US2493579A - Solution for anodic polishing of steel and iron articles - Google Patents
Solution for anodic polishing of steel and iron articles Download PDFInfo
- Publication number
- US2493579A US2493579A US733426A US73342647A US2493579A US 2493579 A US2493579 A US 2493579A US 733426 A US733426 A US 733426A US 73342647 A US73342647 A US 73342647A US 2493579 A US2493579 A US 2493579A
- Authority
- US
- United States
- Prior art keywords
- solution
- sulphate
- alkali metal
- steel
- iron
- 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
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims description 40
- 229910052742 iron Inorganic materials 0.000 title claims description 19
- 238000005498 polishing Methods 0.000 title claims description 14
- 229910000831 Steel Inorganic materials 0.000 title description 15
- 239000010959 steel Substances 0.000 title description 15
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 20
- 229910000318 alkali metal phosphate Inorganic materials 0.000 claims description 15
- 229910052936 alkali metal sulfate Inorganic materials 0.000 claims description 10
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 10
- DLYUQMMRRRQYAE-UHFFFAOYSA-N tetraphosphorus decaoxide Chemical compound O1P(O2)(=O)OP3(=O)OP1(=O)OP2(=O)O3 DLYUQMMRRRQYAE-UHFFFAOYSA-N 0.000 claims description 10
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 9
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims description 9
- 235000011130 ammonium sulphate Nutrition 0.000 claims description 9
- 229910021653 sulphate ion Inorganic materials 0.000 claims description 9
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims description 8
- 239000001166 ammonium sulphate Substances 0.000 claims description 8
- XLYOFNOQVPJJNP-PWCQTSIFSA-N Tritiated water Chemical compound [3H]O[3H] XLYOFNOQVPJJNP-PWCQTSIFSA-N 0.000 claims 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 22
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 12
- 239000001117 sulphuric acid Substances 0.000 description 12
- 235000011149 sulphuric acid Nutrition 0.000 description 12
- 229910052938 sodium sulfate Inorganic materials 0.000 description 11
- 235000011152 sodium sulphate Nutrition 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 239000001488 sodium phosphate Substances 0.000 description 7
- RYFMWSXOAZQYPI-UHFFFAOYSA-K trisodium phosphate Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])([O-])=O RYFMWSXOAZQYPI-UHFFFAOYSA-K 0.000 description 6
- 229910000406 trisodium phosphate Inorganic materials 0.000 description 6
- 235000019801 trisodium phosphate Nutrition 0.000 description 6
- 239000002253 acid Substances 0.000 description 4
- 150000001340 alkali metals Chemical class 0.000 description 3
- 239000008394 flocculating agent Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000005569 Iron sulphate Substances 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 2
- INHCSSUBVCNVSK-UHFFFAOYSA-L lithium sulfate Chemical compound [Li+].[Li+].[O-]S([O-])(=O)=O INHCSSUBVCNVSK-UHFFFAOYSA-L 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 241001408699 Artia Species 0.000 description 1
- 108010010803 Gelatin Proteins 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 229920000159 gelatin Polymers 0.000 description 1
- 239000008273 gelatin Substances 0.000 description 1
- 235000019322 gelatine Nutrition 0.000 description 1
- 235000011852 gelatine desserts Nutrition 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 description 1
- 229910052939 potassium sulfate Inorganic materials 0.000 description 1
- 239000001120 potassium sulphate Substances 0.000 description 1
- 235000011151 potassium sulphates Nutrition 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 229910000162 sodium phosphate Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F3/00—Electrolytic etching or polishing
- C25F3/16—Polishing
- C25F3/22—Polishing of heavy metals
- C25F3/24—Polishing of heavy metals of iron or steel
Definitions
- This invention relates to a solution for use in the anodic electrolytic polishing of steel and iron articles.
- the steel or iron artia red deposit is formed on the steel article.
- the solution also contain a small amount of sulphuric acid, 1. e., up to 4% by weight of the solution, but the sulphuric acid can be omitted provided there is sumcient alkali metal or ammonium sulphate present to maintain the iron in solution below the critical value.
- a preferred solution according to our invention is as follows, all percentages being by weight and in the case of the acids, we mean per cent by weight of 100% acid. course the acid employed need not be oi 100% strength but can be oi the strength commercially available.
- Range Preierred Percent Percent Phosphoric 'Acid 55 to 86 60 to 70 Sulphuric Acid 0. 1 to 4 1 to 4 Water 7 to 30 15 to 30 'lri-sodium Phosphate. l to 15 1 to 6 Sodium Sulphate at least 0. 5
- the sulphuric acid may be omitted entirely provided there is sufilcient sodium sulphate or its equivalent to maintain the'iron in solution below the critical value.
