Titanium part having an etched surface

Patent metadata

Field	Value
Publication number	US-11511519-B2
Application number	US-202016867200-A
Country	US
Kind code	B2
Filing date	May 5, 2020
Priority date	Jul 8, 2019
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

This application relates to a part for a portable electronic device. The part includes a titanium alloy substrate including a network of branching channels. The branching channels include a first channel and a second channel, where the first channel is defined by a first channel wall that extends away from a first opening in the exterior surface, and the second channel is defined by a second channel wall that extends away from a second opening in the first channel wall.

First claim

What is claimed is:

1. A titanium alloy substrate for a portable electronic device, the titanium alloy substrate comprising:
an exterior surface; and
a branching channel structure that includes a first channel and a second channel, wherein:
the first channel is defined by a first channel wall that extends away from a first opening in the exterior surface, and
the second channel is defined by a second channel wall that extends away from a second opening in the first channel wall.

2. The titanium alloy substrate of claim 1 , wherein the first and second channel walls define, in part, an internal volume.

3. The titanium alloy substrate of claim 1 , wherein the branching channel structure further includes a third channel, and the third channel is defined by a third channel wall that extends from a third opening in the exterior surface.

4. The titanium alloy substrate of claim 3 , wherein the third channel wall further extends from a fourth opening in the first channel wall.

5. The titanium alloy substrate of claim 1 , wherein the first channel extends towards a first terminus surface, and the second channel extends towards a second terminus surface, and the first and second terminus surfaces are positioned at varied depths relative to the exterior surface.

6. The titanium alloy substrate of claim 5 , wherein the varied depths of the first and second terminus surfaces are between 10 micrometers to 20 micrometers from the exterior surface.

7. The titanium alloy substrate of claim 1 , wherein the titanium alloy substrate includes a two-phase titanium alloy having an α-phase and a β-phase, and the first and second channels correspond to preferential etched portions of the β-phase.

8. The titanium alloy substrate of claim 1 , wherein a first portion of the titanium alloy substrate corresponding to the first channel has a first thickness, and a second portion of the titanium alloy substrate corresponding to the second channel has a second thickness different than the first thickness.

9. An enclosure for a portable electronic device, the enclosure comprising:
a first portion including a metal substrate, the metal substrate including an interconnected network of channels, wherein the channels include:
a first channel defined by a first channel wall, wherein the first channel wall extends from a first opening in an external surface of the metal substrate and terminates at a first terminus surface within the metal substrate, and
a second channel defined by a second channel wall, wherein the second channel wall extends between a second opening in the external surface of the metal substrate and a third opening in the first channel wall; and
a second portion including protruding features that extend through the first and second openings and into the first and second channels.

10. The enclosure of claim 9 , wherein the first and second openings are randomly distributed throughout the external surface.

11. The enclosure of claim 9 , wherein the first and second channel walls include multi-angle side surfaces that define a serpentine path.

12. The enclosure of claim 9 , wherein the metal substrate is a two-phase titanium alloy having an α-phase and a β-phase, and the first and second channels correspond to preferential etched portions of the β-phase.

13. The enclosure of claim 9 , wherein the first and second openings have an average diameter between 2 micrometers to 5 micrometers.

14. The enclosure of claim 9 , wherein the second portion includes a polymeric material.

15. The enclosure of claim 9 , wherein a first region of the metal substrate corresponding to the first channel has a first thickness, and a second region of the metal substrate corresponding to the second channel has a second thickness different than the first thickness.

16. A method for forming a part for a portable electronic device, the part including a titanium alloy substrate, the method comprising:
exposing an exterior surface of the titanium alloy substrate to an electrochemical etching process, wherein the electrochemical etching process forms (i) an opening in the exterior surface and a first channel defined by a first channel wall that extends from the opening, and (ii) an opening in the first channel wall and a second channel defined by a second channel wall that extends from the opening in the first channel wall.

17. The method of claim 16 , wherein at least a portion of the second channel is formed concurrently while forming the first channel.

18. The method of claim 17 , further comprising:
adhering a non-metal portion to the titanium alloy substrate.

19. The method of claim 18 , wherein the non-metal portion includes protruding features that extend through the opening in the exterior surface and the opening in the first channel wall.

20. The method of claim 19 , wherein the electrochemical etching process includes immersing the titanium alloy substrate in a chloride-based etching solution.

Assignees

• Apple Inc

Inventors

• Curran James A
• Mintz Todd S
• Yang Isabel

Classifications

• B32B3/30

  characterised by a layer formed with recesses or projections, e.g. {hollows, grooves, protuberances, ribs (apertured layer B32B3/266; layer with cavities or internal voids B32B3/26)} · CPC title

• B32B15/08 Primary

  of synthetic resin · CPC title

• C22C14/00

  Alloys based on titanium · CPC title

• C25F3/04 Primary

  of light metals · CPC title