US3196056A - Methods for protecting furnace parts and the like - Google Patents
Methods for protecting furnace parts and the like Download PDFInfo
- Publication number
- US3196056A US3196056A US842620A US84262059A US3196056A US 3196056 A US3196056 A US 3196056A US 842620 A US842620 A US 842620A US 84262059 A US84262059 A US 84262059A US 3196056 A US3196056 A US 3196056A
- Authority
- US
- United States
- Prior art keywords
- parts
- metal
- metal parts
- coating
- furnace
- 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 - Lifetime
Links
- 238000000034 method Methods 0.000 title claims description 13
- 229910052751 metal Inorganic materials 0.000 claims description 27
- 239000002184 metal Substances 0.000 claims description 27
- 239000011248 coating agent Substances 0.000 claims description 15
- 238000000576 coating method Methods 0.000 claims description 15
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 10
- 239000003870 refractory metal Substances 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 8
- 229910044991 metal oxide Inorganic materials 0.000 claims description 8
- 150000004706 metal oxides Chemical class 0.000 claims description 8
- 150000002739 metals Chemical class 0.000 claims description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 7
- 229910002076 stabilized zirconia Inorganic materials 0.000 claims description 7
- 229910052782 aluminium Inorganic materials 0.000 claims description 6
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 10
- 229910052725 zinc Inorganic materials 0.000 description 10
- 239000011701 zinc Substances 0.000 description 10
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 6
- 239000012255 powdered metal Substances 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- XOOUIPVCVHRTMJ-UHFFFAOYSA-L zinc stearate Chemical compound [Zn+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O XOOUIPVCVHRTMJ-UHFFFAOYSA-L 0.000 description 3
- 238000007598 dipping method Methods 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000004663 powder metallurgy Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical group [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000007767 bonding agent Substances 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- BIJOYKCOMBZXAE-UHFFFAOYSA-N chromium iron nickel Chemical compound [Cr].[Fe].[Ni] BIJOYKCOMBZXAE-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005246 galvanizing Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910001026 inconel Inorganic materials 0.000 description 1
- UGKDIUIOSMUOAW-UHFFFAOYSA-N iron nickel Chemical compound [Fe].[Ni] UGKDIUIOSMUOAW-UHFFFAOYSA-N 0.000 description 1
- 239000011133 lead Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910001120 nichrome Inorganic materials 0.000 description 1
- 229910000623 nickel–chromium alloy Inorganic materials 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 239000011135 tin 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
- F27D1/16—Making or repairing linings ; Increasing the durability of linings; Breaking away linings
- F27D1/1678—Increasing the durability of linings; Means for protecting
- F27D1/1684—Increasing the durability of linings; Means for protecting by a special coating applied to the lining
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C24/00—Coating starting from inorganic powder
Definitions
- Example I In a furnace operating at approximately 1800 F. in the production of powdered metal articles formed with zinc stearate, I found that iron nickel chrome alloy shafts had a useful life of about two months. At the end of that time the shaft ends which were adjacent the bearing housings and therefore closer to the cold exterior of the furnace were corroded with zinc to the extent that they were no longer useful. I prepared a new set of shafts for this furnace of the same iron nickel chromium alloy but coated the shaft ends with a coating of stabilized zir- 31,196,955 Patented July 20, 1965 conia.
- Example II In the same furnace as Example I, I placed shafts coated with alumina as replacements for uncoated shafts.
- the alumina coated shafts were formed by coating the shafts with a thin coat of metallic aluminum and converting the aluminum in situ into alumina by heating in an oxidizing atmosphere.
- the alumina coated shafts show no signs of attack after six months use and are still in use. This means that they have at least 3 times the expected useful life of the uncoated parts.
- the coating can be applied not only by spraying the refractory metal oxide onto the surface and fusing as in Example I but may also be applied by dipping the part to be coated in a bath of the coating material and fusing, by dipping into the molten pure metal and oxidizing in situ as in Example II and by spraying with metal and oxidizing or by any other known method.
