Apparatus for producing metal powder and method of producing metal powder

Patent metadata

Field	Value
Publication number	US-2020261981-A1
Application number	US-201816644915-A
Country	US
Kind code	A1
Filing date	Sep 4, 2018
Priority date	Sep 7, 2017
Publication date	Aug 20, 2020
Grant date	—

Abstract

To provide an apparatus for producing a metal powder and a method of producing a metal powder capable of obtaining a metal powder having a finer particle size of excellent quality. A supersonic combustion flame is intensively injected into a downwardly supplied molten metal, the intensive combustion flame is jetted directly downwardly as a focused jet flow, the focused jet flow thrusts into a turning water flow formed along an inner peripheral surface of a pulverization cooling cylinder whose axis line is inclined from a vertical direction, and an intensive position of the combustion flame is in an open space above the turning water flow.

First claim

1 . An apparatus for producing a metal powder, comprising:
a supply unit that downwardly supplies a molten metal; a combustion flame injection unit that convergently injects a supersonic combustion flame from a combustion flame injection port to the molten metal supplied from the supply unit and jets the convergent combustion flame as a focused jet flow directly downward; and a pulverization device having a pulverization cooling cylinder that forms a revolving water flow along an inner peripheral wall of the pulverization cooling cylinder, which has an axis line that is inclined relative to a vertical direction, and that thrusts the focused jet flow inflowing from an upper opening into the revolving water flow, wherein a convergence position of the combustion flame is in an open space above the opening.

2 . The apparatus for producing a metal powder according to claim 1 , wherein the convergence position of the combustion flame is above the axis line of the pulverization cooling cylinder.

3 . The apparatus for producing a metal powder according to claim 2 , wherein the convergence position of the combustion flame is above a virtual horizontal plane passing through an upper end edge of the pulverization cooling cylinder.

4 . The apparatus for producing a metal powder according to claim 1 , wherein the convergence position is within a range of 15 to 120 mm from a lower end of the combustion flame injection port.

5 . The apparatus for producing a metal powder according to claim 1 , wherein:
an inclination angle of the axis line of the pulverization cooling cylinder with respect to the vertical direction is from 10° to 55°, and a tip of the combustion flame injection port is above a virtual horizontal plane passing through an upper end edge of the pulverization cooling cylinder.

6 . A method of producing a metal powder, the method comprising:
convergently injecting a supersonic combustion flame into a molten metal that is downwardly supplied, and jetting the convergent combustion flame as a focused jet flow directly downward; thrusting the focused jet flow into a revolving water flow formed along an inner peripheral surface of a pulverization cooling cylinder having an axis line that is inclined relative to a vertical direction; and configuring a convergence position of the combustion flame in an open space above the revolving water flow.

7 . The method of producing a metal powder according to claim 6 , wherein the convergence position of the combustion flame is above the axis line of the pulverization cooling cylinder.

8 . The method of producing a metal powder according to claim 7 , wherein the convergence position of the combustion flame is above a virtual horizontal plane passing through an upper end edge of the pulverization cooling cylinder.

9 . The method of producing a metal powder according to claim 6 , wherein an airflow flows into an upstream portion of the focused jet flow from all sides.

10 . The method of producing a metal powder according to claim 6 , wherein:
an inclination angle of the axis line of the pulverization cooling cylinder with respect to the vertical direction is from 10° to 55°, and a tip of the combustion flame injection port that injects the combustion flame is above a virtual horizontal plane passing through an upper end edge of the pulverization cooling cylinder.

11 . A method of producing a metal powder, comprising:
a first pulverizing step of convergently injecting a supersonic combustion flame into a downwardly supplied molten metal and firstly pulverizing the molten metal to form molten droplets; a second pulverizing step of jetting the combustion flame as a focused jet flow including the firstly pulverized droplets directly downward, moving the firstly pulverized droplets in the focused jet flow, which has a relatively fast speed, and secondly pulverizing the droplets to form smaller molten droplets; and a third pulverizing step of thrusting the focused jet flow including the secondly pulverized droplets into a revolving water flow and thirdly pulverizing and cooling the focused jet flow to make a metal powder smaller than the secondly pulverized droplets.

12 . The method of producing a metal powder according to claim 11 , wherein an airflow equally flows into an upstream portion of the focused jet flow from all sides.

Assignees

• Hard Industry Yg
• Hitachi Metals Ltd

Inventors

• Yamagata Torao
• Yamagata Takuichi
• Izaki Hiroshi

Classifications

• B22F1/08

  Metallic powder characterised by particles having an amorphous microstructure · CPC title

• B22F1/065

  Spherical particles · CPC title

• B22F1/05

  Metallic powder characterised by the size or surface area of the particles · CPC title

• B22F9/082 Primary

  atomising using a fluid (using centrifugal force B22F9/10) · CPC title

• B22F2009/0828

  with water · CPC title