Method for manufacturing electrical steel sheet product
A method for manufacturing an electrical steel sheet product according to an exemplary embodiment of the present invention includes: preparing an adhesive coating composition; forming an adhesive coating layer by applying and then curing the adhesive coating composition onto a surface of an electrical steel sheet; forming a heat-fused layer by laminating and heat-fusing a plurality of electrical steel sheets on which the adhesive coating layers are formed; and cooling the heat-fused electrical steel sheets at a cooling rate of 0.05 to 20° C./min.
1. A method for manufacturing an electrical steel sheet product, the method comprising:
preparing an adhesive coating composition;
forming an adhesive coating layer by applying and then curing the adhesive coating composition onto a surface of an electrical steel sheet;
forming a heat-fused layer by laminating and heat-fusing a plurality of electrical steel sheets on which the adhesive coating layers are formed; and
cooling the heat-fused electrical steel sheets at a cooling rate of 0.05 to 20° C./min,
wherein:
in the cooling of the heat-fused electrical steel sheets at the cooling rate of 0.05 to 20° C./min,
a holding pressing force is 1,000 N/mm 2 or less,
the adhesive coating composition contains an organic/inorganic complex and an inorganic substance,
the organic/inorganic complex comprises an organic resin and an inorganic nanoparticle,
the inorganic nanoparticle is at least partially substituted for a functional group of the organic resin,
the organic resin is a water-soluble epoxy resin,
the water-soluble epoxy resin is a multifunctional epoxy resin having three or more epoxy groups, and the water-soluble epoxy resin has a weight average molecular weight of 1,000 to 50,000, a softening temperature (Tg) of 70 to 120° C., and a solid fraction of 10 to 50 wt %,
the inorganic nanoparticle includes one or more of SiO 2 , TiO 2 , ZnO, Al 2 O 3 , MgO, CaO, and ZrO 2 , and
the inorganic substance is phosphoric acid (H 3 PO 4 ) or sodium hydroxide (NaOH).
2. The method of claim 1 , wherein:
the holding pressing force is 500 N/mm 2 or less and the cooling rate is 0.05 to 1° C./min.
3. The method of claim 1 , wherein:
in the cooling of the heat-fused electrical steel sheets at the cooling rate of 0.05 to 20° C./min,
a cooling finish temperature is 10 to 100° C.
4. The method of claim 1 , wherein:
the inorganic nanoparticle is substituted in the organic/inorganic complex in an amount of 1 to 60 parts by weight with respect to 100 parts by weight of the organic resin.
5. The method of claim 1 , wherein:
the inorganic substance is contained in an amount of 1 to 70 parts by weight with respect to 100 parts by weight of a solid content of the organic/inorganic complex.
6. The method of claim 1 , wherein:
the forming of the adhesive coating layer
is performed in a temperature range of 200 to 600° C.
7. The method of claim 1 , wherein:
in the forming of the adhesive coating layer,
a ratio of the inorganic substance to an organic substance in the adhesive coating layer is 0.05 to 0.6.
8. The method of claim 1 , wherein:
in the forming of the heat-fused layer,
a pressing force is 1 to 2,000 N/mm 2 , a pressing time is 1 to 180 minutes, and a pressing temperature is 100 to 300° C.
9. The method of claim 1 , wherein:
the inorganic nanoparticle includes one or more of Al 2 O 3 , MgO, CaO, and ZrO 2 .