CA1150323A - Fireproof material for steel-casting foundry equipment - Google Patents
Fireproof material for steel-casting foundry equipmentInfo
- Publication number
- CA1150323A CA1150323A CA000371886A CA371886A CA1150323A CA 1150323 A CA1150323 A CA 1150323A CA 000371886 A CA000371886 A CA 000371886A CA 371886 A CA371886 A CA 371886A CA 1150323 A CA1150323 A CA 1150323A
- Authority
- CA
- Canada
- Prior art keywords
- brick
- foundry
- steel
- weight
- cao
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000000463 material Substances 0.000 title claims abstract description 22
- 238000005266 casting Methods 0.000 title claims description 8
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 29
- 239000010959 steel Substances 0.000 claims abstract description 29
- 239000011449 brick Substances 0.000 claims abstract description 28
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000002893 slag Substances 0.000 claims abstract description 10
- 239000000654 additive Substances 0.000 claims abstract description 7
- 229910052681 coesite Inorganic materials 0.000 claims abstract description 7
- 229910052906 cristobalite Inorganic materials 0.000 claims abstract description 7
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 7
- 235000012239 silicon dioxide Nutrition 0.000 claims abstract description 7
- 229910052682 stishovite Inorganic materials 0.000 claims abstract description 7
- 229910052905 tridymite Inorganic materials 0.000 claims abstract description 7
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 claims abstract description 5
- 230000000996 additive effect Effects 0.000 claims abstract description 5
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000000203 mixture Substances 0.000 claims description 3
- 229910000287 alkaline earth metal oxide Inorganic materials 0.000 claims description 2
- NWXHSRDXUJENGJ-UHFFFAOYSA-N calcium;magnesium;dioxido(oxo)silane Chemical compound [Mg+2].[Ca+2].[O-][Si]([O-])=O.[O-][Si]([O-])=O NWXHSRDXUJENGJ-UHFFFAOYSA-N 0.000 claims description 2
- 229910052637 diopside Inorganic materials 0.000 claims description 2
- 239000001095 magnesium carbonate Substances 0.000 claims description 2
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 claims description 2
- 229910000021 magnesium carbonate Inorganic materials 0.000 claims description 2
- 235000014380 magnesium carbonate Nutrition 0.000 claims description 2
- 238000000034 method Methods 0.000 claims description 2
- 239000010456 wollastonite Substances 0.000 claims description 2
- 229910052882 wollastonite Inorganic materials 0.000 claims description 2
- 239000010450 olivine Substances 0.000 claims 1
- 229910052609 olivine Inorganic materials 0.000 claims 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 abstract 2
- 239000012535 impurity Substances 0.000 abstract 2
- 239000002245 particle Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 230000007547 defect Effects 0.000 description 3
- 239000004927 clay Substances 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 229910000655 Killed steel Inorganic materials 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- -1 olevine Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D1/00—Casings; Linings; Walls; Roofs
- F27D1/0003—Linings or walls
- F27D1/0006—Linings or walls formed from bricks or layers with a particular composition or specific characteristics
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D35/00—Equipment for conveying molten metal into beds or moulds
- B22D35/04—Equipment for conveying molten metal into beds or moulds into moulds, e.g. base plates, runners
- B22D35/045—Runner base plates for bottom casting ingots
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/14—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silica
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/16—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay
- C04B35/18—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay rich in aluminium oxide
- C04B35/195—Alkaline earth aluminosilicates, e.g. cordierite or anorthite
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Ceramic Products (AREA)
- Mold Materials And Core Materials (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The invention is a fireproof material suitable for use in foundry runner bricks. The material comprises from 20 to 30%
by weight of A?2O3, from 60 to 70% by weight of SiO2 and from 1.5 to 10% by weight of an additive oxide which is CaO or MgO.
It may also contain up to 10% by weight of TiO2, Fe2O3 or Na2O.
In contact with molten steel there is generated slag which dissolves impurities in the steel. The slag containing the impurities is readily separable from the steel.
The invention is a fireproof material suitable for use in foundry runner bricks. The material comprises from 20 to 30%
by weight of A?2O3, from 60 to 70% by weight of SiO2 and from 1.5 to 10% by weight of an additive oxide which is CaO or MgO.
It may also contain up to 10% by weight of TiO2, Fe2O3 or Na2O.
