Solidification method of ceramic powder and solidified ceramics

• US 8,480,801 B2
• Filed: 02/26/2009
• Issued: 07/09/2013
• Est. Priority Date: 02/27/2008
• Status: Active Grant

• Current Assignee: Nagoya Institute of Technology
• Original Assignee: Nagoya Institute of Technology
• Inventors: Fuji, Masayoshi, Yamakawa, Tomohiro, Takahashi, Minoru
• Primary Examiner(s): MARCANTONI, PAUL D
• Application Number:
  US12/918,890
• Publication Number:
  US 20110053761A1
• Time in Patent Office: 1,594 Days
• Field of Search: 106/600, 106/716, 106/718, 501/145, 501/146, 501/147, 241/14
• US Class Current: 106/600
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C04B 14/38 Fibrous materials; Whiskers
• CPC Class Codes: C04B 16/0691 Polyamides; Polyaramides
• CPC Class Codes: C04B 2235/526 characterised by the length of the fibers
• CPC Class Codes: C04B 2235/5264 characterised by the diameter of the fibers
• CPC Class Codes: C04B 2235/5288 Carbon nanotubes
• CPC Class Codes: C04B 2235/5296 with a defined aspect ratio, e.g. indicating sphericity spherical constituents C04B2235/528
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/96 Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• CPC Class Codes: C04B 28/26 Silicates of the alkali metals
• CPC Class Codes: C04B 33/04 Clay; Kaolin
• CPC Class Codes: C04B 33/36 Reinforced clay-wares
• CPC Class Codes: C04B 35/6261 Milling

Abstract

[Object] Providing a solidified ceramic body with an improved mechanical strength, wherein the solidified ceramic body is fabricated by activating ceramic powder through mechanochemical treatment and solidifying the activated ceramic powder through alkali treatment.

[Method of Solution] Activated ceramic powder having mechanochemically amorphized surfaces is obtained by grinding ceramic powder which is composed of silicic acid and/or silicate at least at surfaces thereof (grinding process). Inorganic fibers and/or plastic fibers are added to the activated ceramic powder and are mixed with the activated ceramic powder (mixing process), and a solidified ceramic body is obtained by adding alkali water solution containing alkaline metal hydroxide and/or alkaline earth metal hydroxide to the powder (alkali treatment process).

Claims

1. A solidification method of ceramic powder, comprising:

grinding ceramic powder which is composed of silicic acid and/or silicate at least at surfaces thereof to obtain activated ceramic powder having mechanochemically amorphized surfaces;

adding inorganic fibers and/or organic fibers to the activated ceramic powder and mixing the inorganic fibers and/or organic fibers with the activated ceramic powder to obtain a fiber-activated ceramic powder mixture; and

adding alkali water solution containing alkali metal hydroxide and/or alkaline earth metal hydroxide to the fiber-activated ceramic powder mixture and thereby dissolving and reprecipitating surfaces of the activated ceramic powder to obtain a solidified ceramic body.

2. The solidification method according to claim 1, wherein the ceramic powder serving as raw material is composed of clay mineral and/or quartz.

3. The solidification method according to claim 2, wherein the clay mineral is metakaolin.

4. The solidification method according to claim 1, wherein the organic fibers are made of aromatic polyamide resin.

7. The solidification method according to claim 2, wherein the organic fibers are made of aromatic polyamide resin.

8. The solidification method according to claim 3, wherein the organic fibers are made of aromatic polyamide resin.

5. A solidified ceramic body, the body being solidified by treating a fiber-activated ceramic powder mixture with alkali water solution containing alkali metal hydroxide and/or alkaline earth metal hydroxide,

wherein

the fiber-activated ceramic powder mixture is obtained by adding inorganic fibers and/or organic fibers to activated ceramic powder, and

the activated ceramic powder is obtained by mechanochemically amorphizing ceramic powder which is composed of silicic acid and/or silicate at least at surfaces of the ceramic powder.

6. The solidified ceramic body according to claim 5, wherein

the activated ceramic powder has noncrystalline layers which are obtained by amorphizing the surfaces of ceramic powder through mechanochemical phenomena,

the ceramic powder is solidified by means of precipitated layers which are obtained by dehydrating and condensing the noncrystalline layers dissolved in the alkali water solution, and

the inorganic fibers and/or organic fibers are included in the precipitated layers to constitute a complex.

9. A solidification method of ceramic powder, comprising:

grinding ceramic powder which is composed of silicic acid and/or silicate at least at surfaces thereof to cause mechanochemical phenomena to obtain activated ceramic powder having mechanochemically amorphized surfaces;

adding inorganic fibers and/or organic fibers to the activated ceramic powder and mixing the inorganic fibers and/or organic fibers with the activated ceramic powder to obtain a fiber-activated ceramic powder mixture; and

adding an alkali water solution containing alkali metal hydroxide and/or alkaline earth metal hydroxide to the fiber-activated ceramic powder mixture, thereby dissolving and reprecipitating surfaces of the activated ceramic powder, thereby forming precipitated layers including the inorganic fibers and/or organic fibers, solidifying the ceramic powder by means of the precipitated layers, and thereby obtaining a solidified ceramic body.

10. The solidification method according to claim 9, wherein the ceramic powder is solidified only by means of the precipitated layers.

11. The solidification method according to claim 9, wherein the ceramic powder serving as raw material is composed of clay mineral and/or quartz.

12. The solidification method according to claim 11, wherein the clay mineral is metakaolin.

13. The solidification method according to claim 9, wherein the organic fibers are made of aromatic polyamide resin.