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    The development history of nd-ferroboron

    Release date: August 13, 2012

    5, 000 years ago humans discovered the natural magnet (Fe3O4)

         2300 years ago the Chinese natural magnet type ground into a spoon on the smooth surface, under the action of magnetic, spoon handle guide, yue "SiNa" this is known as the world's first guide apparatus.
         The Chinese made the world's earliest compass by rubbing magnets with iron needles 1,000 years ago.
         Around 1100, China joined the magnet needle and the square lambda, becoming a magnet guide for navigation.
         1405-1432 zheng he began the great work of navigation in human history with the guide.
         1488-1521 Columbus, gamma, Magellan was made famous for the world's voyages by a guide from China.
         William gilbert, a British man of 1600, published an "magnet" for magnetism, repeating and developing his predecessors' knowledge and experiments on magnetism.
         The French physicist c. coulomb created the "coulomb's law" to describe the force of charge and magnetic poles.
         In 1820, the Danish physicist H.C. auster discovered the magnetic force.
         1831 British physicist m. Faraday discovered electromagnetic induction.
         1873 British physicist J.C. maxwell Τ in his monograph "theory of electric and magnetic" completed the unification of the electromagnetic theory.
         1898-1899 French physicist p. Curie found that ferromagnetism was converted to paramagnetism at certain temperatures (Curie temperature).
         The French physicist P.I. lang's theory of statistical mechanics explains the change in paramagnetism over temperature.
         In 1907, the French physicist P.E. weiss proposed the theory of molecular field, extending the theory of lang.
         In 1921, the Austrian physicist w. pauly suggested that Bohr magneto be the basic single lambda for the magnetic moment of the atom. An American physicist, a. Compton, also has A magnetic moment that spins accordingly.
         In the British physicist P.A.M. Dirac, the quantum mechanics of relativity perfectly explained the intrinsic spin and magnetic moments of electrons. Together with the German physicist w. Heisenberg, the exchange force of the origin of static electricity was demonstrated, and the basis of modern magnetic science was established.
         In 1936, the Soviet physicist lang dao completed the great treatise on theoretical physics, which contains a comprehensive and fascinating chapter on modern electromagnetism and ferromagnetism.
         The concepts and theories of anti-ferromagnetism and ferromagnetism were proposed by the French physicist l. nelle in 1936 to 1948, and in the subsequent years of the study, the understanding of material magnetism was deepened.
         1967 contemporary physicists K.J., Austria knight in quantum magnetism found under the guidance of magnetic energy product of rare-earth magnets (SmCo5) is at an all-time high, which opened up a new era in the development of permanent magnetic material.
         In 1967, Strnat, from Dayton university in the United States, developed the samarium cobalt magnet, which marks the arrival of the era of rare-earth magnets.
         In 1974, the second generation of rare earths, the rare earth magnetic-sm2co17, came out.
         In 1982, the third generation of rare earths was made.
         1990 atomic clearance magnet - sm-fe-n.
         In 1991, German physicist E.F. knoller put forward the theoretical basis of the exchange of double phase composite magnets, and pointed out the development prospect of nanocrystalline magnets.

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