Method of producing a powder product

Patent metadata

Field	Value
Publication number	US-11224916-B2
Application number	US-201916585681-A
Country	US
Kind code	B2
Filing date	Sep 27, 2019
Priority date	Jun 16, 2014
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A method of producing a powder suitable for additive manufacturing and/or powder metallurgy applications from a precursor particulate material comprising: subjecting the precursor particulate material to at least one high shear milling process, thereby producing a powder product having a reduced average particle size and a selected particle morphology.

First claim

The invention claimed is:

1. A method of producing an additive manufacturing and/or powder metallurgy powder from a metal or a metal alloy precursor particulate material comprising irregularly shaped particulate material, said method comprising:
subjecting the metal or a metal alloy precursor particulate material to at least one high shear milling process comprising milling the material with at least one high shear mixer that includes a rotor configured to contact and comminute the precursor particulate material and a stator that extends substantially around the rotor, the stator being configured to have less than 1 mm gap between the rotor and an inner surface of the stator,
thereby producing a metal or a metal alloy powder product having a reduced average particle size relative to the average particle size of the precursor particulate material and a particle morphology consisting essentially of spherically shaped particles.

2. A method according to claim 1 , wherein the powder product has a particle size range determined by powder sieve analysis in which at least 90%, of the particles have an average particle size <300 μm.

3. A method according to claim 1 , wherein the morphology of the powder product can be controlled by changing the shear milling process conditions including at least one of shear milling rotor speed; shear milling time; or amount of precursor powder.

4. A method according to claim 1 , wherein the powder product has at least one of: high flowability of 23 to 35 seconds/20 cm 3 determined following ASTM B855-06; and low contamination of less than 1%.

5. A method according to claim 1 , wherein the flowability of the powder product determined following ASTM B855-06 is between 20 and 23 seconds/20 cm 3 .

6. A method according to claim 1 , wherein the apparent/tap density of the powder product is improved at least by 100% after high shear milling.

7. A method according to claim 1 , wherein the precursor particulate material comprises a coarse particulate material.

8. A method according to claim 1 , wherein the precursor particulate material comprises Ti or Ti alloy particulate material.

9. A method according to claim 1 , wherein the precursor particulate material is subjected to at least one pre-processing step comprising at least one comminution processes.

10. A method according to claim 1 , wherein in the high shear milling process, the precursor particulate material is immersed in a liquid.

11. A method according to claim 10 , wherein the liquid comprises at least one of water, alcohol or kerosene.

12. A method according to claim 1 , wherein the rotor has a rotor diameter, and wherein the precursor particulate material comprises particles having an average particle size of less than the rotor diameter.

13. A method according to claim 1 , wherein the at least one high shear mixer has a circumferential milling speed of at least 700 m/min.

14. A method according to claim 1 , wherein the precursor particulate material comprises porous Ti/Ti alloy particulates and high shear milling is conducted for a duration of at least 15 minutes to produce maximum amount of powder product in the 45-106 μm particle size range.

15. A method according to claim 1 , wherein the stator is configured to have less than 0.8 mm gap between the rotor and the inner surface of the stator.

16. A method according to claim 1 , wherein the stator is configured to have from 0.2 and 0.8 mm gap between the rotor and the inner surface of the stator.

17. A method according to claim 1 , wherein the precursor particulate material is subjected to milling with at least two high shear mills.

Assignees

• Commw Scient Ind Res Org

Inventors

• Oh Chull Hee
• Gulizia Stefan

Classifications

• B22F1/00

  Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties · CPC title

• Y02P10/25

  Process efficiency · CPC title

• B33Y70/00

  Materials specially adapted for additive manufacturing · CPC title

• B02C18/062

  with rotor elements extending axially in close radial proximity of a concentrically arranged slotted or perforated ring · CPC title

• C22C14/00

  Alloys based on titanium · CPC title