| 摘要 |
PURPOSE:To convert molten metal directly to amorphous powder in the stage of putting the drops of the molten metal into collision against a metallic rotary body and solidifying the same quickly by parting the molten metal beforehand with a high speed revolving roll of small wettability. CONSTITUTION:The molten metal 2 in a crucible 1 is supplied from the sprue of the bottom of the crucible through a nozzle 33 to a roll 4 provided below the same. At least the surface of the roll 4 consists of a material of small wettability on which the metal 2 is hard to stick and which can release said metal by parting the same instantaneously to fine particles, for example, graphite, TiN or the like. The roll 4 may be one or two facing each other. It is revolved at >=2m/sec peripheral speeds and the metal 2 is pressurized negative by the peripheral speed of the roll 4 considerably higher than the dropping speed thereof, by which cavitation is generated and the metal is parted to fine drops 6. Then, the drops 6 are put into collision against a metallic rotary body 7 revolving at >=10m/sec peripheral speeds, whereby they are quickly solidified and metallic powder 8 is obtd. |
