Atomizer nozzle, atomizing device, method for producing metal powder, and metal powder

A method for producing a metal powder using an atomizer nozzle, the method comprising:

• allowing a molten metal to flow downward from a lower end of a molten metal nozzle of the atomizer nozzle extending in a vertical direction;
• introducing a gas into a gas nozzle of the atomizer nozzle including a chamber having an inner peripheral surface surrounding an outer periphery of e molten metal nozzle from a blow portion introducing the s toward a circumferential direction of the molten metal nozzle;
• and
• applying a swirling flow to the introduced gas by a cover, the cover extending from the chamber to a position below the lower end of the molten metal nozzle while surrounding the molten metal nozzle, the cover being provided with a tapered inner peripheral surface connected to the inner peripheral surface of the chamber and having a diameter which decreases toward a lower end portion of the tapered inner peripheral surface, such that the gas is brought into contact with the molten metal to atomize the molten metal,
• wherein the cover is further provided with a diameter expansion surface which is connected to the lower end portion of the tapered inner peripheral surface and has a diameter which increases toward a lower end portion of the diameter expansion surface.