US3058841A - Method of coating ferrous articles with titanium - Google Patents
Method of coating ferrous articles with titanium Download PDFInfo
- Publication number
- US3058841A US3058841A US800112A US80011259A US3058841A US 3058841 A US3058841 A US 3058841A US 800112 A US800112 A US 800112A US 80011259 A US80011259 A US 80011259A US 3058841 A US3058841 A US 3058841A
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- US
- United States
- Prior art keywords
- titanium
- magnesium
- ferrous articles
- articles
- mixture
- 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.)
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- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims description 49
- 239000010936 titanium Substances 0.000 title claims description 46
- 229910052719 titanium Inorganic materials 0.000 title claims description 45
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 title claims description 29
- 238000000034 method Methods 0.000 title claims description 15
- 239000011248 coating agent Substances 0.000 title claims description 14
- 238000000576 coating method Methods 0.000 title claims description 14
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims description 44
- 239000011777 magnesium Substances 0.000 claims description 29
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 25
- 229910052749 magnesium Inorganic materials 0.000 claims description 25
- 229910001629 magnesium chloride Inorganic materials 0.000 claims description 22
- 239000000203 mixture Substances 0.000 claims description 17
- 229910052751 metal Inorganic materials 0.000 description 22
- 239000002184 metal Substances 0.000 description 22
- 238000006243 chemical reaction Methods 0.000 description 13
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 12
- 229910052742 iron Inorganic materials 0.000 description 6
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 6
- 229910052753 mercury Inorganic materials 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 239000007787 solid Substances 0.000 description 3
- 238000011282 treatment Methods 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 230000001464 adherent effect Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- -1 for example Substances 0.000 description 1
- 239000003870 refractory metal Substances 0.000 description 1
Images
Classifications
-
- 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
- C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
- C23C10/06—Solid state diffusion of only metal elements or silicon into metallic material surfaces using gases
- C23C10/08—Solid state diffusion of only metal elements or silicon into metallic material surfaces using gases only one element being diffused
- C23C10/10—Chromising
-
- 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
- C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
- C23C10/28—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
- C23C10/34—Embedding in a powder mixture, i.e. pack cementation
- C23C10/36—Embedding in a powder mixture, i.e. pack cementation only one element being diffused
Definitions
- This invention relates as indicated to the coating of ferrous articles with refractory metals, and more particularly, to the coating of iron and steel with titanium metal.
- a molten reducing agent for example, magnesium is reacted with titanium tetrachloride to form a metal titanium and the by-product magnesium chloride.
- the reaction between magnesium and titanium tetrachloride is ordinarily carried out in an iron reaction vessel.
- the titanium sponge formed on the side walls contains high amounts of iron, for example, 0.25 to 0.40% by weight. This is undoubtedly due to the contact between the titanium sponge and the clean reactor side wall.
- the present invention relates to a method of coating ferrous articles which comprises contacting the ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, and distilling said magnesium chloride and magnesium from said mixture.
- the single sheet of drawing is a flow sheet illustrating the process of the present invention.
- the ferrous articles to be treated include those formed of iron or mild steel.
- New equipment to be used in the Kroll process, for example, the reaction vessel, may be treated by the process herein disclosed, so as to reduce the iron contents in the titanium sponge.
- the reaction vessel to be treated is charged with magnesium, magnesium chloride and titanium metal. If ferrous articles are also to be treated they are placed in the reaction vessel.
- Sufficient titanium metal is added to the mixture to coat the articles to be treated. It will be apparent that the amount of titanium employed will be determined by the surface area of the ferrous articles to be treated.
- the ratio of magnesium chloride to titanium may be in the range from 2 to 7: 1, in parts by weight.
- the ratio of magnesium to titanium may be in the range from- 0.5 to 10:1, in parts by weight.
- the titanium metal preferably is in finely divided form, in order to obtain the highest efliciency of the treatment. Titanium of a particle size which will pass a US. mesh screen is satisfactory.
- the magnesium and magnesium chloride While the mixture is in contact with the ferrous articles, the magnesium and magnesium chloride are distilled there- "ice from, for example, at temperatures in excess of their boiling points at atmospheric pressures. If desired, it may be found desirable to distill the magnesium and magnesium chloride at reduced pressures.
- the titanium metal which is the residue of the distillation operation, is found as a tenacious coating on the ferrous articles.
- the process may be repeated several times, although a single treatment may be sufficient to accomplish the desired coating.