In contact with molten steel there is generated slag which dissolves impurities in the steel. The slag containing the impurities is readily separable from the steel.
Description
The present invention relates to a fireproof material suitable for bricks such as runner bricks as used for and in the casting of steel.
It is known to use high-grade, abrasion-proof fire clay bricks in foundry equipment, e.g., for constructing runners. These bricks are to minimize the inclusion of nonmetallic, endogenous substances in steel. Such inclusions generally may originate in the brick material, are often quite coarse, and produce defects in the steel. These defects may be so extensive that large parts of the melt have to be downgraded or are not even usable at all.
It has been found in particular that casting of aluminum-killed steel is susceptible to further defects resulting from the inclusion of clay particles which are the residue of a deoxidizing treatment of the steel. These types of inclusions are particularly vexing because they tend to cluster in the steel. It is believed that rather fine AQ2O3 particles precipitate first from the steel and are deposited on the wall. These particles coagulate and form larger particles. Later, during continued casting, these grown particles are torn off the wall and are carried further into the melt; they may not precipitate again. It is this kind of coarse matter inclusion which tends to produce a relatively large amount of low-grade or unusable steel.
It is an object of the present invention to provide a new material for making fireproof bricks to be used in equipment for the casting of steel, and avoiding the deficiencies outlined above.
, . . . . .
.
.
'- ' ~, i323 Accordingly in one aspect the present invention provides a foundry brick suitable for use in contact with molten steel and formed of a fireproof material, which comprises from 20 to 30% by weight of A12O3, from 60 to 70% by weight of SiO2 and from 1.5 to 10% by weight of an additive oxide which is CaO
or MgO the composition of the brick being such that in use and in contact with molten steel the brick material will form a slag in which deoxidizing products in the steel dissolve and are thereby separated from the steel.
In accordance with a preferred embodiment of the present invention, it is proposed to use a composition which is composed, basically, of 20% to 32%
A12O3 and 60% to 70% SiO2, to which further, additive oxides are added, such as Tio2, Fe203 and/or Na2O at less than 10% total; and CaO and MgO is added at a combined quantity of 1.5% to 10% (all percentages by weight). Either one or both of these additives (CaO, MgO) is preferably in the form of fine grain, basic blast furnace slag, a mineral such as olevine, magnesite, diopside, horneblende or wollastonite. The grain size should not exceed 100 ~m. Prefer-ably the fireproof material containg no alkaline earth metal oxide other than CaO or MgO.
In another aspect the invention provides in a process of casting steel the improvement of using,as foundry runner bricks, bricks as defined above.
The material, in accordance with the invention, when used in foundry equipment for interfacing with molten steel, is positively intended to cause the hot steel to dissolve the fireproof material. The invention is based upon the surprising discovery that the deoxidizing products in the steel coact with the brick material in such a manner that, over the entire casting process, a liquid slag phase is formed in the brick-steel interface involving particularly the novel brick material and the dioxidizing . ..
It is known to use high-grade, abrasion-proof fire clay bricks in foundry equipment, e.g., for constructing runners. These bricks are to minimize the inclusion of nonmetallic, endogenous substances in steel. Such inclusions generally may originate in the brick material, are often quite coarse, and produce defects in the steel. These defects may be so extensive that large parts of the melt have to be downgraded or are not even usable at all.
It has been found in particular that casting of aluminum-killed steel is susceptible to further defects resulting from the inclusion of clay particles which are the residue of a deoxidizing treatment of the steel. These types of inclusions are particularly vexing because they tend to cluster in the steel. It is believed that rather fine AQ2O3 particles precipitate first from the steel and are deposited on the wall. These particles coagulate and form larger particles. Later, during continued casting, these grown particles are torn off the wall and are carried further into the melt; they may not precipitate again. It is this kind of coarse matter inclusion which tends to produce a relatively large amount of low-grade or unusable steel.
It is an object of the present invention to provide a new material for making fireproof bricks to be used in equipment for the casting of steel, and avoiding the deficiencies outlined above.
, . . . . .
.
.
'- ' ~, i323 Accordingly in one aspect the present invention provides a foundry brick suitable for use in contact with molten steel and formed of a fireproof material, which comprises from 20 to 30% by weight of A12O3, from 60 to 70% by weight of SiO2 and from 1.5 to 10% by weight of an additive oxide which is CaO
or MgO the composition of the brick being such that in use and in contact with molten steel the brick material will form a slag in which deoxidizing products in the steel dissolve and are thereby separated from the steel.
