Claims
- 1. A method for preparing a sintered zirconia body in sheet form, comprising the step of firing a green sheet of zirconia having a thickness of less than 1 mm and a surface area of more than 10 cm by 10 cm while placing at least one weight on said green sheet to apply a load thereto, wherein said weight having a weight per unit area W (g/cm.sup.2) and a surface area S (cm.sup.2) is placed on said green sheet to apply a load per unit area G (g/cm.sup.2) to said green sheet so as to satisfy the following conditions
- S.ltoreq.200, about 1.01.ltoreq.G.ltoreq.5, and 1.gtoreq.W/G.gtoreq.0.5,
- thereby producing a sintered zirconia body in sheet form having a thickness of 0.01 to 0.5 mm and a length to thickness ratio of 500 to 5,000.
- 2. The method of claim 1, wherein said weight is made of a porous material having a porosity of 5 to 30%.
- 3. The method of claim 1, wherein said green sheet of zirconia is prepared from zirconia powder which has been partially or fully stabilized by adding a stabilizer element thereto.
- 4. The method of claim 3, wherein said stabilizer element is a member selected from the group consisting of yttrium, calcium, magnesium, and a lanthanide.
- 5. The method of claim 4, wherein said lanthanide is a member selected from the group consisting of ytterbium and cerium.
- 6. The method of claim 4, wherein said stabilizer element is a member selected from the group consisting of yttrium and ytterbium.
- 7. The method of claim 1, wherein said sintered zirconia body in sheet form has a thickness of up to 0.3 mm and a thickness ratio of at least 1,000.
- 8. The method of claim 1, wherein S.ltoreq.150, G.ltoreq.5, and W/G.gtoreq.0.7.
- 9. The method of claim 1, wherein said weight is porous alumina.
- 10. The-method of claim 2, wherein said weight is made of a porous material having a porosity of 10 to 20%.
- 11. The method of claim 1, wherein said firing is conducted at a temperature of 1,300.degree. to 1,600.degree. C. for about 10 minutes to about 10 hours at a heating rate of about 5.degree. C. per minute or less.
- 12. The method of claim 1, wherein said firing is conducted at a temperature of 1,350.degree. to 1,500.degree. C. for about 10 minutes to about 10 hours at a heating rate of about 5.degree. C. per minute or less.
- 13. The method of claim 11, wherein said firing is conducted for about 1 to 4 hours.
- 14. The method of claim 12, wherein said firing is conducted for about 1 to 4 hours.
- 15. The method of claim 11, wherein said heating rate during firing shrinkage is in the range from up to 0.5.degree. C. per minute to up to 1.5.degree. C. per minute.
- 16. The method of claim 12, wherein said heating rate during firing shrinkage is in the range from up to 0.5.degree. C. per minute to up to 1.5.degree. C. per minute.
- 17. The method of claim 1, wherein said green sheet rests on a setter having a thickness of at least 5 mm.
- 18. A method for preparing a sintered zirconia body in sheet form, comprising the step of firing a green sheet of zirconia having a thickness of less than 1 mm and a surface area of at least 15 cm by 15 cm while placing a plurality of weights on said green sheet to apply a load thereto, wherein said weights having a weight per unit area W (g/cm.sup.2) and a surface area S (cm.sup.2) are placed on said green sheet to apply a load per unit area G (g/cm.sup.2) to said green sheet so as to satisfy the following conditions:
- S.ltoreq.200, about 1.01.ltoreq.G.ltoreq.5, and 1.gtoreq.W/G.gtoreq.0.5,
- thereby producing a sintered zirconia body in sheet form having a thickness of 0.01 to 0.5 mm and a length to thickness ratio of 500 to 5,000.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4-067065 |
Mar 1992 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 08/035,404 filed on Mar. 23, 1993, now abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (5)
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0043955 |
Jun 1981 |
EPX |
0237198 |
Feb 1987 |
EPX |
0243858 |
Apr 1987 |
EPX |
3088776 |
Apr 1991 |
JPX |
3141164 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
35404 |
Mar 1993 |
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