- the technique of this invention may be used in processes where molten zinc is used, for example, hold down parts and olls for galvanizing pots.
- the technique of this invention can be used for the protection of furnace parts for the purification of aluminum where the splash of molten hot aluminum striking the metal parts corrodes the parts.
- Nichrome undercoat in the form of a thin layer on the metal parts before applying the refractory metal oxide coating. This is particularly true where the coefiicient of expansion of the metal part is markedly different from that of the coating and the temperatures encountered are high. This is a matter in which men skilled in the art may use their own judgment.
- the improvement which comprises coating said metal parts with a refractory metal oxide selected from the group consisting of stabilized zirconia, aluminum and titania.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Coating By Spraying Or Casting (AREA)
Description
United States Patent 3,196,056 METHODS FOR PROTECTING FURNACE PARTS AND THE LIKE Martin N. Ornitz, Wilkinsburg, Pa., assignor to Blaw- Knox Company, Pittsburgh, Pa., a corporation of Delaware No Drawing. Filed Sept. 28, 1959, Ser. No. 842,620 4 Claims. (Cl. 148-126) This invention relates to methods for protecting furnace parts and the like and particularly to a method of protecting furnace parts and othe metal parts in which relatively volatile low melting metals or compounds of such metals are introduced or come into contact with such parts.
The problem of protectingfurnace parts against corrosion by volatilized low melting metals is faced by many segments of the metallurgical industry. One particular example hereafter specifically described is in the field of powder metallurgy. It is the practice in powder metallurgy to form articles from powdered metal in molds or dies which are lubricated and bonded by zinc stearate or similar metallic base lubricants and bonding agents. The articles produced by this practice are then treated in furnaces, the temperatures being in the neighborhood of 1475 to 2000 F. for ferrous parts. It is the general practice to place the articles in graphite trays, Inconel trays or similar trays resistant to high temperatures and to pass the trays through the treating furnace. However, this practice varies, and trays may or may not be used and the work may be passed on roller hearths, mesh conveyors or in various other ways. In passing the articles through the furnace, the zinc stearate volatilizes and the zinc utlimately deposits on the nearest cool surface. For example, the bearing shaft ends, the doors, door frames, wall supports and the like, are quickly coated with condensed zinc which rapidly corrodes the surface upon which it collects resulting in rapid, ultimate destruction. The condensed zinc is particularly damaging to roll shaft ends and the like so that these parts have a very short life and must be frequently replaced. This is obviously a serious problem and one which has remained unsolved until the present invention. I have discovered that this problem can be readily overcome and the life of rolls, shaft ends, door frames and the like greatly extended by the practice of my invention. I have discovered that by applying a coating of refractory metal oxide over the surfaces to be protected that this problem can be substantially solved. In a preferred practice, I find that by applying a coating of stabilized zirconia to the surface, I can substantially completely eliminate the corrosive effect of zinc in the furnaces Where zinc corrosion had previously been a very real problem. By stabilized zirconia, I mean zirconia which has been stabilized by the addition of calcium oxide or the like stabilizing agents. I have found that other refractory oxides, such as alumina and titania may similarly be used in substitution for stabilized zirconia in the practice of my invention.
The invention can perhaps best be understood by the following examples:
Example I In a furnace operating at approximately 1800 F. in the production of powdered metal articles formed with zinc stearate, I found that iron nickel chrome alloy shafts had a useful life of about two months. At the end of that time the shaft ends which were adjacent the bearing housings and therefore closer to the cold exterior of the furnace were corroded with zinc to the extent that they were no longer useful. I prepared a new set of shafts for this furnace of the same iron nickel chromium alloy but coated the shaft ends with a coating of stabilized zir- 31,196,955 Patented July 20, 1965 conia. This was accomplished by spraying the stabilized zirconia through a mctallizing gun onto the surfaces to be coated in the presence of a high temperature flame causing the zirconia to fuse into a thin film or coating over the parts to be protected. After eleven months of use in the same furnace environment the coated shafts show no signs of attack and are still in use. This means that the coated shafts have ta least 5 /2 times the useful life of the uncoated shafts.
