Physics of Magnetism and Magnetic Materials
Mã số tài liệu:
4921
Đơn giá:
0
NHẤN VÀO ĐỂ TẢI
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Tác giả: K.H.J. Buschow Thể Loại: Physical Nhà xuất bản: N/A Số trang: 191 Định dạng: PDF Dung Lượng: 6.37 MB
Giới thiệu: More serious efforts to use the power hidden in magnetic materials were made only much later. For instance, in the 18th century smaller pieces of magnetic materials were combined into a larger magnet body that was found to have quite a substantial lifting power. Progress in magnetism was made after Oersted discovered in 1820 that a magnetic field could be generated with an electric current. Sturgeon successfully used this knowledge to produce the first electromagnet in 1825. Although many famous scientists tackled the phenomenon of magnetism from the theoretical side (Gauss, Maxwell, and Faraday) it is mainly 20th century physicists who must take the credit for giving a proper description of magnetic materials and for laying the foundations of modem technology. Curie and Weiss succeeded in clarifying the phenomenon of spontaneous magnetization and its temperature dependence. The existence of magnetic domains was postulated by Weiss to explain how a material could be magnetized and nevertheless have a net magnetization of zero. The properties of the walls of such magnetic domains were studied in detail by Bloch, Landau, and Néel.
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