- the amount of sodium sulphate or its equivalent depends upon the amount of iron in solution. The solution will operate satisfactorily at the start of the process without any sodium sulphate or sulphuric acid, but after a time it is necessary to 'provide the sulphate ion required to cause precipitation of the iron thereby keeping the iron in solution below the critical value.
- the sodium sulphate shouldamount to at least 0.5% and it is preferred that the sodium sulphate be present in such amount as to saturate the bath and leave an excess of undissolved sodium sulphate in the solution. This excess acts as a reservoir for supplying the sulphate ion required for maintaining the iron in solution below the critical value.
- sulphuric acid is not essential, provided there is sumcient sodium sulphate or its equivalent present, the preferred solution contains some sulphuric acid but not over 4%.
- sodium sulphate we may employ other alkali metal or ammonium sulphates, for example, potassium sulphate, lithium sulphate and ammonium sulphate.
- the tri-sodium phosphate reduces the chemical attack of the solution on the article before current is applied and increases the polishing action after current is applied. In general, the amount of tri-sodium phosphate should be increased as the percentage of water in the solution increases. In place of tri-sodium phosphate, we
- the preferred bath contains about 0.5% of gelatin but amounts of flocculating agent'within the range of 0.1% to% maybeused.
- the solution may be used under widely varying conditions, the anode current density being as low as 25 or as high as 2000 amps. per square foot and the temperature can be any temperature up to about 250 F.
- the time it for polishing the steel will vary depending upon the polish required, from about 1 minute to 20 minutes, the usual period being about 5 minutes.
- a solution forruse in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode consisting essentially of and containing by weight 55 to 85% phosphoric acid, 7 to 30% water, 1 to of a member of the class consisting of tri-alkali metal phosphate, di-alkali metal phosphate, mono-alkali metal phosphate, and phosphorus pentoxide, and at least 0.5% of a sulphate of the class consisting of alkali metal sulphate and ammonium sulphate.
- a solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode consisting essentially of and containing by weight 55 to 85% phosphoric acid, 0.1% to 4% sulphuric acid, '7 to 30% water, 1 to 15% of a member of the class consisting oftri-alkali metal phosphate, di-alkali metal phosphate, mono-alkali metal phosphate,
- a solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 1% to 4% sulphuric acid, '7 to 30% water, 1 to 15% tri-sodium phosphate, and at least'0.5 of alkali metal sulphate.
- a solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode said solution consisting essentially of and containing by weight 55 to phosphoric acid, 0.1% to 4% sulphuric acid, '1 to" 30% water, 1 to 15% tri-sodium phosphate and at least 0.5 alkali metal sulphate.
- a solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 7 to 30% water, 1 to 15% of a member of the class consisting of tri-alkali metal phosphate, di+alkali metal phosphate, mono-alkali metal phosphate, and phosphorus pentoxide, and a sulphate of the class consisting of alkali metal sulphate and ammonium sulphate, said sulphate being present in amount sumcient to at least saturate the solution.
- a solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 0.1% to 4% sulphuric acid, 7 to 30% water, 1m 15% tri-sodium phosphate and alkali-metal sulphate in amount sufllcient to at least saturate the solution.
- a solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode consisting essentially of and containing by weight 55 to 85% phosphoric acid, 0.1% to 4% sulphuric acid, '7 to 30% water, 1 to'l5% of a member of the class consisting of tri-alkali metal phosphate, di-alkali metal phosphate, mono-alkali metal phosphate and phosphorus pentoxide, 0.1% to 5% of a flocculating agent for 'iron sulphate, and at least 0.5% of a sulphate of the class consisting of alkali metal sulphate and ammonium sulphate.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- ing And Chemical Polishing (AREA)
Description
Patented Jan. 3, 1950 UNITED STATES PATENT OFFICE sow'rros roa ANODIC rorlrsnme or s'rmu. AND mos narrows Milton B. Hammond, Edgeworth, and Glade B. Bowman, Coraopolis, 2a., assignora to Standard Steel Spring Company, Coraopoiia, Pa., a corporation oi Pennayl No Drawing. Application March 8, 1947, Serial No. 733.426
This invention relates to a solution for use in the anodic electrolytic polishing of steel and iron articles. In such processes the steel or iron artia red deposit is formed on the steel article. We
have found that by including sulphate ion in proper amount in a solution in which phosphoric acid is the principal constituent, we can cause the precipitation of iron sulphate from solution so as to maintain the concentration of iron in solution below a certain critical value such that the solution operates satisfactorily in polishing the steel. We have found that the iron metal in solution should be maintained below one ounce per gallon for satisfactory results.