In accordance with a preferred embodiment of the present invention, it is proposed to use a composition which is composed, basically, of 20% to 32%
A12O3 and 60% to 70% SiO2, to which further, additive oxides are added, such as Tio2, Fe203 and/or Na2O at less than 10% total; and CaO and MgO is added at a combined quantity of 1.5% to 10% (all percentages by weight). Either one or both of these additives (CaO, MgO) is preferably in the form of fine grain, basic blast furnace slag, a mineral such as olevine, magnesite, diopside, horneblende or wollastonite. The grain size should not exceed 100 ~m. Prefer-ably the fireproof material containg no alkaline earth metal oxide other than CaO or MgO.
In another aspect the invention provides in a process of casting steel the improvement of using,as foundry runner bricks, bricks as defined above.
The material, in accordance with the invention, when used in foundry equipment for interfacing with molten steel, is positively intended to cause the hot steel to dissolve the fireproof material. The invention is based upon the surprising discovery that the deoxidizing products in the steel coact with the brick material in such a manner that, over the entire casting process, a liquid slag phase is formed in the brick-steel interface involving particularly the novel brick material and the dioxidizing . ..
- 2 -. ~ - , .
: ' , ~5;{~ 3 products. This slag phase is thus highly amenable to dissolve these deoxidizing products, and the resulting slag can easily be separated from the steel. In other words, the brick material is consumed to some extent on contact with molten steel and in such a manner that deoxidizing products in the steel become trapped in easily separable slag resulting from steel-brick interaction.
The following two examples illustrate the invention (all percentages by weight).
SiO2 - 67%
A~2 3 22%
CaO - 0-4%
MgO - 3%
Other Oxides (Tio2, Fe2O3, Na2O) ~ remainder This material has a softening point of 1420C, a melting point of 1480C, pressure-softening points To5 of 1185 C and T5 of 1275 C.
SiO2 - 61~
AQ2O3 - 20%
CaO - 6.3%
MgO - 0.1%
Other Oxides (Tio2, Fe2O3, Na2O) ~ remainder This material has a softening point of 1380C, a melting point of 1480 C, pressure-softening points To5 of 1130C and T5 of 1225C.
.
~:.
.
t ~5~323 This type of material is to be used as brick material in foundry work, particularly for lining runners and funnel tubes.
The invention is not limited to the embodiments described above; but all changes and modifications thereof, not constituting departures from the spirit and scope of the invention, are intended to be included.
~ ~ . ` . ' .
:
: ' , ~5;{~ 3 products. This slag phase is thus highly amenable to dissolve these deoxidizing products, and the resulting slag can easily be separated from the steel. In other words, the brick material is consumed to some extent on contact with molten steel and in such a manner that deoxidizing products in the steel become trapped in easily separable slag resulting from steel-brick interaction.
The following two examples illustrate the invention (all percentages by weight).
SiO2 - 67%
A~2 3 22%
CaO - 0-4%
MgO - 3%
Other Oxides (Tio2, Fe2O3, Na2O) ~ remainder This material has a softening point of 1420C, a melting point of 1480C, pressure-softening points To5 of 1185 C and T5 of 1275 C.
SiO2 - 61~
AQ2O3 - 20%
CaO - 6.3%
MgO - 0.1%
Other Oxides (Tio2, Fe2O3, Na2O) ~ remainder This material has a softening point of 1380C, a melting point of 1480 C, pressure-softening points To5 of 1130C and T5 of 1225C.
.
~:.
.
t ~5~323 This type of material is to be used as brick material in foundry work, particularly for lining runners and funnel tubes.
The invention is not limited to the embodiments described above; but all changes and modifications thereof, not constituting departures from the spirit and scope of the invention, are intended to be included.
~ ~ . ` . ' .
:
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A foundry brick suitable for use in contact with molten steel and formed of a fireproof material which comprises from 20 to 30% by weight of A12O3, from 60 to 70% by weight of SiO2 and from 1.5 to 10% by weight of an additive oxide which is CaO or MgO the composition of the brick being such that in use and in contact with molten steel the brick material will form a slag in which deoxidizing products in the steel dissolve and are thereby separated from the steel.
