Shaped abrasive particles and methods of forming same

• US 9,200,187 B2
• Filed: 05/23/2013
• Issued: 12/01/2015
• Est. Priority Date: 05/23/2012
• Status: Active Grant

• Current Assignee: Saint-Gobain Ceramics & Plastics Incorporated (Compagnie De Saint-Gobain)
• Original Assignee: Saint-Gobain Ceramics & Plastics Incorporated (Compagnie De Saint-Gobain)
• Inventors: Bauer, Ralph, Barnes, Martin, Demers, Rene G., Skowron, Margaret L.
• Primary Examiner(s): KILIMAN, LESZEK B
• Application Number:
  US13/901,362
• Publication Number:
  US 20130337262A1
• Time in Patent Office: 922 Days
• Field of Search: 428/402, 425/382.4, 512/93
• US Class Current: 1/1
• CPC Class Codes: B01J 2/20 by expressing the material, e.g. through sieves and fragmenting the extruded length
• CPC Class Codes: B01J 2/22 by pressing in moulds or between rollers
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/6021 Extrusion moulding
• CPC Class Codes: C04B 35/10 based on aluminium oxide
• CPC Class Codes: C04B 35/624 Sol-gel processing
• CPC Class Codes: C09K 3/1409 Abrasive particles per se preparation of diamond C01B32/25
• CPC Class Codes: C09K 3/1427 obtained by division of a mass agglomerated by melting, at least partially, e.g. with a binder
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

A method of forming a shaped abrasive particle includes applying a mixture into a shaping assembly within an application zone and directing an ejection material at the mixture in the shaping assembly under a predetermined force, removing the mixture from the shaping assembly and forming a precursor shaped abrasive particle.

Claims

1. A system for forming shaped abrasive particles comprising:

an application zone comprising a shaping assembly including;

a first portion having an opening and configured to be filled with a mixture;

a second portion abutting the first portion; and

an ejection zone comprising an ejection assembly configured to direct an ejection material toward the opening in the first portion of the shaping assembly.

2. The system of claim 1, wherein the mixture comprises a gel comprising a ceramic powder material as an integrated network of discrete particles.

3. The system of claim 1, wherein the mixture comprises not greater than 30 wt % organic materials for the total weight of the mixture.

4. The system of claim 1, wherein the mixture comprises a storage modulus of at least 1×

10⁴ Pa.

5. The system of claim 1, wherein the mixture comprises a viscosity of at least 4×

10³ Pa s.

6. The system of claim 1, wherein the shaping assembly comprises an opening configured to receive the mixture and defined by at least three surfaces.

7. The system of claim 1, wherein the first portion comprises a screen and the second portion comprises a backing plate, wherein the first portion and the second portion are adjacent to each other in the application zone.

8. The system of claim 7, wherein a surface of the backing plate is configured to contact the mixture in the opening of the screen.

9. The system of claim 1, wherein at least a portion of the shaping assembly is translated through the application zone.

10. The system of claim 1, further comprising an extruder configured to extrude the mixture through a die opening and into an opening in the shaping assembly.

11. The system of claim 1, further comprising a translator configured to translate at least a portion of the shaping assembly from the application zone to the ejection zone.

12. The system of claim 1, wherein the mixture comprises a change in weight of less than 5% for a total weight of the mixture for a duration the mixture is in an opening of the shaping assembly.

13. The system of claim 1, wherein the mixture comprises a change in volume of less than 5% for a total volume of the mixture for a duration the mixture is in an opening of the shaping assembly.

14. The system of claim 1, wherein an average residence time of the mixture in an opening of the shaping assembly is less than 18 minutes.

15. The system of claim 1, wherein an average residence time of the mixture in an opening of the shaping assembly is less than 20 seconds.

16. The system of claim 1, wherein the ejection material is directed at the mixture in the shaping assembly under a predetermined force of at least 0.1 N.

17. The system of claim 1, wherein the ejection material comprises a fluidized material comprises a liquid, a gas, and a combination thereof.

18. The system of claim 1, wherein the ejection material is configured to be directed at the mixture at a temperature of not greater than 300°

C.

19. The system of claim 1, wherein the mixture comprises a coil value of at least 1800 N.

20. The system of claim 1, wherein the application zone and the ejection zone are configured to be operated at a temperature differential of not greater than 10°

C.