| 摘要 |
PURPOSE:To improve the magnetic characteristics, especially, the coercive force of the title powder by heating the power to a degree at which the power or powder surface only melts in a state where the powder produced by pulverizing an ingot is scattered. CONSTITUTION:This powder is the powder of an iron-rare earth magnet pulverized to <=200mum in mean particle diameter and contains particles which melt in surface only. The manufacturing method of the powder is such that the powder of the iron-rare earth magnet is blown into an inactivated atmosphere after the powder is passed through a plasma flame. For example, the plasma flame 3 is formed by supplying Ar gas to arcs produced between a tungsten electrode 1 and nozzle 2 and the powder of the raw material (pulverized powder) 5 is supplied into the flame 3 from a supporting port 4. The powder 5 is scattered into an inactivated atmosphere in a pan 6 and the powder 5 is collected after cooling. It is also possible to scatter incombustible oil into the pan 6 and heat the oil. The powder thus obtained has molten and smooth particle surfaces and is free from internal strain. |