In accordance with our invention, we include in a bath which consists principally of phosphoric acid, sodium sulphate or other alkali metal or ammonium sulphate in such amount as to react with the iron in solution and precipitate it and maintain the concentration of iron metal in solution below one ounce per gallon. It is pre-;
ferred that the solution also contain a small amount of sulphuric acid, 1. e., up to 4% by weight of the solution, but the sulphuric acid can be omitted provided there is sumcient alkali metal or ammonium sulphate present to maintain the iron in solution below the critical value.
A preferred solution according to our invention is as follows, all percentages being by weight and in the case of the acids, we mean per cent by weight of 100% acid. course the acid employed need not be oi 100% strength but can be oi the strength comercially available.
7 Claims. (Cl. 204-1405) 2 The solution may contain the ingredients within ranges as follows:
Range Preierred Percent Percent Phosphoric 'Acid 55 to 86 60 to 70 Sulphuric Acid 0. 1 to 4 1 to 4 Water 7 to 30 15 to 30 'lri-sodium Phosphate. l to 15 1 to 6 Sodium Sulphate at least 0. 5
As mentioned previously, the sulphuric acid may be omitted entirely provided there is sufilcient sodium sulphate or its equivalent to maintain the'iron in solution below the critical value. The amount of sodium sulphate or its equivalent depends upon the amount of iron in solution. The solution will operate satisfactorily at the start of the process without any sodium sulphate or sulphuric acid, but after a time it is necessary to 'provide the sulphate ion required to cause precipitation of the iron thereby keeping the iron in solution below the critical value. In general, the sodium sulphate shouldamount to at least 0.5% and it is preferred that the sodium sulphate be present in such amount as to saturate the bath and leave an excess of undissolved sodium sulphate in the solution. This excess acts as a reservoir for supplying the sulphate ion required for maintaining the iron in solution below the critical value. There is no upper limit to the amount of sodium sulphate which the bath may contain since it is desirableto have an excess in solid form.
While sulphuric acid is not essential, provided there is sumcient sodium sulphate or its equivalent present, the preferred solution contains some sulphuric acid but not over 4%.
In place of sodium sulphate, we may employ other alkali metal or ammonium sulphates, for example, potassium sulphate, lithium sulphate and ammonium sulphate.
The tri-sodium phosphate reduces the chemical attack of the solution on the article before current is applied and increases the polishing action after current is applied. In general, the amount of tri-sodium phosphate should be increased as the percentage of water in the solution increases. In place of tri-sodium phosphate, we
may use other tri-alkali phosphates, di-alkali or other suitable flocculating agent. The preferred bath contains about 0.5% of gelatin but amounts of flocculating agent'within the range of 0.1% to% maybeused.
In using the solution in the anodic polishing of steel, it is preferred to carry out the process at an anode current density of about 285 amps.
per square foot and at a temperature of about 190 F. However, the solution may be used under widely varying conditions, the anode current density being as low as 25 or as high as 2000 amps. per square foot and the temperature can be any temperature up to about 250 F. The time it for polishing the steel will vary depending upon the polish required, from about 1 minute to 20 minutes, the usual period being about 5 minutes.
The invention is not limited to th preferred ingredients or proportions but may be otherwise embodied or practiced within the scope of the following claims.
We claim: I
1. A solution forruse in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode, said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 7 to 30% water, 1 to of a member of the class consisting of tri-alkali metal phosphate, di-alkali metal phosphate, mono-alkali metal phosphate, and phosphorus pentoxide, and at least 0.5% of a sulphate of the class consisting of alkali metal sulphate and ammonium sulphate.
2. A solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode; said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 0.1% to 4% sulphuric acid, '7 to 30% water, 1 to 15% of a member of the class consisting oftri-alkali metal phosphate, di-alkali metal phosphate, mono-alkali metal phosphate,
and phosphorus pentoxide, and at least 0.5% of a sulphate of the classconsisting of alkali metal sulphate and ammonium sulphate.
3. A solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode, said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 1% to 4% sulphuric acid, '7 to 30% water, 1 to 15% tri-sodium phosphate, and at least'0.5 of alkali metal sulphate.
4. A solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode, said solution consisting essentially of and containing by weight 55 to phosphoric acid, 0.1% to 4% sulphuric acid, '1 to" 30% water, 1 to 15% tri-sodium phosphate and at least 0.5 alkali metal sulphate.
5. A solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode, said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 7 to 30% water, 1 to 15% of a member of the class consisting of tri-alkali metal phosphate, di+alkali metal phosphate, mono-alkali metal phosphate, and phosphorus pentoxide, and a sulphate of the class consisting of alkali metal sulphate and ammonium sulphate, said sulphate being present in amount sumcient to at least saturate the solution.
