Search

KR-20260062417-A - LAMINATE METHOD OF ELECTRICAL STEEL SHEET AND ELECTRICAL STEEL SHEET LAMINATE

KR20260062417AKR 20260062417 AKR20260062417 AKR 20260062417AKR-20260062417-A

Abstract

The present specification discloses a method for manufacturing a laminate having a height of 90 mm or more and 180 mm or less by laminating electrical steel sheets having a thickness within the range of 0.1 mm or more and 0.65 mm or less, wherein the electrical steel sheets are laminated by rotating them at a certain angle, and the laminate laminated by this method.

Inventors

  • 안용근
  • 정종민
  • 김동유
  • 강춘구

Assignees

  • 현대제철 주식회사

Dates

Publication Date
20260507
Application Date
20241029

Claims (7)

  1. A method of manufacturing a laminate having a height within the range of 45 mm to 300 mm by laminating electrical steel sheets having a thickness within the range of 0.1 mm to 0.65 mm, Electrical steel sheet lamination method for laminating a plurality of electrical steel sheets to satisfy Equation 1 below: [Equation 1] In Equation 1, TT is the height of the laminate, Nx represents the number of laminates of unit steel sheets with an x-angle, and Tx represents the thickness of each electrical steel sheet with an x-angle.
  2. In paragraph 1, A method for laminating electrical steel sheets to manufacture a laminate satisfying the following Equation 2: [Equation 2] In Equation 2, A is the standard deviation of the iron loss value measured at 1° intervals of the laminate.
  3. In paragraph 1, An electrical steel sheet lamination method in which there are two or more types of unit steel sheets having an x-angle, and the unit steel sheets are composed of two or more electrical steel sheets.
  4. A laminate satisfying the following Equation 2: [Equation 2] In Equation 2, A is the standard deviation of the iron loss value measured at 1° intervals of the laminate.
  5. In paragraph 4, The above laminate is a laminate in which a plurality of electrical steel sheets are laminated to satisfy the following Equation 1: [Equation 1] In Equation 1, TT is the height of the laminate, Nx represents the number of laminates of unit steel sheets with an x-angle, and Tx represents the thickness of each electrical steel sheet with an x-angle.
  6. In paragraph 4, A laminate having a height of 45 mm or more and 300 mm or less.
  7. In paragraph 4, A laminate having an electrical steel sheet thickness within the range of 0.1 mm or more and 0.65 mm or less.

Description

Lamination Method of Electrical Steel Sheet and Laminate The present invention relates to a method for laminating electrical steel sheets and a laminate. With environmental regulations tightening globally in recent years, conventional internal combustion engine vehicles are being rapidly replaced by eco-friendly vehicles such as hybrid, electric, and hydrogen cars. Eco-friendly vehicles utilize electric motors to generate the driving force required for the vehicle and can reduce environmental pollution by significantly decreasing the emission of harmful exhaust gases. As interest in and demand for such eco-friendly vehicles increase, the demand for electric motors, which generate the driving force required for the vehicle, is also rising. An electric motor is a device that uses electricity to generate the driving force needed for a vehicle, and energy efficiency—the ability to operate for a longer period using the same amount of energy—is a crucial technical factor. To increase the energy efficiency of such electric motors, it is essential to improve the magnetic performance of the non-oriented electrical steel sheets used as the core material. Non-oriented electrical steel is a material that possesses uniform magnetic properties in all directions regardless of the rolling direction; to enhance energy efficiency, it is necessary to lower iron losses and increase magnetic flux density. In particular, for automotive drive motors, high torque is required during low-speed operation and acceleration, and high rotation (200Hz or higher) is required during constant speed and high-speed driving. Therefore, electrical steel sheets used as core materials for drive motors require low high-frequency iron loss and high magnetic flux density. Magnetic flux density refers to the number of magnetic field lines induced in a material under a specific magnetic field. Generally, the value induced under a magnetic field of 5000 A/m (B50) is evaluated, and the unit used is Tesla (T). Iron loss is the loss that occurs during the magnetization process of the electrical steel sheet material and refers to the sum of hysteresis loss, eddy current loss, and anomalous loss. Methods to improve high-frequency iron loss in electrical steel sheets include adding alloying elements that increase resistivity, such as silicon (Si), manganese (Mn), and aluminum (Al), or reducing eddy current losses by thinning the material. However, if a large amount of elements that increase resistivity is added, problems such as reduced magnetic flux density and rollability may occur due to the increased amount of alloying elements. In addition, major alloying elements and additive elements combine to form precipitates, and in the case of fine precipitates, they can impede magnetic properties by hindering the movement of magnetic domains. Motors are manufactured by laminating non-oriented electrical steel sheets, but even non-oriented electrical steel sheets form fine anisotropy. Therefore, if electrical steel sheets are laminated in the same direction during motor manufacturing, anisotropy is formed, which can result in inferior motor characteristics. In prior art patent document 1, the equipment heats and rotates the squeeze ring while laminating, but is characterized by being able to heat up to the inner diameter of the laminated core, so the purpose is to improve the lamination quality and not to improve magnetic properties. Therefore, there is a need for technology regarding electrical steel sheet laminated cores and lamination methods to improve magnetic properties. Figure 1 is a diagram showing the anisotropy of an electrical steel sheet. Figure 2 is an exemplary drawing of a 30° unit steel plate. Hereinafter, preferred embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention is not limited or restricted by the following embodiments. Additionally, when it is stated that a component (or area, layer, part, etc.) is "on," "connected," or "combined" with another component, it means that it may be directly placed/connected/combined with the other component, or that a third component may be placed between them. Terms such as "include" or "have" are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. In order to clearly explain the present invention, detailed descriptions of related prior art that are irrelevant to the explanation or that may unnecessarily obscure the essence of the invention have been omitted. Furthermore, when assigning reference numerals to the components of each drawing in this specification, identical or similar reference nu