Honeycomb structure and manufacturing method of the same

Patent metadata

Field	Value
Publication number	US-9289722-B2
Application number	US-201414187867-A
Country	US
Kind code	B2
Filing date	Feb 24, 2014
Priority date	Mar 29, 2013
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

A honeycomb structure includes a tubular honeycomb structure body having porous partition walls to define and form a plurality of cells, and an outer peripheral wall; and a pair of electrode sections disposed on a side surface of the honeycomb structure body, an electrical resistivity of the honeycomb structure body is from 1 to 200 Ωcm, each of the pair of electrode sections is formed into a band shape extending in an extending direction of the cells, the electrode section is constituted of a porous body in which particles made of silicon carbide as an aggregate are bound by a binding material, silicon carbide as the aggregate constituting the electrode sections contains β-SiC having a stacking fault of 2% or less, and the binding material constituting the electrode sections contains silicon and a metal silicide.

First claim

What is claimed is:

1. A honeycomb structure comprising:
a tubular honeycomb structure body having porous partition walls to define and form a plurality of cells as through channels of a fluid which extend from a first end surface as one end surface to a second end surface as the other end surface, and an outer peripheral wall positioned on the outermost periphery; and
a pair of electrode sections disposed on a side surface of the tubular honeycomb structure body,
wherein an electrical resistivity of the tubular honeycomb structure body is from 1 to 200 Ωcm,
each of the pair of electrode sections is formed into a band shape extending in an extending direction of the plurality of cells of the tubular honeycomb structure body,
in a cross section perpendicular to the extending direction of the plurality of cells, one electrode section in the pair of electrode sections is disposed on a side opposite to the other electrode section in the pair of electrode sections via the center of the tubular honeycomb structure body,
each of the pair of electrode sections comprises a porous body in which particles made of silicon carbide as an aggregate are bound by a binding material,
silicon carbide as the aggregate constituting each of the pair of electrode sections contains β-SiC having a stacking fault of 2% or less, and
the binding material constituting each of the pair of electrode sections contains silicon and a metal silicide.

2. The honeycomb structure according to claim 1 , wherein a crystallite size of the β-SiC is 900 Å or more.

3. The honeycomb structure according to claim 1 ,
wherein silicon carbide as the aggregate contains 40 vol % or more of β-SiC having the stacking fault of 2% or less.

4. The honeycomb structure according to claim 1 , wherein a ratio of a volume of the binding material to a volume of silicon carbide as the aggregate is from 20/80 to 60/40.

5. The honeycomb structure according to claim 1 ,
wherein an average particle diameter of the particles made of silicon carbide as the aggregate is from 10 to 70 μm.

6. The honeycomb structure according to claim 1 ,
wherein the metal silicide to be contained in the binding material is a metal silicide of at least one selected from the group consisting of nickel and zirconium.

7. The honeycomb structure according to claim 1 ,
wherein a ratio of a volume of the metal silicide to a total volume of silicon carbide as the aggregate and the binding material is from 1 to 10 vol %.

8. The honeycomb structure according to claim 1 ,
wherein each of the pair of electrode sections further contains an alkaline earth metal oxide, Al 2 O 3 , and SiO 2 .

9. The honeycomb structure according to claim 8 , wherein the alkaline earth metal oxide is MgO.

10. The honeycomb structure according to claim 8 ,
wherein each of the pair of electrode sections contains the alkaline earth metal oxide, Al 2 O 3 , and SiO 2 as much as 1 to 10 parts by volume in total, when a total volume of silicon carbide as the aggregate and the binding material is 100 parts by volume.

11. The honeycomb structure according to claim 1 , wherein a thickness of each of the pair of electrode sections is from 50 to 300 μm.

12. The honeycomb structure according to claim 1 ,
wherein a porosity of each of the pair of electrode sections is from 10 to 60%.

13. The honeycomb structure according to claim 1 ,
wherein β-SiC having the stacking fault of 2% or less which is to be contained in silicon carbide as the aggregate is obtained by using silicon, a carbonaceous substance, and a transition metal to form the silicon into silicon carbide.

14. A manufacturing method of a honeycomb structure comprising:
an electrode section forming step of applying an electrode section forming raw material to each of a first region and a second region of a side surface of a tubular honeycomb formed body having partition walls to define and form a plurality of cells as through channels of a fluid which extend from a first end surface as one end surface to a second end surface as the other end surface, and an outer peripheral wall positioned on the outermost periphery, or a fired honeycomb body obtained by firing the honeycomb formed body, and drying and firing the applied electrode section forming raw material, to form a pair of electrode sections,
wherein in the electrode section forming step, the electrode section forming raw material is applied so that in a cross section perpendicular to an extending direction of the cells of the honeycomb formed body or the fired honeycomb body, the first region is positioned on a side opposite to the second region via the center of the honeycomb formed body or the fired honeycomb body, and the first and second regions are formed in a band shape extending in an extending direction of the plurality of cells of the honeycomb formed body or the fired honeycomb body,
the electrode section forming raw material includes particles made of silicon carbide as an aggregate and a metal silicide as a binding material, and particles made of silicon which becomes a binding material, and silicon carbide as the aggregate contains β-SiC having a stacking fault of 2% or less, and
wherein an electrical resistivity of the fired honeycomb body is 1 to 200 Ωcm.

15. The manufacturing method of the honeycomb structure according to claim 14 ,
wherein β-SiC having the stacking fault of 2% or less which is to be contained in silicon carbide as the aggregate is obtained by using an aggregate material including silicon, a carbonaceous substance, and a transition metal.

16. The manufacturing method of the honeycomb structure according to claim 15 ,
wherein the carbonaceous substance to be included in the aggregate material is carbon black.

17. The manufacturing method of the honeycomb structure according to claim 15 ,
wherein the transition metal to be included in the aggregate material is at least one selected from the group consisting of nickel and zirconium.

18. The manufacturing method of the honeycomb structure according to claim 15 ,
wherein the silicon to be included in the aggregate material is a particulate material having an average particle diameter of 50 μm or more.

Assignees

• Ngk Insulators Ltd

Inventors

• Kikuchi Yoshio
• Suzuki Takashi

Classifications

• C04B2235/5409

  expressed by specific surface values · CPC title

• C04B2235/762

  Cubic symmetry, e.g. beta-SiC · CPC title

• C04B2235/3481

  Alkaline earth metal alumino-silicates other than clay, e.g. cordierite, beryl, micas such as margarite, plagioclase feldspars such as anorthite, zeolites such as chabazite · CPC title

• C04B2235/658

  Atmosphere during thermal treatment · CPC title

• C04B2235/785

  Submicron sized grains, i.e. from 0,1 to 1 micron · CPC title