Arc apparatus for producing ultrafine particles

• US 4,732,369 A
• Filed: 08/21/1986
• Issued: 03/22/1988
• Est. Priority Date: 10/30/1985
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Endo, Yoshishige, Ibaraki, Yoshiro, Kanamaru, Masatoshi, Araya, Takeshi, Hioki, Susumu
• Primary Examiner(s): Rutledge, L. Dewayne
• Assistant Examiner(s): McDowell, Robert L.
• Application Number:
  US06/898,600
• Time in Patent Office: 579 Days
• Field of Search: 266/200, 266/207, 75/0.5 C, 264/10, 425/6, 373/60, 373/67, 373/68, 373/69, 373/70, 373/90
• US Class Current: 266/207
• CPC Class Codes: B22F 9/14 using electric discharge
• CPC Class Codes: C04B 35/626 Preparing or treating the powders individually or as batches pigments for ceramics C09C1/0009; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B

Abstract

An apparatus for producing ultrafine particles by arc energy characterized by disposing an electrode inclinedly as to a base material so as to generate a magnetic blow to arc, disposing a suction opening at the direction of the arc blown, and cooling vapors generated, followed by collection thereof can improve the production efficiency of ultrafine particles with a uniform particle size.

Claims

1. An apparatus for producing ultrafine particles of metals, alloys or ceramics by using arc energy comprising a generating chamber for generating ultrafine particles of metals, alloys or ceramics, an electrode positioned opposite to a base material for producing ultrafine particles so as to generate an electric arc, a suction opening for sucking the ultrafine particles generated in the generating chamber, a trap for collecting the ultrafine particles sucked from the suction opening, and a cooler positioned between the suction opening and the trap for cooling the sucked ultrafine particles, characterized in that

the electrode is disposed inclinedly as to the base material so as to produce magnetic blow to the arc,

the suction opening is positioned at the direction of the arc blown, and

a cooling-gas feeder is positioned near the arc.

2. An apparatus according to claim 1, wherein the cooling-gas feeder is positioned around the arc.

3. An apparatus according to claim 1, wherein the cooling-gas feeder is positioned between the arc and the suction opening.

4. An apparatus according to claim 2, wherein the electrode is inclined at an angle of 10°

to 50°

regarding a horizontal line of base material.

5. An apparatus according to claim 2, wherein a pulse current of 50 Hz to 20 kHz is used as an arc current.

6. An apparatus according to claim 2, wherein a heat source for revaporizing the ultrafine particles is placed between the suction opening and the cooler.

7. An apparatus according to claim 3, wherein the electrode is inclined at an angle of 10°

to 50°

regarding a horizontal line of base material.

8. An apparatus according to claim 3, wherein a pulse current of 50 Hz to 20 kHz is used as an arc current.

9. An apparatus according to claim 3, wherein a heat source for revaporizing the ultrafine particles is placed between the suction opening and the cooler.

10. An apparatus for producing ultrafine particles of metals, alloys or cermics by using arc energy comprising a generating chamber for generating ultrafine particles of metals, alloys or ceramics, at least one electrode positioned opposite to a base material for producing ultrafine particles so as to generate an electric arc, a suction opening for sucking the ultrafine particles generated in the generating chamber, a trap for collecting the ultrafine particles sucked from the suction opening, and a cooler positioned between the suction opening and the trap for cooling the sucked ultrafine particles, characterized in that:

the at least one electrode includes an electrode for generating a plasma arc and disposed inclinedly as to the base material so as to produce magnetic blow to the arc, and another arc discharge electrode disposed opposite to the base material so as to generate a gas tungsten arc in addition to the electrode for generating a plasma arc; and

the suction opening is positioned at the direction of the arc blown.

11. An apparatus according to claim 10, wherein the arc is generated between the electrode for generating a plasma arc and the electrode for generating a gas tungsten arc.

12. An apparatus according to claim 10, wherein the arc is generated between the electrode for generating a plasma arc and the electrode for generating a gas tungsten arc, and between the electrode for generating a plasma arc and the base material.

14. An apparatus according to claim 10, wherein the electrode for generating a gas tungsten arc is disposed at a vertical position within the generating chamber.

13. An apparatus for producing ultrafine particles of metals, alloys or ceramics by using arc energy comprising a generating chamber for generating ultrafine particles of metals, alloys or ceramics, an electrode positioned opposite to a base material for producing ultrafine particles so as to generate an electric arc, a suction opening for sucking the ultrafine particles generated in the generating chamber, a trap for collecting the ultrafine particles sucked from the suction opening, and a cooler positioned between the suction opening and the trap for cooling the sucked ultrafine particles, characterized in that

the electrode is disposed inclinedly as to the base material so as to produce magnetic blow to the arc,

the suction opening is positioned at the direction of the arc blown so as to suck a generated vapor, and

the base material is obtained by melting a raw material in a gas atmosphere containing oxygen or by adding an element for increasing surface tension of a molten metal according to an increase of metal temperature.