2. A foundry brick formed of a fireproof material and suitable for use in contact with molten steel in foundry equipment and having 20% to 30% of A12O3 and 60% to 70% of SiO2 and CaO and MgO at a combined content of 1.5% to 10%, each of them being present above the spurious level.
3. A foundry brick as claimed in claim 1 or 2, the CaO and MgO additives being provided in fine particulate form.
4. A foundry brick as claimed in claim 1 or 2, the grain being smaller than 100 µm.
5. A foundry brick as claimed in claim 1 or 2, wherein the additive oxide is added in the form of blast furnace slag, olivine, magnesite, diopside, horneblende or wollastonite.
6. A foundry brick as claimed in claim 1, which further comprises up to 10% of Tio2, Fe2O3 or Na2O.
7. A foundry brick as claimed in claim 1 or 2 wherein the fireproof material contains no alkaline earth metal oxide other than CaO or MgO.
8. In the process of casting steel the improvement which comprises using as foundry runner bricks bricks as claimed in claim 1 or 2.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19803008251 DE3008251C2 (en) | 1980-02-29 | 1980-02-29 | Refractory material for molten steel |
DEP3008251.0-45 | 1980-02-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1150323A true CA1150323A (en) | 1983-07-19 |
Family
ID=6096228
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA000371886A Expired CA1150323A (en) | 1980-02-29 | 1981-02-27 | Fireproof material for steel-casting foundry equipment |
Country Status (7)
Country | Link |
---|---|
JP (1) | JPS5914423B2 (en) |
AT (1) | AT376960B (en) |
BE (1) | BE887607A (en) |
CA (1) | CA1150323A (en) |
DE (1) | DE3008251C2 (en) |
FR (1) | FR2477136A1 (en) |
GB (1) | GB2070582B (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB9107223D0 (en) * | 1991-04-05 | 1991-05-22 | Foseco Holding Int Ltd | Filters for light metals |
DE4304724C1 (en) * | 1993-02-17 | 1994-05-05 | Metallgesellschaft Ag | Additive for strengthening oven refractory walls - comprises residues from titanium di:oxide prodn, coal residues, iron- and iron oxide-contg residues |
DE102007034426B3 (en) * | 2007-07-20 | 2008-12-04 | HAGENBURGER Feuerfeste Produkte für Gießereien und Stahlwerke KG | Component of a casting system through which a molten metal can flow |
CN115448736A (en) * | 2022-08-18 | 2022-12-09 | 四川贝金达新材料有限公司 | Runner brick resistant to corrosion of high-manganese, high-silicon and high-chromium alloy steel and preparation method thereof |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB601847A (en) * | 1944-10-10 | 1948-05-13 | Western Electric Co | Improvements in or relating to ceramic materials |
US3365318A (en) * | 1965-01-25 | 1968-01-23 | Harima Refractories Company Lt | Low temperature burned refractory brick and method of making the same |
GB1404956A (en) * | 1972-12-05 | 1975-09-03 | Le Abrazivny Z Ilich | Ceramic bonding material for abrasive tools |
-
1980
- 1980-02-29 DE DE19803008251 patent/DE3008251C2/en not_active Expired
- 1980-12-04 AT AT594180A patent/AT376960B/en not_active IP Right Cessation
-
1981
- 1981-02-16 FR FR8103002A patent/FR2477136A1/en active Granted
- 1981-02-20 BE BE0/203858A patent/BE887607A/en not_active IP Right Cessation
- 1981-02-26 JP JP56027565A patent/JPS5914423B2/en not_active Expired
- 1981-02-27 CA CA000371886A patent/CA1150323A/en not_active Expired
- 1981-03-02 GB GB8106532A patent/GB2070582B/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
AT376960B (en) | 1985-01-25 |
DE3008251C2 (en) | 1982-09-30 |
DE3008251B1 (en) | 1981-06-11 |
JPS56134559A (en) | 1981-10-21 |
FR2477136A1 (en) | 1981-09-04 |
BE887607A (en) | 1981-06-15 |
JPS5914423B2 (en) | 1984-04-04 |
GB2070582B (en) | 1983-06-02 |
FR2477136B1 (en) | 1984-04-13 |
GB2070582A (en) | 1981-09-09 |
ATA594180A (en) | 1984-06-15 |
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Legal Events
Date | Code | Title | Description |
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MKEX | Expiry |