- the distillate of magnesium and magnesium chloride may be used in subsequent treatments, although it will be necessary to add titanium metal.
- Example I A new iron reaction vessel was charged with 2500 pounds of magnesium, to 200 pounds of magnesium chloride, and 30 to 40 pounds of titanium metal.
- the titanium metal had a particle size sufficiently small to pass 20 US. mesh screen.
- other ferrous articles to be coated with titanium were inserted in the vessel.
- the reaction vessel to be treated was placed in the hot furnace and the magnesium and magnesium chloride were distilled into a second vessel under reduced pressure of 100 microns of mercury. After distillation was completed, the reaction vessel was removed from the furnace and cooled. A black residue appeared on the interior surface of the reaction vessel, and the ferrous articles contained therein. The black residue was brushed off. The interior walls of the reaction vessel and the surfaces of the ferrous articles possessed a tough adherent coating of titanium metal.
- a method of coating ferrous articles with titanium which comprises contacting ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, and distilling said magnesium chloride and magnesium from said mixture at temperatures less than about 1000 C. with pressures less than about 100 microns of mercury.
- a method of coating ferrous articles with titanium which comprises contacting ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, said titanium metal having a small particle size, and distilling said magnesium chloride and magnesium from said mixture at temperatures less than about 1000 C. with pressures less than about 100 microns of mercury.
- a method of coating ferrous articles with titanium which comprises contacting ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, said titanium metal having a particle size which will pass 20 -U.S. mesh screen, and distilling said magnesium chloride and magnesium. from. said mixture at temperatures less than about 1000" C. with pressuresiless,thaniabout 100 microns of mercury.
- a method of coating ferrous articles with titanium which comprises contacting ferrous articles witha .mixture ofmagnesium chloride, magnesium, and titanium metal, said titanium metal having a small particle size, and while'said mixture is .in contact with said errous articles distilling said magnesium chloride and magnesium therefrom at temperature less than about 1000? C. with pressures less than about 100 microns'of mercury.
- a method ofcoating-ferrous articles with titanium which comprisescontacting ferrous articles with a mixture of magnesium chloride, magnesium,.and :titanium metal, I
- said titanium being present in said mixture in amounts at least suflicient to coat the surface of the ferrous articles to be treated, said magnesium chloride and magnesium being present in amounts at least equimolecular to said titanium, said titanium metal-having a small particle size, and distilling said magnesium chloride and magnesium from said mixture at temperatures less than about 1000" C. with pressures less than about 100 microns of mercury.
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture And Refinement Of Metals (AREA)
Description
Oct. 16, 1962 F, 'w. DROSTEN EI'AL 3,058,841
METHOD OF COATING FERROUS ARTICLES WITH TITANIUM Filed March 18, 1959 TL M cz I y (soua) m/0) (sa a) HEH T nj Mg 02 9 6000) (L/OU/D) 0.1au10) p/ammr/a/v UNDER REDUCED HQE55URE5 Fmnaw ARTICLE 60/? T50 FER/7005 ART/GL5 United States Patent 3,058,841 METHOD OF COATING F RROUS ARTICLES WITH TITANIUM Fred W. Drosten, Chattanooga, Stanley V. Weglarz, Nashville, and Robert C. Robinson, Chattanooga, Tenn., assignors, by mesne assignments, of one-half to Republic Steel Corporation, Cleveland, Ohio, a corporation of New Jersey, and one-half to Vrtro Corporation of America, a corporation of Delaware Filed Mar. 18, 1959, Ser. No. 800,112 5 Claims. (Cl. 117-102) This invention relates as indicated to the coating of ferrous articles with refractory metals, and more particularly, to the coating of iron and steel with titanium metal.
In the production of titanium by the process generally known as the Krollprocess, described in U.S. Patent No. 2,205,854, a molten reducing agent, for example, magnesium is reacted with titanium tetrachloride to form a metal titanium and the by-product magnesium chloride. The reaction between magnesium and titanium tetrachloride is ordinarily carried out in an iron reaction vessel.
If the reaction vessel is new, the titanium sponge formed on the side walls, in most instances, contains high amounts of iron, for example, 0.25 to 0.40% by weight. This is undoubtedly due to the contact between the titanium sponge and the clean reactor side wall.
It is often desired to coat ferrous articles with titanium for various uses, for instance, in addition to reactor vessels, it may be desirable to employ various devices in association with the titanium sponge during the various steps in the manufacture of the titanium metal. Contamination of the titanium might be prevented, if these various devices have been previously plated with a layer of titamum.
