Electrical steel sheet laminate having high stacking factor and comprising a polymeric adhesive layer comprising nanoparticles of SiO2, TiO2 and/or ZnO
The present invention relates to an electrical steel sheet laminate, and provided is an electrical steel sheet laminate comprising: a plurality of electrical steel sheets; and polymer adhesive layers positioned between the electrical steel sheets, wherein the coating thickness of the polymer adhesive layers is 1.8-5.4 μm, the space factor of the laminate is 95.8-98.5%, and the following mathematical formula 1 is satisfied. [Mathematical Formula 1] 172.4≤space factor (%)×thickness (μm)≤531. 172.4≤space factor (%)×thickness(μ m )≤531 [Equation 1]
1 . An electrical steel sheet laminate comprising:
a plurality of electrical steel sheets; and
a laminate including a polymer adhesive layer positioned between the electrical steel sheets,
wherein the polymer adhesive layer includes 70 to 95 wt % of resin and 5 to 30 wt % of at least one inorganic nanoparticles among SiO 2 , TiO 2 , and ZnO,
wherein the coating thickness of the polymer adhesive layer is 1.8 to 5.4 μm,
a stacking factor of the laminate is 95.8 to 98.5%, and
Equations 1 and 2 below are satisfied:
172.4≤stacking factor×thickness(μ m )≤531 [Equation 1]
40≤shear adhesive strength( MPa )×high temperature adhesive strength( MPa )≤130 [Equation 2]
(wherein the shear adhesive strength is a value measured in accordance with the ISO 4587 standard after preparing two specimens (thickness: 0.27 mmt, size: 100×25 mm), and
wherein high-temperature adhesive strength is measured in accordance with ISO 4587 standard under the condition of 150° C.).
2 . The electrical steel sheet laminate of claim 1 , wherein: shear adhesive strength of the laminate is 4.8 to 17.9 MPa.
3 . The electrical steel sheet laminate of claim 1 , wherein: high-temperature adhesive strength of the laminate is 5 to 7.2 MPa.
4 . The electrical steel sheet laminate of claim 1 , wherein: surface insulation resistance of the polymer adhesive layer in the laminate is 90 to 160 Ω.
5 . The electrical steel sheet laminate of claim 1 , wherein: an inorganic content in the polymer adhesive layer in the laminate is 5 to 30 wt %.
6 . The electrical steel sheet laminate of claim 1 , wherein: an anti-sticking temperature of the polymer adhesive layer in the laminate is 110 to 195° C.
7 . The electrical steel sheet laminate of claim 1 , wherein: an anti-automatic transmission fluid (ATF) temperature of the laminate is 150 to 190° C.
8 . The electrical steel sheet laminate of claim 1 , wherein n: tensile adhesive strength of the laminate is 1.2 to 13 N/mm 2 .
9 . A method of manufacturing an electrical steel sheet laminate of claim 1 , the method comprising:
forming a polymer adhesive layer on an electrical steel sheet by applying a coating composition including 70 to 95 wt % of resin and 5 to 30 wt % of at least one inorganic nanoparticles among SiO 2 , TiO 2 , and ZnO as a solid content to a steel sheet, curing the coating composition by heat treatment, and adjusting pressure of a roll coater and the steel sheet to 50 to 1500 kgf for steel sheet with an area of 50 mm×50 mm when the coating composition is applied; and
laminating the electrical steel sheet on which the polymer adhesive layer is formed.