Graphite-containing refractory and method of producing graphite-containing refractory

Patent metadata

Field	Value
Publication number	US-11156403-B2
Application number	US-201816487248-A
Country	US
Kind code	B2
Filing date	Feb 1, 2018
Priority date	Feb 24, 2017
Publication date	Oct 26, 2021
Grant date	Oct 26, 2021

Abstract

A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 μm/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

First claim

The invention claimed is:

1. A graphite-containing refractory comprising:
carbon fiber bundles 100 mm or more in length placed therein, the carbon fiber bundles being formed of 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 μm/fiber, and
a magnesia carbon raw material including graphite and a magnesia raw material, the magnesia raw material constituting 20% to 99% by mass of the magnesia carbon raw material and the graphite content constituting 1% to 80% by mass of the magnesia carbon raw material,
wherein end faces of the carbon fiber bundles are a flat shape, and
the carbon fiber bundles are placed such that longitudinal directions of the end faces of the carbon fiber bundles are the same and that an angle between a pressing surface and the longitudinal direction of each end face is 45 degrees or more and 135 degrees or less.

2. The graphite-containing refractory according to claim 1 , wherein the carbon fiber bundles are formed of 1000 to 60000 carbon fibers.

3. The graphite-containing refractory according to claim 1 , wherein the carbon fiber bundles are formed by bonding using at least one adhesive selected from the group consisting of a phenolic resin, an epoxy resin, a melamine resin, a urea resin, an alkyd resin, an unsaturated polyester resin, polyurethane, thermosetting polyimide, an alumina sol, a silica sol, a zirconia sol, a chromia sol, a titania sol, a magnesia sol, a calcia sol, an yttria sol, pitch, tar, and a starch paste.

4. The graphite-containing refractory according to claim 1 , further comprising short carbon fibers constituting 0.10% to 10% by mass based on 100% by mass of the magnesia carbon raw material, the short carbon fibers having a fiber diameter of 1 to 45 μm/fiber, a fiber length of 1 mm or less, and a ratio of fiber length to fiber diameter (fiber length/fiber diameter) of 2 to 1000.

5. A graphite-containing refractory with a graphite content of 1% to 80% by mass, comprising:
carbon fiber bundles 100 mm or more in length placed therein, the carbon fiber bundles being formed of 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 μm/fiber, and
a graphite-containing refractory raw material including an alumina raw material constituting 10% to 95% by mass of the graphite-containing refractory raw material and a silicon carbide raw material constituting 1% or more by mass of the graphite-containing refractory raw material,
wherein end faces of the carbon fiber bundles are a flat shape, and
the carbon fiber bundles are placed such that longitudinal directions of the end faces of the carbon fiber bundles are the same and that an angle between a pressing surface and the longitudinal direction of each end face is 45 degrees or more and 135 degrees or less.

6. The graphite-containing refractory according to claim 5 , wherein the graphite-containing refractory raw material further comprises a silica raw material constituting 1% to 50% by mass of the graphite-containing refractory raw material.

7. The graphite-containing refractory according to claim 5 , wherein the carbon fiber bundles are formed of 1000 to 60000 carbon fibers.

8. The graphite-containing refractory according to claim 5 , wherein the carbon fiber bundles are formed by bonding using at least one adhesive selected from the group consisting of a phenolic resin, an epoxy resin, a melamine resin, a urea resin, an alkyd resin, an unsaturated polyester resin, polyurethane, thermosetting polyimide, an alumina sol, a silica sol, a zirconia sol, a chromia sol, a titania sol, a magnesia sol, a calcia sol, an yttria sol, pitch, tar, and a starch paste.

9. The graphite-containing refractory according to claim 5 , further comprising short carbon fibers constituting 0.10% to 10% by mass based on 100% by mass of the graphite-containing refractory raw material, the short carbon fibers having a fiber diameter of 1 to 45 μm/fiber, a fiber length of 1 mm or less, and a ratio of fiber length to fiber diameter (fiber length/fiber diameter) of 2 to 1000.

10. A graphite-containing refractory with a graphite content of 1% to 80% by mass, comprising:
carbon fiber bundles 100 mm or more in length placed therein, the carbon fiber bundles being formed of 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 μm/fiber, and
a graphite-containing refractory raw material including a refractory waste constituting 10% to 90% by mass of the graphite-containing refractory raw material, the refractory waste being a crushed used refractory,
wherein end faces of the carbon fiber bundles are a flat shape, and
the carbon fiber bundles are placed such that longitudinal directions of the end faces of the carbon fiber bundles are the same and that an angle between a pressing surface and the longitudinal direction of each end face is 45 degrees or more and 135 degrees or less.

11. The graphite-containing refractory according to claim 10 , wherein the carbon fiber bundles are formed of 1000 to 60000 carbon fibers.

12. The graphite-containing refractory according to claim 10 , wherein the carbon fiber bundles are formed by bonding using at least one adhesive selected from the group consisting of a phenolic resin, an epoxy resin, a melamine resin, a urea resin, an alkyd resin, an unsaturated polyester resin, polyurethane, thermosetting polyimide, an alumina sol, a silica sol, a zirconia sol, a chromia sol, a titania sol, a magnesia sol, a calcia sol, an yttria sol, pitch, tar, and a starch paste.

13. The graphite-containing refractory according to claim 10 , further comprising short carbon fibers constituting 0.10% to 10% by mass based on 100% by mass of the graphite-containing refractory raw material, the short carbon fibers having a fiber diameter of 1 to 45 μm/fiber, a fiber length of 1 mm or less, and a ratio of fiber length to fiber diameter (fiber length/fiber diameter) of 2 to 1000.

Assignees

• Jfe Steel Corp

Inventors

• Yoshida Keisuke
• Matsunaga Hisahiro
• Hama Yoichiro

Classifications

• C04B2235/9676

  against molten metals such as steel or aluminium · CPC title

• C04B2235/96

  Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance · CPC title

• C04B2235/80

  Phases present in the sintered or melt-cast ceramic products other than the main phase · CPC title

• C04B2235/5296

  with a defined aspect ratio, e.g. indicating sphericity · CPC title

• C04B35/632

  Organic additives · CPC title