Laser ablation method for treating a zirconia containing ceramic surface

Patent metadata

Field	Value
Publication number	US-9708225-B2
Application number	US-201514943842-A
Country	US
Kind code	B2
Filing date	Nov 17, 2015
Priority date	Nov 17, 2015
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A method of treating a ceramic surface containing zirconia, whereby the ceramic surface is ablated by directing a laser beam with a diameter of 200-400 μm produced by a CO 2 laser with a pulse frequency of 1200-1800 Hz onto the ceramic surface, and a N 2 assist gas is concurrently applied with a pressure of 550-650 KPa co-axially with the laser beam to form an ablated ceramic surface comprising microgrooves with ZrN present on a surface of the microgrooves, wherein the ablated ceramic surface has a higher surface hydrophobicity than the ceramic surface prior to the ablating.

First claim

The invention claimed is:

1. A method of treating a ceramic surface comprising zirconia, the method comprising:
ablating the ceramic surface by directing a laser beam with a diameter of 200-400 μm produced by a CO 2 laser with a pulse frequency of 1200-1800 Hz onto the ceramic surface; and
concurrently exposing the ceramic surface to a N 2 assist gas with a pressure of 550-650 KPa to form an ablated ceramic surface comprising microgrooves with ZrN present on a surface of the microgrooves, wherein the N 2 assist gas and the laser beam are oriented co-axially;
wherein the ceramic surface is not pretreated with particles selected from the group consisting of TiC and B 4 C prior to the ablating;
wherein the ablated ceramic surface has a Vickers hardness of 19.2-23 GPa; and
wherein the ablated ceramic surface has a higher surface hydrophobicity than the ceramic surface prior to the ablating.

2. The method of claim 1 , wherein the ceramic surface comprises yttria stabilized zirconia.

3. The method of claim 1 , wherein the ceramic surface is ablated with a laser beam having a power ranging from 1.5-2.5 kW.

4. The method of claim 1 , wherein the ceramic surface is ablated with a laser beam with a scanning speed ranging from 7-13 cm·s −1 .

5. The method of claim 1 , wherein the ceramic surface is ablated with a laser beam penetration depth of 3-8 μm.

6. The method of claim 1 , wherein the ablated ceramic surface has a surface roughness ranging from 0.25-0.35 μm when measured on a 1 μm×1 μm area.

7. The method of claim 1 , wherein the microgrooves have an average width of 40-60 μm and an average distance between the microgrooves is 20-30 μm.

8. The method of claim 1 , wherein the ablated ceramic surface has a surface energy of 40-55 mJ/m 2 .

9. The method of claim 1 , wherein the ablated ceramic surface has an average water droplet contact angle of 98-121.4°.

10. The method of claim 1 , which increases the surface hydrophobicity of the ceramic surface by at least 100% relative to a ceramic surface that is not treated by the ablating and the concurrently exposing as measured by an average water droplet contact angle.

11. The method of claim 1 , wherein the ablated ceramic surface has an average glycerol droplet contact angle of 93-120°.

12. The method of claim 1 , wherein the ablated ceramic surface has an average diiodomethane droplet contact angle of 35-45°.

13. The method of claim 1 , wherein the ablated ceramic surface has a Vickers hardness of 19.2 GPa.

14. The method of claim 1 , wherein the ablated ceramic surface has a residual stress of −1.7 to −1.5 GPa.

15. The method of claim 1 , wherein the ablated ceramic surface has a fracture toughness of 6.5-9.0 MPa·√m.

16. The method of claim 1 , wherein the ceramic surface is not pretreated with a film, a resin, nanostructures, or any combination thereof prior to the ablating.

17. The method of claim 1 , further comprising coating the ablated ceramic surface with a hydrophobic layer to form a superhydrophobic ceramic surface.

18. The method of claim 17 , wherein the hydrophobic layer comprises at least one selected from the group consisting of a fluorocarbon, a perfluorocarbon, a resin, a hydrophobic fatty acid, and a hydrophobic self-assembled monolayer.

19. A method of treating a yttria stabilized zirconia surface, comprising:
ablating the yttria stabilized zirconia surface by directing a laser beam produced by a laser with a pulse frequency of 1200-1800 Hz onto the yttria stabilized zirconia surface; and
concurrently exposing the yttria stabilized zirconia surface to a N 2 assist gas with a pressure of 550-650 KPa to form an ablated yttria stabilized zirconia surface comprising microgrooves with ZrN present on a surface of the microgrooves, wherein the N 2 assist gas and the laser beam are oriented co-axially;
wherein the yttria stabilized zirconia surface is not pretreated with particles selected from the group consisting of TiC and B 4 C prior to the ablating;
wherein the ablated yttria stabilized zirconia surface has a surface hydrophobicity that is at least 100% higher than a yttria stabilized zirconia surface that is not treated by the ablating and the concurrently exposing as measured by an average water droplet contact angle; and
wherein the ablated yttria stabilized zirconia surface has a Vickers hardness of 19.2-23 GPa.

20. A method of treating a yttria stabilized zirconia surface, comprising:
ablating the yttria stabilized zirconia surface by directing a laser beam produced by a CO 2 laser with a pulse frequency of 1200-1800 Hz onto the yttria stabilized zirconia surface; and
concurrently exposing the yttria stabilized zirconia surface to a N 2 assist gas with a pressure of 550-650 KPa to form an ablated yttria stabilized zirconia surface comprising microgrooves with ZrN present on a surface of the microgrooves, wherein the N 2 assist gas and the laser beam are oriented co-axially;
wherein the ablated yttria stabilized zirconia surface has a Vickers hardness of 19.2-23 GPa;
wherein the ablated yttria stabilized zirconia surface has a higher surface hydrophobicity than the yttria stabilized zirconia surface; and
wherein the yttria stabilized zirconia is not pretreated with particles selected from the group consisting of TiC and B 4 C, a film, a resin, nanostructures, or any combination thereof prior to the ablating.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Yilbas Bekir Sami
• Ali Haider

Classifications

• B23K26/14

  using a fluid stream, e.g. a jet of gas, in conjunction with the laser beam; Nozzles therefor (B23K26/12 takes precedence) · CPC title

• C04B2235/3246

  Stabilised zirconias, e.g. YSZ or cerium stabilised zirconia · CPC title

• C04B41/4556

  coating or impregnating with a product reacting with the substrate, e.g. generating a metal coating by surface reduction of a ceramic substrate · CPC title

• C04B2237/52

  Pre-treatment of the joining surfaces, e.g. cleaning, machining · CPC title

• B28B11/04

  for coating {or applying engobing layers}(glazing, engobing C04B) · CPC title