It is, therefore, an object of the present invention to coat ferrous articles with metal. It is another object of the invention to treat various ferrous articles, so as to reduce the contamination of titanium metal contacted thereby. Further objects and advantages of this invention will become evi ent as the description proceeds.
Briefly stated, the present invention relates to a method of coating ferrous articles which comprises contacting the ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, and distilling said magnesium chloride and magnesium from said mixture.
The single sheet of drawing is a flow sheet illustrating the process of the present invention.
The ferrous articles to be treated include those formed of iron or mild steel. New equipment to be used in the Kroll process, for example, the reaction vessel, may be treated by the process herein disclosed, so as to reduce the iron contents in the titanium sponge.
The reaction vessel to be treated is charged with magnesium, magnesium chloride and titanium metal. If ferrous articles are also to be treated they are placed in the reaction vessel.
Sufficient titanium metal is added to the mixture to coat the articles to be treated. It will be apparent that the amount of titanium employed will be determined by the surface area of the ferrous articles to be treated.
The ratio of magnesium chloride to titanium may be in the range from 2 to 7: 1, in parts by weight. The ratio of magnesium to titanium may be in the range from- 0.5 to 10:1, in parts by weight. These ratios have been found satisfactory; however, it will be obvious that they may be varied.
The titanium metal preferably is in finely divided form, in order to obtain the highest efliciency of the treatment. Titanium of a particle size which will pass a US. mesh screen is satisfactory.
While the mixture is in contact with the ferrous articles, the magnesium and magnesium chloride are distilled there- "ice from, for example, at temperatures in excess of their boiling points at atmospheric pressures. If desired, it may be found desirable to distill the magnesium and magnesium chloride at reduced pressures.
The titanium metal, which is the residue of the distillation operation, is found as a tenacious coating on the ferrous articles.
The process may be repeated several times, although a single treatment may be sufficient to accomplish the desired coating. The distillate of magnesium and magnesium chloride may be used in subsequent treatments, although it will be necessary to add titanium metal.
In order to further understand the invention the following example is given. It is intended, however, that the example is merely by way of illustration and is not intended to limit the invention.
Example I A new iron reaction vessel was charged with 2500 pounds of magnesium, to 200 pounds of magnesium chloride, and 30 to 40 pounds of titanium metal. The titanium metal had a particle size sufficiently small to pass 20 US. mesh screen. In addition, other ferrous articles to be coated with titanium were inserted in the vessel.
The reaction vessel to be treated was placed in the hot furnace and the magnesium and magnesium chloride were distilled into a second vessel under reduced pressure of 100 microns of mercury. After distillation was completed, the reaction vessel was removed from the furnace and cooled. A black residue appeared on the interior surface of the reaction vessel, and the ferrous articles contained therein. The black residue was brushed off. The interior walls of the reaction vessel and the surfaces of the ferrous articles possessed a tough adherent coating of titanium metal.
The mechanism by which the ferrous articles are coated with titanium is not definitely known. The following theory is presented merely as an aid to understanding the invention. It should not be considered as a restriction on the invention. It is believed that the titanium formed on the articles may be by the following reactions:
less than 100 microns pressure and the subsequent reaction with magnesium on the side wall of the reactor to deposit the titanium.
less than 100 microns pressure Ti-F e (solid alloy) Mg 012 (gas) principle of the invention Ti (solid) MgCh (gas) T1012 (gas) Mg (gas) F e (solid) Mg (gas) TiO h (gas) Other modes of applying the may be employed, change being made as regards the tails described, provided the features stated in any of the following claims or the equivalent of such be employed.
We, therefore, particularly point out and distinctly claim as our invention:
1. A method of coating ferrous articles with titanium which comprises contacting ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, and distilling said magnesium chloride and magnesium from said mixture at temperatures less than about 1000 C. with pressures less than about 100 microns of mercury.
2. A method of coating ferrous articles with titanium which comprises contacting ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, said titanium metal having a small particle size, and distilling said magnesium chloride and magnesium from said mixture at temperatures less than about 1000 C. with pressures less than about 100 microns of mercury.
3. A method of coating ferrous articles with titanium which comprises contacting ferrous articles with a mixture of magnesium chloride, magnesium, and titanium metal, said titanium metal having a particle size which will pass 20 -U.S. mesh screen, and distilling said magnesium chloride and magnesium. from. said mixture at temperatures less than about 1000" C. with pressuresiless,thaniabout 100 microns of mercury.
