Fiber-reinforced ceramic matrix composite for electronic devices

• US 10,703,680 B2
• Filed: 05/04/2016
• Issued: 07/07/2020
• Est. Priority Date: 05/25/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Meschke, Andrew J., Matsuyuki, Naoto
• Primary Examiner(s): Steele, Jennifer A
• Application Number:
  US15/146,545
• Publication Number:
  US 20160347674A1
• Time in Patent Office: 1,525 Days
• CPC Class Codes: B28B 1/24 by injection moulding injection moulding of ceramic slips B28B1/265; of tubular articles B28B21/38
• CPC Class Codes: B28B 1/52 specially adapted for producing articles from mixtures containing fibres, e.g. asbestos cementby wrapping on to mandrels B28B1/42
• CPC Class Codes: B28B 7/0008 Venting channels, e.g. to avoid vacuum during demoulding or allowing air to escape during feeding, pressing or moulding
• CPC Class Codes: C04B 2235/3229 Cerium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/5236 Zirconia
• CPC Class Codes: C04B 2235/5248 Carbon, e.g. graphite
• CPC Class Codes: C04B 2235/526 characterised by the length of the fibers
• CPC Class Codes: C04B 2235/5268 Orientation of the fibers
• CPC Class Codes: C04B 2235/60 Aspects relating to the preparation, properties or mechanical treatment of green bodies or pre-forms
• CPC Class Codes: C04B 2235/602 Making the green bodies or pre-forms by moulding
• CPC Class Codes: C04B 2235/6027 Slip casting
• CPC Class Codes: C04B 35/01 based on oxide ceramics
• CPC Class Codes: C04B 35/08 based on beryllium oxide
• CPC Class Codes: C04B 35/10 based on aluminium oxide
• CPC Class Codes: C04B 35/48 based on zirconium or hafnium oxides, zirconates, zircon or hafnates
• CPC Class Codes: C04B 35/50 based on rare-earth compounds non-oxide rare earth compounds C04B35/5156
• CPC Class Codes: C04B 35/515 based on non-oxide ceramics
• CPC Class Codes: C04B 35/56 based on carbides or oxycarbides containing free metal binder C22C29/00
• CPC Class Codes: C04B 35/58 based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides containing free binder metal C22C29/00
• CPC Class Codes: C04B 35/5805 based on borides
• CPC Class Codes: C04B 35/58085 : based on silicides
• CPC Class Codes: C04B 35/638 : Removal thereof
• CPC Class Codes: C04B 35/80 : Fibres, filaments, whiskers, platelets, or the like
• CPC Class Codes: Y10T 428/249928 : Fiber embedded in a ceramic, glass, or carbon matrix

Abstract

A method of forming a ceramic component is disclosed. A ceramic matrix material is combined with a binder material. The ceramic matrix material and the binder material are mixed to create an intermediate slurry. After mixing the ceramic matrix material and the binder material, reinforcing fibers are added to the intermediate slurry to create a final slurry. The final slurry is introduced into a mold cavity having a shape corresponding to the ceramic component. The final slurry is at least partially cured within the mold cavity to form an intermediate casting. The intermediate casting is sintered to produce the ceramic component from the intermediate casting.

Claims

1. A ceramic housing component for an electronic device, comprising:

a unitary sintered ceramic matrix material formed from a slurry deposited into a mold cavity;

reinforcing fibers distributed substantially evenly throughout the ceramic matrix material and aligned in directions of flow of the slurry when the slurry is introduced into the mold cavity, the reinforcing fibers being oriented radially outwardly from a particular area within a first portion of the ceramic housing component and unidirectionally within a second portion of the ceramic housing component, a direction of the reinforcing fibers of the second portion being different from directions of the reinforcing fibers of the first portion;

wherein the ceramic housing component is formed by sintering a slurry comprising the ceramic matrix material and the reinforcing fibers to remove a binder from the ceramic matrix material.

2. The ceramic housing component of claim 1, wherein the ceramic matrix material is selected from the group consisting of porcelain, alumina, beryllia, ceria, zirconia, carbide, boride, nitride, and silicide.

3. The ceramic housing component of claim 1, wherein the reinforcing fibers have an average length of about 150 microns.

4. The ceramic housing component of claim 1, wherein the ceramic matrix material is zirconia powder.

5. The ceramic housing component of claim 1, wherein the reinforcing fibers within the second portion are aligned substantially parallel with a major axis of the ceramic housing component.

6. A housing component for an electronic device, comprising:

a unitary structure comprising a ceramic matrix formed from a slurry including a ceramic matrix material and reinforcing fibers, the unitary structure defining;

a back portion having the reinforcing fibers oriented substantially radially outwardly from a particular area and aligned in directions of flow of the slurry when the slurry is introduced into a mold cavity; and

side portions extending from the back portion and having the reinforcing fibers oriented substantially unidirectionally in a direction aligned in a direction of the flow of the slurry when the slurry is introduced into the mold cavity, the direction different from directions of the reinforcing fibers of the back portion;

wherein the unitary structure is formed by sintering the slurry to remove a binder therefrom.

7. The housing component of claim 6, wherein the direction is perpendicular to the reinforcing fibers of the back portion.

8. The housing component of claim 6, wherein the reinforcing fibers are chopped fibers.

9. The housing component of claim 8, wherein the reinforcing fibers have a length from about 50 microns to about 250 microns.

10. The housing component of claim 6, wherein the reinforcing fibers are carbon fibers encased in silicon carbide sheaths.

11. A ceramic housing component for an electronic device, comprising:

a unitary structure comprising a sintered ceramic matrix material and reinforcing fibers distributed substantially evenly throughout the sintered ceramic matrix material, the unitary structure defining;

a back portion having the reinforcing fibers oriented radially outwardly from a particular area within the back portion; and

a side portion extending from the back portion and having the reinforcing fibers oriented randomly.

12. The ceramic housing component of claim 11, wherein the ceramic matrix material is selected from the group consisting of porcelain, alumina, beryllia, ceria, zirconia, carbide, boride, nitride, and silicide.

13. The ceramic housing component of claim 11, wherein the reinforcing fibers have an average length of about 150 microns.

14. The ceramic housing component of claim 11, wherein the ceramic matrix material is zirconia powder.

15. The ceramic housing component of claim 11, wherein the reinforcing fibers within the back portion are first reinforcing fibers and the reinforcing fibers within the side portion are second reinforcing fibers;

and

the first reinforcing fibers comprise a first material and the second reinforcing fibers comprise a second material that is different from the first material.

16. The ceramic housing component of claim 15, wherein the first reinforcing fibers or the second reinforcing fibers comprise at least one of zirconia or alumina.