Non-oriented electrical steel sheet and manufacturing method thereof
View Patent ↗A non-oriented electrical steel sheet includes: a base iron ( 1 ); and a tension applying type insulating film ( 2 ) of not less than 1 g/m 2 nor more than 6 g/m 2 on a surface of the base iron ( 1 ). An oxide layer ( 3 ) containing at least one type of oxide selected from the group consisting of Si, Al, and Cr and having a thickness of not less than 0.01 μm nor more than 0.5 μm is formed on the surface of the base iron ( 1 ).
1. A non-oriented electrical steel sheet comprising:
a base iron containing:
Si, Al, and Cr: not less than 2 mass % and not more than 6 mass % in total content,
Mn: not less than 0.1 mass % and not more than 1.5 mass %,
C: equal to or less than 0.005 mass %, and
a balance of Fe and inevitable impurities;
an oxide layer containing Al 2 O 3 or (Al, Cr) 2 O 3 ;
wherein the oxide layer has a thickness of not less than 0.01 μm and not more than 0.5 μm; and
wherein the oxide layer is formed on a surface of the base iron; and
a tension-applying type insulating film of not less than 1 g/m 2 and not more than 6 g/m 2 on the surface of the base iron.
2. The non-oriented electrical steel sheet according to claim 1 , wherein the total content of Al and Cr of the base iron is equal to or more than 0.8 mass %.
3. The non-oriented electrical steel sheet according to claim 1 , wherein the insulating film is formed by baking of a coating solution containing phosphate and colloidal silica.
4. The non-oriented electrical steel sheet according to claim 1 , wherein the insulating film is formed by baking of a coating solution containing boric acid and an alumina sol.
5. The non-oriented electrical steel sheet according to claim 2 , wherein the insulating film is formed by baking of a coating solution containing phosphate and colloidal silica.
6. The non-oriented electrical steel sheet according to claim 2 , wherein the insulating film is formed by baking of a coating solution containing boric acid and an alumina sol.