4. A method of coating ferrous articles with titanium which comprises contacting ferrous articles witha .mixture ofmagnesium chloride, magnesium, and titanium metal, said titanium metal having a small particle size, and while'said mixture is .in contact with said errous articles distilling said magnesium chloride and magnesium therefrom at temperature less than about 1000? C. with pressures less than about 100 microns'of mercury.
5. A method ofcoating-ferrous articles with titanium which comprisescontacting ferrous articles with a mixture of magnesium chloride, magnesium,.and :titanium metal, I
said titanium being present in said mixture in amounts at least suflicient to coat the surface of the ferrous articles to be treated, said magnesium chloride and magnesium being present in amounts at least equimolecular to said titanium, said titanium metal-having a small particle size, and distilling said magnesium chloride and magnesium from said mixture at temperatures less than about 1000" C. with pressures less than about 100 microns of mercury.
References Cited in the file of this patent UNITED STATES PATENTS 2,205,854. Kroll June 25, 1940 2,706,153 Glasser Apr. 12, 1955 2,732,321 Gill et 1. Jan. 24, 1956 FQREIGN PATENTS 7 141,999 Australia Jan. 15, 1948
Claims (1)
1. A METHOD OF COATING FERROUS ARTICLES WITH TITANIUM WHICH COMPRISES CONTSCTING FERROUS ARTICLES WITH A MIXTURE OF MAGNESIUM CHLORIDE, MAGNESIUM AND TITANIUM METAL, AND DISTILLING SAID MAGNESIUM CHLORIDE AND MAGNESIUM FROM SAID MIXTURE AT TEMPARETURE LESS THAN ABOUT 1000*C. WITH PRESSURE THAN ABOUT 100 MICRONS OF MERCURY.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US800112A US3058841A (en) | 1959-03-18 | 1959-03-18 | Method of coating ferrous articles with titanium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US800112A US3058841A (en) | 1959-03-18 | 1959-03-18 | Method of coating ferrous articles with titanium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3058841A true US3058841A (en) | 1962-10-16 |
Family
ID=25177515
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US800112A Expired - Lifetime US3058841A (en) | 1959-03-18 | 1959-03-18 | Method of coating ferrous articles with titanium |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3058841A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3184331A (en) * | 1963-12-16 | 1965-05-18 | Du Pont | Process of diffusion coating |
| US3184330A (en) * | 1963-03-28 | 1965-05-18 | Du Pont | Diffusion process |
| US3627594A (en) * | 1967-12-12 | 1971-12-14 | Yawata Iron & Steel Co | Method of forming electric insulating films on oriented silicon steel |
| US4196022A (en) * | 1976-12-21 | 1980-04-01 | Pioneer Electronic Corporation | Surface hardening method |
| JP2014214356A (en) * | 2013-04-26 | 2014-11-17 | 株式会社大阪チタニウムテクノロジーズ | Method for producing high melting point metal |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2205854A (en) * | 1937-07-10 | 1940-06-25 | Kroll Wilhelm | Method for manufacturing titanium and alloys thereof |
| US2706153A (en) * | 1951-04-19 | 1955-04-12 | Kennecott Copper Corp | Method for the recovery of titanium |
| US2732321A (en) * | 1956-01-24 | Plating processes and compositions |
-
1959
- 1959-03-18 US US800112A patent/US3058841A/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2732321A (en) * | 1956-01-24 | Plating processes and compositions | ||
| US2205854A (en) * | 1937-07-10 | 1940-06-25 | Kroll Wilhelm | Method for manufacturing titanium and alloys thereof |
| US2706153A (en) * | 1951-04-19 | 1955-04-12 | Kennecott Copper Corp | Method for the recovery of titanium |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3184330A (en) * | 1963-03-28 | 1965-05-18 | Du Pont | Diffusion process |
| US3184331A (en) * | 1963-12-16 | 1965-05-18 | Du Pont | Process of diffusion coating |
| US3627594A (en) * | 1967-12-12 | 1971-12-14 | Yawata Iron & Steel Co | Method of forming electric insulating films on oriented silicon steel |
| US4196022A (en) * | 1976-12-21 | 1980-04-01 | Pioneer Electronic Corporation | Surface hardening method |
| JP2014214356A (en) * | 2013-04-26 | 2014-11-17 | 株式会社大阪チタニウムテクノロジーズ | Method for producing high melting point metal |
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