Example II In the same furnace as Example I, I placed shafts coated with alumina as replacements for uncoated shafts. The alumina coated shafts were formed by coating the shafts with a thin coat of metallic aluminum and converting the aluminum in situ into alumina by heating in an oxidizing atmosphere. The alumina coated shafts show no signs of attack after six months use and are still in use. This means that they have at least 3 times the expected useful life of the uncoated parts.
Parts treated with other refractory metal oxides such as titania produce similar results.
I have found that the coating can be applied not only by spraying the refractory metal oxide onto the surface and fusing as in Example I but may also be applied by dipping the part to be coated in a bath of the coating material and fusing, by dipping into the molten pure metal and oxidizing in situ as in Example II and by spraying with metal and oxidizing or by any other known method.
In addition to treating parts for furnaces, I have found the technique of this invention may be used in processes where molten zinc is used, for example, hold down parts and olls for galvanizing pots.
Similarly the technique of this invention can be used for the protection of furnace parts for the purification of aluminum where the splash of molten hot aluminum striking the metal parts corrodes the parts.
I prefer to use stabilized zirconia as the coating material. However, it must be borne in mind that other refractory metal oxides could be substituted.
In the foregoing disclosure I have dealt with zinc and aluminum as the corrosive volatile metals. However, similar protection is offered against corrosion by other low volatile metals such as magnesium, sodium, lead and tin.
I prefer to apply a Nichrome undercoat in the form of a thin layer on the metal parts before applying the refractory metal oxide coating. This is particularly true where the coefiicient of expansion of the metal part is markedly different from that of the coating and the temperatures encountered are high. This is a matter in which men skilled in the art may use their own judgment.
I have set out certain preferred practices of my invention and certain preferred embodiments in the foregoing disclosure. However, it will be understood that this invention may be otherwise embodied within the scope of the following claims.
I claim:
1. In the process of treating materials at elevated temperatures in the presence of metal parts, which materials contain metals volatile at said elevated temperature and corrosive to the metal parts, the improvement which comprises coating said metal parts with a refractory metal oxide.
2. In the process of treating materials at elevated temperatures in the presence of metal parts, which materials contain metals volatile at said elevated temperature and corrosive to the metal parts, the improvement which comprises coating said metal parts with a refractory metal oxide selected from the group consisting of stabilized zirconia, aluminum and titania.
4 e: 3. In the process of treating powdered metal parts at oxide selected from the group consisting of stabilized elevated temperatures in the presence of metal furnace zirconia, alumina and titania.
parts, which powdered metal parts contain zinc volatile at the elevated temperature, the improvement which com- References Cited in file of this Patent prises coating said metal parts with a refractory metal 5 UNITED STATES PATENTS 1,852,162 Harris et a1. Apr. 5, 1932 4. In the process of treating powdered metal parts at 2,174 597 Pyster t 1 Oct 3, 1939 elevated temperatures in the presence of metal furnace 2,220,701 Benner et 1 Nov, 5, 1940 parts, which powdered metal parts contain zinc volatile 2,775,531 Montgomery et al Dec. 25, 1956 at the elevated temperature, the improvement which cOrn- 10 2,7 81,636 Brandes et a1. Feb. 19, 1957 prises coating Said metal parts With a refractory metal 2,824,794 Hathaway Feb. 25, 1958
