Ceramic formed body extrusion method, ceramic formed body, and ceramic porous body

Patent metadata

Field	Value
Publication number	US-2017282402-A1
Application number	US-201715471327-A
Country	US
Kind code	A1
Filing date	Mar 28, 2017
Priority date	Mar 30, 2016
Publication date	Oct 5, 2017
Grant date	—

Abstract

A ceramic formed body extrusion method for forming a ceramic formed body having a wall-shaped or plate-shaped formed portion by using an extrusion die provided with a slit for extrusion of a ceramic formed body from a raw material for forming, the slit including a slit former stage unit located on an upstream side in an extrusion direction in the extrusion and a slit latter stage unit located on a downstream side in the extrusion direction, the slit latter stage unit having a width of three to 27 times a width of the slit former stage unit, and by extruding a raw material containing a first particle having an aspect ratio of two or more and less than 300 such that the raw material passes though the slit former stage unit of the extrusion die and then passes through the slit latter stage unit.

First claim

What is claimed is:

1 . A ceramic formed body extrusion method for forming a ceramic formed body having a wall-shaped or plate-shaped formed portion,
by using an extrusion die provided with a slit for extrusion of a ceramic formed body having a wall-shaped or plate-shaped formed portion from a raw material for forming, the slit including a slit former stage unit located on an upstream side in an extrusion direction in the extrusion and a slit latter stage unit located on a downstream side in the extrusion direction, the slit latter stage unit having a width of three to 27 times a width of the slit former stage unit, and by extruding a raw material containing a first particle having an aspect ratio of two or more and less than 300 such that the raw material passes though the slit former stage unit of the extrusion die and then passes through the slit latter stage unit.

2 . The ceramic formed body extrusion method according to claim 1 , wherein a length of the first particle is 50% or less of a width of the slit latter stage unit.

3 . The ceramic formed body extrusion method according to claim 1 , wherein the first particle is a pore former.

4 . The ceramic formed body extrusion method according to claim 1 , wherein an addition amount of the first particle is 70% by volume or less with respect to a whole of the raw material.

5 . The ceramic formed body extrusion method according to claim 1 , wherein the width of the slit latter stage unit is 8 mm or less.

6 . The ceramic formed body extrusion method according to claim 1 , wherein the length of the slit latter stage unit in the extrusion direction is 13 mm or less.

7 . The ceramic formed body extrusion method according to claim 1 , wherein the raw material contains at least one ceramic raw material selected from the group consisting of silicon carbide, cordierite, aluminum titanate, zirconia, aluminum oxide, a silicon carbide forming raw material, a cordierite forming raw material, an aluminum titanate forming raw material, and a zirconia forming raw material.

8 . The ceramic formed body extrusion method according to claim 1 , wherein the extrusion die has at least one introduction hole communicating with the slit and provided to introduce the raw material into the slit.

9 . The ceramic formed body extrusion method according to claim 1 , wherein the ceramic formed body is a honeycomb-shaped ceramic formed body having partition walls for defining a plurality of cells, and the partition wall is the wall-shaped or plate-shaped formed portion.

10 . The ceramic formed body extrusion method according to claim 1 , wherein the raw material contains a second particle having an aspect ratio of less than two, and the second particle is a pore former.

11 . A ceramic formed body with a wall-shaped or plate-shaped formed portion, comprising a first particle having an aspect ratio of two or more and less than 300, wherein in a dry state, among three regions obtained by equally dividing a cut surface obtained by cutting the formed portion in a thickness direction thereof into three parts in the thickness direction of the formed portion, the orientation degree of the first particle in a region located in the center in the thickness direction of the formed portion is from 0 to 53°.

12 . The ceramic formed body according to claim 11 , wherein a length of the first particle is 50% or less of a thickness of the formed portion.

13 . The ceramic formed body according to claim 11 , wherein the first particle is a pore former.

14 . The ceramic formed body according to claim 11 , wherein a content of the first particle is 45% by volume or less with respect to a whole of the raw material constituting the ceramic formed body.

15 . The ceramic formed body according to claim 11 , wherein the ceramic formed body is a honeycomb-shaped ceramic formed body having partition walls for defining a plurality of cells, and the partition wall is the wall-shaped or plate-shaped formed portion.

16 . The ceramic formed body according to claim 11 , further comprising a second particle having an aspect ratio of less than two, wherein the second particle is a pore former.

17 . A ceramic porous body comprising partition walls having a plurality of pores for defining a plurality of cells, wherein
among three regions obtained by equally dividing a cut surface obtained by cutting the ceramic porous body in a thickness direction of the partition walls into three parts in the thickness direction of the partition walls, the orientation degree of the pores in a central region located in the center in the thickness direction of the partition walls is from 0 to 53°, and among the three regions, a difference between a porosity in a surface region outside the central region and a porosity of the partition walls is from 0 to 11%.

18 . The ceramic porous body according to claim 17 , wherein the porosity of the partition walls is 65% or less.

Assignees

• Ngk Insulators Ltd

Inventors

• Kimata Takafumi
• Hidaka Kenichi
• Kikuchi Yoshio
• Ishikawa Masaki
• Yamamoto Kisuke
• Morimoto Kenji

Classifications

• B28B3/26 Primary

  Extrusion dies · CPC title

• B28B3/269 Primary

  For multi-channeled structures, e.g. honeycomb structures · CPC title

• B28B11/16

  for extrusion {or for materials supplied in long webs} · CPC title

• B28B2003/203

  for multi-channelled structures, e.g. honeycomb structures · CPC title