Refractory object and process of forming a glass sheet using the refractory object

Patent metadata

Field	Value
Publication number	US-2016107936-A1
Application number	US-201514984539-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	Jan 11, 2012
Publication date	Apr 21, 2016
Grant date	—

Abstract

A refractory object can include at least approximately 10 wt % Al 2 O 3 and at least approximately 1 wt % SiO 2 . In an embodiment, the refractory object can include an additive. In a particular embodiment, the additive can include TiO 2 , Y 2 O 3 , SrO, BaO, CaO, Ta 2 O 5 , Fe 2 O 3 , ZnO, or MgO. The refractory object can include at least approximately 3 wt % of the additive. In an additional embodiment, the refractory object can include no greater than approximately 8 wt % of the additive. In a further embodiment, the creep rate of the refractory object can be at least approximately 1×10 −6 h −1 . In another embodiment, the creep rate of the refractory object can be no greater than approximately 5×10 −5 h −1 . In an illustrative embodiment, the refractory object can include a glass overflow trough or a forming block.

First claim

What is claimed is:

1 . A refractory object comprising:
Al 2 O 3 at a content in a range of approximately 10 wt % Al 2 O 3 to approximately 94 wt % Al 2 O 3 ; SiO 2 at a content of at least approximately 1.1 wt % SiO 2 ; an additive at a content of at least 0.2 wt % additive, wherein the additive includes TiO 2 , Y 2 O 3 , CaO, MgO, or any combination thereof; and wherein a creep rate of the refractory object is no greater than approximately 1×10 −4 h −1 .

2 . The refractory object as recited in claim 1 , wherein the apparent porosity of the refractory object is no greater than approximately 0.8 vol %.

3 . The refractory object as recited in claim 1 , wherein the refractory object includes no greater than approximately 8 wt % of the additive.

4 . The refractory object as recited in claim 1 , wherein the refractory object includes no greater than approximately 1 wt % of an alkali metal oxide.

5 . The refractory object as recited in claim 1 , wherein the refractory object includes at least approximately 0.2 wt % Y 2 O 3 .

6 . The refractory object as recited in claim 1 , wherein the refractory object comprises no greater than approximately 0.3 wt % ZrO 2 .

7 . The refractory object as recited in claim 1 , wherein the refractory object includes at least approximately 0.2 wt % TiO 2 .

8 . The refractory object as recited in claim 7 , wherein the refractory object includes no greater than approximately 4.0 wt % TiO 2 .

9 . The refractory object as recited in claim 1 , wherein the refractory object comprises at least approximately 70 wt % Al 2 O 3 .

10 . The refractory object as recited in claim 1 , wherein a fracture toughness of the refractory object is at least approximately 2.1 MPa-m 1/2 .

11 . The refractory object as recited in claim 1 , wherein the refractory object further comprises a silica phase.

12 . The refractory object as recited in claim 1 , wherein the refractory object includes a peripheral region disposed between an edge of the refractory object and the body portion and outside of the body portion.

13 . The refractory object as recited in claim 11 , wherein a melting point of the silica phase is at least approximately 1300° C.

14 . The refractory object as recited in claim 13 , wherein the melting point of the silica phase is at least approximately a sintering temperature used in forming the refractory object.

15 . The refractory object as recited in claim 1 , wherein the SiO 2 is provided as amorphous SiO 2 , crystalline SiO 2 , or a combination thereof.

Assignees

• Saint Gobain Abrasives Inc
• Saint Gobain Abrasifs Sa

Inventors

• Citti Olivier
• Fourcade Julien P
• Kazmierczak Andrea L

Classifications

• Y02P40/57

  Improving the yield, e-g- reduction of reject rates · CPC title

• C04B35/62685

  characterised by the order of addition of constituents or additives · CPC title

• C04B2235/3201

  Alkali metal oxides or oxide-forming salts thereof · CPC title

• C04B2235/77

  Density · CPC title

• C04B2235/604

  Pressing at temperatures other than sintering temperatures · CPC title