Claims (1)
- 2. IN THE PROCESS OF TREATING MATERIALS AT ELEVATED TEMPERATURES IN THE PRESENCE OF METAL PARTS, WHICH MATERIALS CONTAIN METALS VOLATILE AT SAID ELEVATED TEMPERATURE AND CORROSIVE TO THE METAL PARTS, THE IMPROVEMENT WHICH COMPRISES COATING SAID METAL PARTS WITH REFRACTORY METAL OXIDE SELECTED FROM THE GROUP CONSISTING OF STABILIZED ZIRCONIA, ALUMINUM AND TITANIA.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US842620A US3196056A (en) | 1959-09-28 | 1959-09-28 | Methods for protecting furnace parts and the like |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US842620A US3196056A (en) | 1959-09-28 | 1959-09-28 | Methods for protecting furnace parts and the like |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3196056A true US3196056A (en) | 1965-07-20 |
Family
ID=25287829
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US842620A Expired - Lifetime US3196056A (en) | 1959-09-28 | 1959-09-28 | Methods for protecting furnace parts and the like |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3196056A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3455731A (en) * | 1966-02-25 | 1969-07-15 | Monsanto Res Corp | Heat-resistant coatings |
| US3836392A (en) * | 1971-07-07 | 1974-09-17 | Sandvik Ab | Process for increasing the resistance to wear of the surface of hard metal cemented carbide parts subject to wear |
| USRE32110E (en) * | 1971-05-26 | 1986-04-15 | General Electric Co. | Aluminum oxide coated cemented carbide product |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1852162A (en) * | 1929-03-08 | 1932-04-05 | Bell Telephone Labor Inc | Refining of copper |
| US2174597A (en) * | 1937-09-23 | 1939-10-03 | John N Pyster | Furnace wall and part thereof and method |
| US2220701A (en) * | 1937-03-20 | 1940-11-05 | Carborundum Co | Abrasion resistant furnace lining |
| US2775531A (en) * | 1949-05-10 | 1956-12-25 | Univ Ohio State Res Found | Method of coating a metal surface |
| US2781636A (en) * | 1952-06-23 | 1957-02-19 | Fulmer Res Inst Ltd | Low emissivity coatings for metal surfaces |
| US2824794A (en) * | 1954-05-18 | 1958-02-25 | Nat Lead Co | Process for fusion of high-melting metals |
-
1959
- 1959-09-28 US US842620A patent/US3196056A/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1852162A (en) * | 1929-03-08 | 1932-04-05 | Bell Telephone Labor Inc | Refining of copper |
| US2220701A (en) * | 1937-03-20 | 1940-11-05 | Carborundum Co | Abrasion resistant furnace lining |
| US2174597A (en) * | 1937-09-23 | 1939-10-03 | John N Pyster | Furnace wall and part thereof and method |
| US2775531A (en) * | 1949-05-10 | 1956-12-25 | Univ Ohio State Res Found | Method of coating a metal surface |
| US2781636A (en) * | 1952-06-23 | 1957-02-19 | Fulmer Res Inst Ltd | Low emissivity coatings for metal surfaces |
| US2824794A (en) * | 1954-05-18 | 1958-02-25 | Nat Lead Co | Process for fusion of high-melting metals |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3455731A (en) * | 1966-02-25 | 1969-07-15 | Monsanto Res Corp | Heat-resistant coatings |
| USRE32110E (en) * | 1971-05-26 | 1986-04-15 | General Electric Co. | Aluminum oxide coated cemented carbide product |
| US3836392A (en) * | 1971-07-07 | 1974-09-17 | Sandvik Ab | Process for increasing the resistance to wear of the surface of hard metal cemented carbide parts subject to wear |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: WHITE CONSOLIDATED INDUSTRIES, INC. Free format text: MERGER;ASSIGNORS:BLAW-KNOX COMPANY;KELVINATOR, INC.;WHITE-WESTINGHOUSE CORPORATION;AND OTHERS;REEL/FRAME:003926/0372 Effective date: 19781221 Owner name: BLAW-KNOX COMPANY Free format text: MERGER;ASSIGNORS:AETNA-STANDARD ENGINEERING COMPANY;BLAW-KNOX CONSTRUCTION EQUIPMENT, INC.,;BLAW-KNOX EQUIPMENT, INC.;AND OTHERS;REEL/FRAME:003926/0382 Effective date: 19781221 |