Black zirconia sintered body and preparation method therefor and use thereof

Abstract

A black zirconia sintered body is obtained by processing and forming a powder for the black zirconia sintered body, and then sintering the same at a high temperature and normal pressure in the atmosphere. The powder for the black zirconia sintered body is prepared by a hydrothermal synthesis method using a soluble zirconium salt, a soluble yttrium salt and a color former as raw materials, wherein the molar ratio of the soluble zirconium salt, the soluble yttrium salt and the color former is 90-95:1-5:1-9. The black zirconia sintered body can be used in ceramic processes.

Claims

1. A method of forming a powder for a black zirconia sintered body, the method comprising the following steps: S1, mixing a soluble zirconium salt and a soluble yttrium salt at a ratio and dissolving the zirconium salt and the yttrium salt in water to form a slurry, adding a coloring agent, and adjusting the pH of the slurry to 8 to 10 with ammonia water under stirring, wherein the molar ratio of the soluble zirconium salt, the soluble yttrium salt, and the coloring agent is 90 to 95:1 to 5:1 to 9; S2, subjecting the slurry to hydrothermal synthesis at 140 to 200 C. for 10 to 72 hours to form a resultant reaction solution; S3, washing the resultant reaction solution with water and drying to obtain a powder; S4, subjecting the powder to heat treatment at 800 to 1200 C. for 2 to 5 hours, and then grinding and dispersing the powder; and S5, granulating the dispersed particles to obtain the powder for a black zirconia sintered body.

2. The method of claim 1, wherein the zirconia powder has a BET specific surface area of 10 to 16 m.sup.2/g, and an average particle diameter of 0.1 to 0.3 m.

3. The method of claim 1, wherein the coloring agent in step S1 includes at least one selected material chosen from among cobalt oxide, manganese oxide, iron oxide, titanium oxide, aluminum oxide, nickel oxide, copper oxide, erbium oxide, silicon oxide, zinc oxide and chromium oxide.

4. The method of claim 1, further comprising sintering the powder to form a black zirconia sintered body.

5. The method of claim 4, wherein the black zirconia sintered body has an L value of 3, an a value of 1 to 1, a b value of 1 to 1, a ceramic body density of 6.0 g/cm.sup.3, and a three-point flexural strength greater than or equal to 1100 MPa.

6. The method of claim 4, wherein sintering the powder comprises processing and molding the powder to form a green structure, and then subjecting the green structure to high-temperature sintering in an atmosphere at atmospheric pressure.

7. The method of claim 6, wherein the high-temperature sintering is performed at 1400 to 1550 C. for 1 to 4 hours.

8. The method of claim 6, processing and molding the powder to form a green structure comprises compression molding or injection molding the powder to form the green structure.

9. The method of claim 1, wherein the molar ratio of the soluble zirconium salt, the soluble yttrium salt, and the coloring agent is 92:3:5 in step S1.

Description

DETAILED DESCRIPTION

(1) The following Examples are intended to illustrate embodiments of the present disclosure, but are not intended to limit the scope of the present invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, and the raw materials used are all commercially available products.

(2) The percent sign % involved in this disclosure means a percentage by mass unless otherwise specified. However, the percentage of a solution, unless otherwise specified, means the number of grams of the solute contained in 100 mL solution.

EXAMPLES 1 to 5: Powder for Black Zirconia Sintered Body

(3) The powder for black zirconia sintered body was obtained from a soluble zirconium salt, a soluble yttrium salt and a coloring agent as raw materials by hydrothermal synthesis (Table 1).

(4) TABLE-US-00001 TABLE 1 The powder for black zirconia sintered body BET value Average of the diameter resulting of the Molar ratio of raw materials powder, powder, and various components m.sup.2/g m Example 1 zirconium nitrate, yttrium nitrate 12.98 0.20 and coloring agent (iron oxide and/or manganese oxide) with the molar ratio of 94:3:3 Example 2 zirconium nitrate, yttrium nitrate 11.23 0.21 and coloring agent (iron oxide and/or cobalt oxide) with the molar ratio of 91:3.5:5.5 Example 3 zirconium nitrate, yttrium nitrate 13.35 0.18 and coloring agent (iron oxide and/or cobalt oxide and/or copper oxide) with the molar ratio of 93:2:5 Example 4 zirconium nitrate, yttrium nitrate and 15.65 0.15 coloring agent (iron oxide and/or aluminum oxide and/or copper oxide) with the molar ratio of 92:3:5 Example 5 zirconium nitrate, yttrium nitrate and 10.89 0.26 coloring agent (iron oxide and/or manganese oxide and/or copper oxide) with the molar ratio of 91:4:5

(5) The specific process was as follows:

(6) S1, the soluble zirconium salt and the soluble yttrium salt were mixed at a ratio and dissolved in water, the coloring agent was added, ammonia water was added slowly under stirring, and the pH of the slurry was adjusted to 8 to 10 with ammonia water;

(7) S2, the above slurry was transferred to a reaction kettle, and subjected to hydrothermal synthesis at 140 to 200 C. for 10 to 72 hours;

(8) S3, the resultant reaction solution was washed with water and dried to obtain a powder;

(9) S4, the powder was subjected to heat treatment at 800 to 1200 C. for 2 to 5 hours, and then grinding and dispersing; and

(10) S5, the dispersed particles were granulated to obtain the powder for black zirconia sintered body.

EXAMPLES 6 to 10: Black Zirconia Sintered Body and Preparation Method Thereof

(11) The powder obtained in Examples 1 to 5 was subjected to dry compression molding (molding pressure of 150 to 250 MPa), and sintered at 1400 to 1550 C. in the atmosphere under normal pressure for 1 to 4 hours to give a black zirconia sintered body.

(12) The various indexes of the obtained sintered body products were shown in Table 2.

(13) TABLE-US-00002 TABLE 2 Indexes of the black zirconia sintered body products Ceramic Three-point body flexural L a b density, strength, value value value g/cm.sup.3 MPa Example 1 2.3 0.03 0.02 6.001 1337.3 Example 2 2.5 0.01 0.01 5.999 1298.3 Example 3 2.2 0.01 0.03 5.998 1468.9 Example 4 2.3 0.02 0.04 5.999 1489.0 Example 5 2.9 0.03 0.02 6.000 1231.3

(14) The black zirconia sintered body provided in this disclosure can be used in the manufacture of ceramic knives, watch cases, mobile phone cases, abrasive tools, decorations and other structural members.

(15) Although this disclosure is described in detail with general description and specific embodiments as above, it will be apparent to a person skilled in the art that some modifications and improvements can be made. Therefore, such modifications or improvements made without departing from the spirit of this disclosure are intended to be within the scope of this disclosure.

INDUSTRIAL APPLICABILITY

(16) The black zirconia sintered body provided in this disclosure can be used in ceramic process. The black zirconia sintered body can be prepared using the zirconia powder of this disclosure with simple process, and protective atmosphere and hot pressed sintering are not needed during sintering; the sintered body has uniform texture, high strength, and a three-point flexural strength of 1100 MPa; and the sintering is free of pollution.