 mass % or less, Cu: 0.50 mass % or less, Ni: 0.50 mass % or less, Bi: 0.500 mass % or less, P: 0.500 mass % or less, Sb: 0.500 mass % or less, Mo: 0.500 mass % or less, B: 25.0 mass ppm or less, Nb: 0.020 mass % or less, V: 0.020 mass % or less, As: 0.0200 mass % or less, Zn: 0.020 mass % or less, Pb: 0.0100 mass % or less, W: 0.0100 mass % or less, Ga: 0.0050 mass % or less, and Ge: 0.0050 mass % or less. 
     
     
         5 . The grain-oriented electrical steel sheet according to  claim 2 , further comprising an insulating coating on the surface of the base film. 
     
     
         6 . The grain-oriented electrical steel sheet according to  claim 2 , wherein the base steel sheet further contains one or more selected from the group consisting of Sn: 0.500 mass % or less, Cr: 0.500 mass % or less, Cu: 0.50 mass % or less, Ni: 0.50 mass % or less, Bi: 0.500 mass % or less, P: 0.500 mass % or less, Sb: 0.500 mass % or less, Mo: 0.500 mass % or less, B: 25.0 mass ppm or less, Nb: 0.020 mass % or less, V: 0.020 mass % or less, As: 0.0200 mass % or less, Zn: 0.020 mass % or less, Pb: 0.0100 mass % or less, W: 0.0100 mass % or less, Ga: 0.0050 mass % or less, and Ge: 0.0050 mass % or less. 
     
     
         7 . The grain-oriented electrical steel sheet according to  claim 3 , wherein the base steel sheet further contains one or more selected from the group consisting of Sn: 0.500 mass % or less, Cr: 0.500 mass % or less, Cu: 0.50 mass % or less, Ni: 0.50 mass % or less, Bi: 0.500 mass % or less, P: 0.500 mass % or less, Sb: 0.500 mass % or less, Mo: 0.500 mass % or less, B: 25.0 mass ppm or less, Nb: 0.020 mass % or less, V: 0.020 mass % or less, As: 0.0200 mass % or less, Zn: 0.020 mass % or less, Pb: 0.0100 mass % or less, W: 0.0100 mass % or less, Ga: 0.0050 mass % or less, and Ge: 0.0050 mass % or less. 
     
     
         8 . The grain-oriented electrical steel sheet according to  claim 5 , wherein the base steel sheet further contains one or more selected from the group consisting of Sn: 0.500 mass % or less, Cr: 0.500 mass % or less, Cu: 0.50 mass % or less, Ni: 0.50 mass % or less, Bi: 0.500 mass % or less, P: 0.500 mass % or less, Sb: 0.500 mass % or less, Mo: 0.500 mass % or less, B: 25.0 mass ppm or less, Nb: 0.020 mass % or less, V: 0.020 mass % or less, As: 0.0200 mass % or less, Zn: 0.020 mass % or less, Pb: 0.0100 mass % or less, W: 0.0100 mass % or less, Ga: 0.0050 mass % or less, and Ge: 0.0050 mass % or less.