Process for producing zirconia-based multi-phasic ceramic composites

Patent metadata

Field	Value
Publication number	US-10093583-B2
Application number	US-201515119717-A
Country	US
Kind code	B2
Filing date	Feb 13, 2015
Priority date	Feb 21, 2014
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

A process is described, for producing zirconia-based multi-phasic ceramic composite materials, comprising the steps of: providing at least one ceramic suspension by dispersing at least one ceramic zirconia powder in at least one aqueous medium to obtain at least one matrix for such composite material; providing at least one aqueous solution containing one or more inorganic precursors and adding such aqueous solution to such ceramic suspension to surface modify such ceramic zirconia powder and obtain at least one additived suspension; quickly drying such additived suspension to obtain at least one additived powder; heat treating such additived powder to obtain at least one zirconia powder coated on its surface by second phases; and forming such zirconia powder coated on its surface by second phases.

First claim

The invention claimed is:

1. A process for producing a zirconia-based multi-phasic ceramic composite material, the process comprising the steps of:
a) providing at least one ceramic suspension by dispersing at least one ceramic zirconia powder in at least one aqueous medium to obtain at least one ceramic suspension;
b) providing at least one aqueous solution containing one or more inorganic precursors and adding the aqueous solution to the ceramic suspension to surface modify the ceramic zirconia powder, thereby forming a surface modified ceramic zirconia powder;
c) drying the surface modified ceramic zirconia powder to obtain an additive powder; through nebulization of the surface modified ceramic zirconia powder to an aerosol of micro-drops at a temperature between 80° C. and 200° C.; and
d) heat treating the additive powder to obtain at least one zirconia powder coated on its surface by second phases thereby producing the zirconia-based multi-phasic ceramic composite material.

2. The process according to claim 1 , wherein the ceramic zirconia powder is stabilized by an oxide, the oxide comprising cerium oxide or yttrium oxide.

3. The process according to claim 2 , wherein the molar ratio of cerium oxide to ceramic zirconia powder is between 5% and 15%.

4. The process according to claim 1 , wherein the aqueous medium is deionized water and the ceramic zirconia powder is dispersed in the deionized water with a powder to water weight ratio between 1:1 and 1:20.

5. The process according to claim 1 , wherein step a) further comprises i) dispersing an aqueous medium-ceramic powder suspension through at least one ball milling machine, with a powder to balls weight ratio between 1:1 and 1:20, for between 1 and 50 hours, and ii) setting and maintaining a constant pH in the ceramic suspension during step a).

6. The process according to claim 1 , wherein the inorganic precursors comprise one or more cerium, yttrium, aluminum, magnesium, strontium, lanthanum or manganese salts.

7. The process according to claim 1 , wherein step b) further comprises i) adding the aqueous solution dropwise to the ceramic suspension while stirring the ceramic suspension, and ii) measuring a pH value of the ceramic suspension.

8. The process according to claim 1 , wherein step d) further comprises i) heating the additive powder at a temperature between 200° C. and 800° C. for between 1 and 20 hours, and with a cooling and heating rate between 1 and 20° C./min, and ii) heating the heated additive powder at a temperature between 500° C. and 1300° C. for between 1 and 20 hours, and with a cooling and heating rate between 1 and 20° C./min.

9. The process according to claim 1 , further comprising step e), step e) comprising naturally sinterizing the zirconia-based multi-phasic ceramic composite material, namely, sinterizing the zirconia-based multi-phasic ceramic composite material in air and at atmospheric pressure.

10. The process of claim 2 , wherein the oxide comprises two or more stabilizers.

11. The process according to claim 2 , wherein the molar ratio of yttrium oxide to ceramic zirconia powder is between 1% and 10%.

Assignees

• Torino Politecnico
• Inst Nat Sciences Appliquees Lyon
• Doceram Medical Ceram Gmbh
• Univ Claude Bernard Lyon
• Centre Nat Rech Scient
• Decoram Medical Ceram Cmbh

Inventors

• Montanaro Laura
• Palmero Paola
• Chevalier Jerome
• Reveron Helen
• Fuerderer Tobias

Classifications

• C04B2235/443

  Nitrates or nitrites · CPC title

• C04B2235/3227

  Lanthanum oxide or oxide-forming salts thereof · CPC title

• C04B2235/785

  Submicron sized grains, i.e. from 0,1 to 1 micron · CPC title

• C04B2235/80

  Phases present in the sintered or melt-cast ceramic products other than the main phase · CPC title

• C04B35/62886

  by wet chemical techniques · CPC title