Spark plug electrode material and spark plug

Patent metadata

Field	Value
Publication number	US-9166380-B2
Application number	US-201214111863-A
Country	US
Kind code	B2
Filing date	Feb 15, 2012
Priority date	Apr 15, 2011
Publication date	Oct 20, 2015
Grant date	Oct 20, 2015

Abstract

A spark plug electrode material containing nickel, silicon, and copper, the electrode material, in the case of proper use, forming a nickel oxide layer made of nickel oxide grains on at least a part of its surface, the grain boundary phase of the nickel oxide grains including silicon and/or silicon oxide.

First claim

What is claimed is:

1. A spark plug electrode material, comprising:
nickel, silicon, and copper, wherein the electrode material forms a nickel oxide layer made of nickel oxide grains on at least a part of its surface as a result of exposure to an oxidizing and high temperature environment, a grain boundary phase of the nickel oxide grains including at least one of silicon and silicon oxide.

2. The spark plug electrode material as recited in claim 1 , wherein the grain boundary phase of the nickel oxide grains further includes at least one of copper and copper oxide.

3. The spark plug electrode material as recited in claim 1 , wherein a content of the at least one of silicon and silicon oxide in the nickel oxide layer is 1 wt.-% to 5 wt.-%.

4. The spark plug electrode material as recited in claim 1 , wherein approximately 90% of the nickel oxide grains have a grain size of less than 15 μm.

5. The spark plug electrode material as recited in claim 1 , wherein, before the exposure, the content of silicon is 0.7 wt.-% to 1.3 wt.-%.

6. The spark plug electrode material as recited in claim 5 , wherein, before the exposure: the content of copper is 0.5 wt.-% to 1.0 wt.-%, and the content of nickel is approximately 97.5 wt.-% to 98.5 wt.-%.

7. The spark plug electrode material as recited in claim 1 , wherein a layer thickness of the grain boundary phases is less than 0.3 μm.

8. The spark plug electrode material as recited in claim 1 , further comprising 0.07 wt.-% to 0.13 wt.-% yttrium.

9. The spark plug electrode material as recited in claim 1 , wherein a proportion of metallic impurities is in total less than 0.2 wt.-%.

10. The spark plug electrode material as recited in claim 1 , wherein the nickel oxide grains do not contain any of the at least one of silicon and silicon oxide.

11. The spark plug electrode material as recited in claim 1 , wherein the electrode material is essentially free of at least one of aluminum, aluminum compounds, and intermetallic phases.

12. The spark plug electrode material as recited in claim 1 , wherein a combined content of any of iron, chromium, and titanium is less than 0.05 wt.-%.

13. The spark plug electrode material as recited in claim 12 , wherein a combined content of any of sulfur, sulfur compounds, carbon, and carbon compounds is less than 0.01 wt.-%.

14. The spark plug electrode material as recited in claim 1 , wherein a content of oxygen is less than 0.003 wt.-%.

15. The spark plug electrode material as recited in claim 1 , wherein the electrode material includes: (a) approximately 98.15 wt.-% nickel, (b) 1 wt.-% silicon, (c) 0.75 wt.-% copper, and (d) 0.1 wt.-% yttrium.

16. The spark plug electrode material as recited in claim 1 , wherein, before the exposure, the content of nickel is approximately 97.5 wt.-% to 98.5 wt.-%.

17. The spark plug electrode material as recited in claim 1 , wherein, before the exposure, the content of copper is 0.5 wt.-% to 1.0 wt.-%.

18. The spark plug electrode material as recited in claim 1 , wherein a combined content of any of sulfur, sulfur compounds, carbon, and carbon compounds is less than 0.01 wt.-%.

19. A method for manufacturing a spark plug electrode material including nickel, silicon, and copper, wherein the electrode material forms a nickel oxide layer made of nickel oxide grains on at least a part of its surface as a result of exposure to an oxidizing and high temperature environment, a grain boundary phase of the nickel oxide grains including at least one of silicon and silicon oxide, the method comprising:
manufacturing a nickel-based alloy; and
adding further elements.

20. A spark plug including an electrode made of a spark plug electrode material including nickel, silicon, and copper, wherein the electrode material forms a nickel oxide layer made of nickel oxide grains on at least a part of its surface as a result of exposure to an oxidizing and high temperature environment, a grain boundary phase of the nickel oxide grains including at least one of silicon and silicon oxide.

21. The spark plug as recited in claim 20 , wherein the electrode is a center electrode with a copper core.

22. The spark plug as recited in claim 20 , wherein the electrode is a center electrode without a copper core.

23. The spark plug as recited in claim 20 , wherein the electrode is a ground electrode with a copper core.

24. The spark plug as recited in claim 20 , wherein the electrode is a ground electrode without a copper core.

25. A method of manufacturing a spark plug electrode material, comprising:
providing and using an alloy that includes nickel, silicon, and copper, wherein at least one of:
a composition of the alloy is such that, when exposed to an oxidizing and high temperature environment, a nickel oxide layer forms, the nickel oxide layer including nickel oxide grains separated by grain boundary phases, with at least a predominant amount of at least one of copper and copper oxide in the nickel oxide layer being included in the nickel oxide grains and with at least a predominant amount of at least one of silicon and silicon oxide in the nickel oxide layer being included in the grain boundary phases; and
the alloy further includes 0.07 wt.-% to 0.13 wt.-% yttrium.

Assignees

• Baus Simone
• Bosch Gmbh Robert

Inventors

• Baus Simone

Classifications

• C22C19/05

  with chromium · CPC title

• H01T13/39 Primary

  Selection of materials for electrodes · CPC title

• H01T21/02

  of sparking plugs · CPC title

• C22C19/03

  based on nickel · CPC title

• C22F1/10

  of nickel or cobalt or alloys based thereon · CPC title