Ceramic product and method for its manufacture

• US 9,631,995 B2
• Filed: 11/10/2010
• Issued: 04/25/2017
• Est. Priority Date: 12/17/2009
• Status: Active Grant

• Current Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Original Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Inventors: Roberg, Andreas, Schleiferbck, Detlef, Berlinger, Andrea, Drewes, Ulfert, Schmidt, Elke
• Primary Examiner(s): Patel, Harshad R
• Assistant Examiner(s): HOPKINS, BRANDI N
• Application Number:
  US13/515,342
• Publication Number:
  US 20120258322A1
• Time in Patent Office: 2,358 Days
• CPC Class Codes: C04B 2237/122 based on refractory metals
• CPC Class Codes: C04B 2237/343 Alumina or aluminates
• CPC Class Codes: C04B 2237/403 Refractory metals
• CPC Class Codes: C04B 2237/708 of one or more of the interlayers
• CPC Class Codes: C04B 2237/72 Forming laminates or joined articles comprising at least two interlayers directly next to each other
• CPC Class Codes: C04B 37/006 consisting of metals or metal salts
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A ceramic product includes a first ceramic part and a second ceramic part, wherein the first ceramic part is connected with the second ceramic part via a joint, wherein the joint comprises an active hard solder, or braze, characterized in that the joint has an inhomogeneous distribution of the components of the active hard solder, or braze, wherein at least at an interface between the active hard solder, or braze, and the ceramic, the at least one active component of the active hard solder, or braze, is enriched. For manufacture of the product, the active hard solder, or braze, material is provided in such a manner, that at least one surface section of at least one of the ceramic parts is first coated with at least one active component of the active hard solder, or braze, and that on the coated section, an alloy is provided, which, by melting of the alloy during the heating, alloys with the coating and forms a metal joint between the two ceramic parts.

Claims

1. A ceramic product, comprising:

at least a first ceramic part and a second ceramic part, wherein;

said first ceramic part is connected with said second ceramic part via a joint;

said joint having a thickness;

said joint comprises an active hard solder, or braze, said active hard solder, or braze, comprising at least one active component, said active component having a location-dependent concentration

said joint has an inhomogeneous distribution of the components of the active hard solder, or braze, and at least at an interface between the active hard solder, or braze, and the ceramic, said active component of the active hard solder, or braze, is enriched, wherein;

2. The ceramic product as claimed in claim 1, wherein:

a>

1.1.

3. The ceramic product as claimed in claim 1, wherein:

a>

1.3.

4. The ceramic product as claimed in claim 1, wherein:

the ceramic product is a pressure sensor; and

the ceramic parts comprise a platform and a measuring membrane.

5. The ceramic product as claimed in claim 1, wherein:

the joint comprises a ternary Zr—

Ni—

Ti alloy with c_Zr mass % Zr, c_Ni mass % Ni and c_Ti mass % Ti, wherein 100>

c_Zr+c_Ni+c_Ti≧

100−

R, with R<

0.5.

6. The ceramic product as claimed in claim 5, wherein:

R<

0.3.

7. The ceramic product as claimed in claim 5, wherein:

R<

0.25.

8. The ceramic product as claimed in claim 5, wherein:

concentrations of components of the alloy lie in the ranges, 55<

c_Zr<

65.5, 20.5<

c_Ni<

27.5 and 14<

c_Ti<

17.5.

9. The ceramic product as claimed in claim 5, wherein:

concentrations of components of the alloy lie in the ranges, 61<

c_Zr<

63.5, 21.5<

c_Ni<

24 and 14.5<

c_Ti<

15.5.

10. The ceramic product as claimed in claim 1, wherein:

said first ceramic part and/or said second ceramic part comprise aluminum oxide, said aluminum oxide comprising aluminum atoms;

a boundary region is present, in which a concentration of aluminum atoms in the active hard solder, or braze, diffused in from said first or second ceramic part is larger than the concentration of Ni-atoms in this region, wherein said region extends not less than 10 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

11. The ceramic product as claimed in claim 10, wherein:

said boundary region extends not less than 40 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

12. The ceramic product as claimed in claim 10, wherein:

said boundary region extends not less than 80 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

13. A ceramic product, comprising:

at least a first ceramic part and a second ceramic part, wherein;

said first ceramic part is connected with said second ceramic part via a joint;

said joint having a thickness;

said joint comprises an active hard solder, or braze, said active hard solder, or braze, comprising at least one active component;

said at least one active component having a location-dependent concentration;

said joint has an inhomogeneous distribution of the components of the active hard solder, or braze, and at least at an interface between the active hard solder, or braze, and the ceramic, said active component of the active hard solder, or braze, is enriched, wherein;

14. The ceramic product as claimed in claim 13, wherein:

a>

1.5.

15. The ceramic product as claimed in claim 13, wherein:

a>

1.7.

16. The ceramic product as claimed in claim 13, wherein:

the ceramic product is a pressure sensor, wherein the ceramic parts comprise a platform and a measuring membrane.

17. The ceramic product as claimed in claim 13, wherein:

the joint comprises a ternary Zr—

Ni—

Ti alloy with c_Zr mass % Zr, c_Ni mass % Ni and c_Ti mass % Ti, wherein 100>

c_Zr+c_Ni+c_Ti≧

100−

R, with R<

0.5.

18. The ceramic product as claimed in claim 17, wherein:

R<

0.3.

19. The ceramic product as claimed in claim 17, wherein:

R<

0.25.

20. The ceramic product as claimed in claim 17, wherein:

concentrations of components of the alloy lie in the ranges, 55<

c_Zr<

65.5, 20.5<

c_Ni<

27.5 and 14<

c_Ti<

17.5.

21. The ceramic product as claimed in claim 17, wherein:

concentrations of components of the alloy lie in the ranges, 61<

c_Zr<

63.5, 21.5<

c_Ni<

24 and 14.5<

c_Ti<

15.5.

22. The ceramic product as claimed in claim 13, wherein:

said first ceramic part and/or said second ceramic part comprise aluminum oxide, said aluminum oxide comprising aluminum atoms;

a boundary region is present, in which a concentration of aluminum atoms in the active hard solder, or braze, diffused in from said first or second ceramic part is larger than the concentration of Ni-atoms in this region, wherein said region extends not less than 10 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

23. The ceramic product as claimed in claim 22, wherein:

said region extends not less than 40 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.

24. The ceramic product as claimed in claim 22, wherein:

said region extends not less than 80 nm from the interface between the ceramic part and the active hard solder, or braze, in the direction of the active hard solder, or braze.