METHOD FOR SINTERING CERAMIC MATERIALS

Abstract

A method for producing a densified component and an article comprising a densified component is disclosed. In a method for producing a densified component, a starting material is subjected to an electric field at a temperature (T) below 800° C. The starting material comprises a first material from the group consisting of cuprates. The method has a low technical effort, since densification is possible without heating the starting material.

Claims

1. A method for producing a densified component, namely a ceramic superconductor, in which a starting material comprising a first material from the group consisting of cuprates is subjected to an electric field at a temperature (T) below 100° C., wherein the starting material has a mass fraction of the first material from the group consisting of cuprates between 50% and 100%.

2. The method according to claim 1, wherein the temperature (T) is less than 50° C.

3. The method according to claim 1, wherein the starting material is subjected to the electric field for a period of time (t) of less than 10 min.

4. The method according to claim 1, wherein the starting material is subjected to the electric field under atmospheric pressure (P).

5. The method according to claim 1, wherein the electric field has an electric field strength greater than 50 V/cm.

6. The method according to claim 1, wherein the starting material comprises a mass fraction between 0% and 50% of a second material.

7. The method according to claim 6, wherein the second material is an electrically insulating material, wherein the electrically insulating material is a ceramic material such as aluminium oxide.

8. The method according to claim 7, wherein at least one first region, in particular at least one first layer, of the starting material consists essentially of the first material and at least one second region, in particular at least one second layer, of the starting material consists essentially of the second material.

9. The method according to claim 6, wherein at least one third region of the starting material comprises a preferably substantially homogeneous mixture of the first material and the second material.

10. The method according to claim 1, wherein a mean grain size of the densified component is larger by a factor F than a mean grain size of the starting material, wherein: F<5.

11. An article comprising the densified component produced by the method according to claim 1, wherein the article is a device for generating light, wherein the article is configured such that the densified component can be subjected to an electric voltage and/or an electric field for emitting light.

12. (canceled)

13. (canceled)

14. The article according to claim 11, wherein the densified component has an average grain size between 0.8 μm and 20 μm.

15. (canceled)

16. The article according to claim 11, wherein the densified component has an average grain size between 1 μm and 10 μm.

17. The method according to claim 1, wherein the starting material is subjected to the electric field for a period of time (t) of less than 1 min.

18. The method according to claim 1, wherein the electric field has an electric field strength between 100 V/cm and 5 kV/cm.

19. The method according to claim 6, wherein the second material is an aluminium oxide.

20. The method according to claim 6, wherein at least one first region, in particular at least one first layer, of the starting material consists essentially of the first material and at least one second region, in particular at least one second layer, of the starting material consists essentially of the second material.

21. The method according to claim 7, wherein at least one first layer of the starting material consists essentially of the first material and at least one second layer of the starting material consists essentially of the second material.

22. The method according to claim 1, wherein a mean grain size of the densified component is larger by a factor F than a mean grain size of the starting material, wherein: F<2.

23. The method according to claim 1, wherein a mean grain size of the densified component is larger by a factor F than a mean grain size of the starting material, wherein: F<1.25.

Description

[0053] The figures show:

[0054] FIG. 1: a method for producing a densified component,

[0055] FIG. 2: a first configuration of a component,

[0056] FIG. 3: a second configuration of a component, and

[0057] FIG. 4: a third configuration of a component.

[0058] FIG. 1 schematically shows a method for producing a densified component 10. A starting material 20 is subjected to an electric field 12. In this, the starting material 20 is subjected to a temperature T below 800° C., in particular at the beginning of the effect of the electric field 12. The temperature T typically corresponds to room temperature. In other words, the component is not heated either before or during the action of the electric field 12. The electric field 12 acts for a period of time t of about 30 seconds. No pressure is applied, so that the starting material 20 is subjected to the electric field 12 under the prevailing atmospheric pressure P. The electric field strength is continuously increased, starting from 0 and/or up to a maximum value of 1 kV/cm.

[0059] FIG. 2 schematically shows a first configuration of a starting material 20 for producing a densified component. The starting material 20 comprises a third region 28 comprising a homogeneous mixture of a first material 14 from the group of cuprates and a second material 16. In particular, the starting material 20 consists of the third region 28. The second material 16 is different from the first material 14 and in particular does not include a cuprate. Suitable admixtures of the second material 16 can be used to selectively adjust properties of the densified component. At the same time, densification is possible with the method according to the invention.

[0060] FIG. 3 shows a second configuration of a starting material 20. The starting material 20 comprises a first region 24 and a second region 26, which are in the form of layers and are directly adjacent to one another. The first region 24 is produced from the first material 14 from the group of cuprates. The second region 26 is produced from the second material 16, which is different from the first material 14 and in particular does not include a cuprate. The coating of the first region 24 with the second material 16 can be done in such a way that properties of the densified component are influenced in a desired manner. For example, a colour temperature of the emitted light may be adjusted in a desired manner.

[0061] FIG. 4 shows a third configuration of a starting material 20. The starting material 20 comprises a second region 26, which is sandwiched between two first regions 24, which are in particular of the same type. In particular, the starting material 20 consists of said regions 24 and 26. Again, the first region 24 is produced from the first material 14 from the group of cuprates and the second region 26 is produced from the second material 16, which is different from the first material 14 and in particular does not include a cuprate. The first regions 24 and the second region 26 are arranged in superimposed layers.

[0062] The layer thicknesses shown in schematic FIGS. 2 to 4, as well as their ratios, are not to scale. The regions 14 and 16 can have the same or different layer thicknesses. The layer thickness of the first region 14 can be greater than, less than or equal to the layer thickness of the second region 16.

LIST OF REFERENCE SIGNS

[0063] component 10 [0064] starting material 20 [0065] first material 14 [0066] second material 16 [0067] first region 24 [0068] second region 26 [0069] third region 28 [0070] temperature T [0071] period of time t [0072] atmospheric pressure P