.6. A solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode, said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 0.1% to 4% sulphuric acid, 7 to 30% water, 1m 15% tri-sodium phosphate and alkali-metal sulphate in amount sufllcient to at least saturate the solution.
7. A solution for use in the electrolytic polishing of steel and iron articles wherein the article is employed as an anode, said solution consisting essentially of and containing by weight 55 to 85% phosphoric acid, 0.1% to 4% sulphuric acid, '7 to 30% water, 1 to'l5% of a member of the class consisting of tri-alkali metal phosphate, di-alkali metal phosphate, mono-alkali metal phosphate and phosphorus pentoxide, 0.1% to 5% of a flocculating agent for 'iron sulphate, and at least 0.5% of a sulphate of the class consisting of alkali metal sulphate and ammonium sulphate.
' NHLTON B. HAMMOND.
GLADE B. BOWMAN.
REFERENCES CITED The following references are of record in the flle of this patent:
UNITED STATES PATENTS Proceedings of The American Electroplaters Society, 1941, pages 109, 110.
Claims (1)
1. A SOLUTION FOR USE IN THE ELECTROLYTIC POLISHING OF STEEL AND IRON ARTICLES WHEREIN THE ARTICLE IS EMPLOYED AS AN ANODE, SAID SOLUTION CONSISTING ESSENTIALLY OF AND CONTAINING BY WEIGHT 55 TO 85% PHOSPHORIC ACID, 7 TO 30% WATER, 1 TO 15% OF A MEMBER OF THE CLASS CONSISTING OF TRI-ALKALI METAL PHOSPHATE, DI-ALKALI METAL PHOSPHATE, MONO-ALKALI METAL PHOSPHATE, AND PHOSPHORUS PENTOXIDE, AND AT LEAST 0.5% OF A SULPHATE OF THE CLASS CONSISTING OF ALKALI METAL SULPHATE AND AMMONIUM SULPHATE.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US733426A US2493579A (en) | 1947-03-08 | 1947-03-08 | Solution for anodic polishing of steel and iron articles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US733426A US2493579A (en) | 1947-03-08 | 1947-03-08 | Solution for anodic polishing of steel and iron articles |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2493579A true US2493579A (en) | 1950-01-03 |
Family
ID=24947539
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US733426A Expired - Lifetime US2493579A (en) | 1947-03-08 | 1947-03-08 | Solution for anodic polishing of steel and iron articles |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2493579A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3220887A (en) * | 1961-09-29 | 1965-11-30 | Exxon Research Engineering Co | Fuel cell electrolyte |
| US4935112A (en) * | 1988-04-07 | 1990-06-19 | Seneca Wire And Manufacturing Company | Continuous steel strand electrolytic processing |
| US5087342A (en) * | 1988-04-07 | 1992-02-11 | Seneca Wire And Manufacturing Company | Continuous steel strand electrolytic processing |
| US5380408A (en) * | 1991-05-15 | 1995-01-10 | Sandvik Ab | Etching process |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB521290A (en) * | 1937-11-15 | 1940-05-17 | Alais & Froges & Camarque Cie | Process for the treatment of surfaces consisting of aluminium or aluminium alloys |
| GB547592A (en) * | 1941-08-02 | 1942-09-02 | Vauxhall Motors Ltd | Improved electrocleaning baths |
| US2330170A (en) * | 1939-09-08 | 1943-09-21 | Crane Co | Electrolytic polishing of metal |
| GB556797A (en) * | 1943-02-05 | 1943-10-21 | Industrimetoder Ab | Process for electropolishing metal, especially articles of stainless steel |
-
1947
- 1947-03-08 US US733426A patent/US2493579A/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB521290A (en) * | 1937-11-15 | 1940-05-17 | Alais & Froges & Camarque Cie | Process for the treatment of surfaces consisting of aluminium or aluminium alloys |
| US2330170A (en) * | 1939-09-08 | 1943-09-21 | Crane Co | Electrolytic polishing of metal |
| GB547592A (en) * | 1941-08-02 | 1942-09-02 | Vauxhall Motors Ltd | Improved electrocleaning baths |
| GB556797A (en) * | 1943-02-05 | 1943-10-21 | Industrimetoder Ab | Process for electropolishing metal, especially articles of stainless steel |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3220887A (en) * | 1961-09-29 | 1965-11-30 | Exxon Research Engineering Co | Fuel cell electrolyte |
| US4935112A (en) * | 1988-04-07 | 1990-06-19 | Seneca Wire And Manufacturing Company | Continuous steel strand electrolytic processing |
| US5087342A (en) * | 1988-04-07 | 1992-02-11 | Seneca Wire And Manufacturing Company | Continuous steel strand electrolytic processing |
| US5380408A (en) * | 1991-05-15 | 1995-01-10 | Sandvik Ab | Etching process |
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