US20100200424A1 - Plasma-electrolytic polishing of metals products - Google Patents
Plasma-electrolytic polishing of metals products Download PDFInfo
- Publication number
- US20100200424A1 US20100200424A1 US12/691,773 US69177310A US2010200424A1 US 20100200424 A1 US20100200424 A1 US 20100200424A1 US 69177310 A US69177310 A US 69177310A US 2010200424 A1 US2010200424 A1 US 2010200424A1
- Authority
- US
- United States
- Prior art keywords
- electrolyte
- voltage
- plasma
- electrolytic polishing
- products
- 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.)
- Abandoned
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 9
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 7
- 239000002184 metal Substances 0.000 title claims abstract description 7
- 150000002739 metals Chemical class 0.000 title abstract 2
- 239000003792 electrolyte Substances 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 5
- 230000006378 damage Effects 0.000 claims description 2
- 238000005265 energy consumption Methods 0.000 claims description 2
- 150000003839 salts Chemical class 0.000 claims description 2
- 238000007654 immersion Methods 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 claims 1
- 150000007522 mineralic acids Chemical class 0.000 claims 1
- 229910001069 Ti alloy Inorganic materials 0.000 abstract description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 7
- 235000011007 phosphoric acid Nutrition 0.000 description 4
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- DDFHBQSCUXNBSA-UHFFFAOYSA-N 5-(5-carboxythiophen-2-yl)thiophene-2-carboxylic acid Chemical compound S1C(C(=O)O)=CC=C1C1=CC=C(C(O)=O)S1 DDFHBQSCUXNBSA-UHFFFAOYSA-N 0.000 description 1
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 239000011532 electronic conductor Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 229920001451 polypropylene glycol Polymers 0.000 description 1
- AJPJDKMHJJGVTQ-UHFFFAOYSA-M sodium dihydrogen phosphate Chemical compound [Na+].OP(O)([O-])=O AJPJDKMHJJGVTQ-UHFFFAOYSA-M 0.000 description 1
- BAZAXWOYCMUHIX-UHFFFAOYSA-M sodium perchlorate Chemical compound [Na+].[O-]Cl(=O)(=O)=O BAZAXWOYCMUHIX-UHFFFAOYSA-M 0.000 description 1
- 229910001488 sodium perchlorate Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010936 titanium 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
- C25F3/18—Polishing of light metals
- C25F3/20—Polishing of light metals of aluminium
-
- 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
-
- 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
-
- 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
-
- 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
- C25F3/26—Polishing of heavy metals of refractory metals
Definitions
- Plasma-electrolytic polishing (PEP) of metal products was dicovered in 1986 [1]. The process is based on the smoothing of micro-roughness surfaces in a passage of current through ionized layer separating the electrolyte from the surface of the metal, with the application between a sufficiently high voltage (from 90 to 290 v). The voltage applied to the piece (+) and electronic conductor (cathode) immersed in the electrolyte ( ⁇ ). Steam layer is formed as a result of overheating electrolyte in contact with the surface of the product, above the point of boiling, Joule heat and abundant gas (the cathode), caused by the electrolysis of water.
- PEP Plasma-electrolytic polishing
- EPA has a significant advantage over the conventional process electrolytic polishing (EP), is the ability to use as the electrolyte harmless to human health, cheap and environmentally friendly solutions of low-concentration salts.
- EP electrolytic polishing
- polishing rate is proportional to the current density , as well as removal of metal in the PEP, as well as in PE is proportional to current density.
- Time tp inversely proportional to the speed of removing the metal and is directly proportional to voltage:
- Total Energy E is equal to multiplication of Ws by timing tp and is proportional to voltage U:
- Stainless steel type 400 and 300 may be polished in the electrolyte consisting of 70% solution of phosphoric acid in water 75 C temperature, voltage 48 V, current density 2-3 A/cm2. Polishing time 15-45 sec.
- Copper can be polished in a solution: 57% sodium phosphate (NaH2PO4)+9% H3PO4 (phosphoric acid) at a temperature of 70 C, with a voltage of 35 V, current density 8-9 A/cm2. Time polishing 2-10 sec.
- Products made of titanium alloy Ti, 6% Al, 4% V can be polished in the electrolyte consisting of 50% phosphoric acid, 10% Sodium perchlorate, 1% of hydrofluoric acid HF in the 75 C temperature, current density 1.5-2 A/cm2. Time 30-60 sec.
- Products made of aluminum alloy Al, 4% Cu, 0.9% Mn can be polished in a solution containing 50% polypropylene-glycol, 39% water, 10% Sulfuric acid, 2.5% Ammonium Fluoride, at 80 C temperature, voltage 80 V, current density 1.2-1.5 A/cm2. Polishing time 30-60 seconds.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
Abstract
Plasma-electrolytic polishing (PEP) of titanium alloy and other metals where plasma effect takes place when voltage does not exceed 80V DC.
Description
- Plasma-electrolytic polishing (PEP) of metal products was dicovered in 1986 [1]. The process is based on the smoothing of micro-roughness surfaces in a passage of current through ionized layer separating the electrolyte from the surface of the metal, with the application between a sufficiently high voltage (from 90 to 290 v). The voltage applied to the piece (+) and electronic conductor (cathode) immersed in the electrolyte (−). Steam layer is formed as a result of overheating electrolyte in contact with the surface of the product, above the point of boiling, Joule heat and abundant gas (the cathode), caused by the electrolysis of water. At the auxiliary electrode (cathode), which has a surface much more than surface processed products, ionized layer of steam is not occurs and the surface of the cathode in contact with the electrolyte. On boundary of the cathode to the electrolyte flow electrochemical reactions generally—the restoration of water to hydrogen gas:
-
2H2O+2e-=H2+2OH— - Later it was suggested to use more high voltage (200-400 V) for the sustainable maintenance of steam layer and its ionization [2]. EPA has a significant advantage over the conventional process electrolytic polishing (EP), is the ability to use as the electrolyte harmless to human health, cheap and environmentally friendly solutions of low-concentration salts. The disadvantages of EPA are:
- a) high energy, ten times more than energy PE; b) the high cost of equipment. The high cost of equipment due to high power PEP power supply and the need to ensure reliable electrical safety at high DC voltages.
- Studies of the EPA showed that in order to maintain stable Ionized steam layer (plasma) is needed some thermal power per unit area of treated surface WS.
- This power can be roughly estimated by the formula:
-
W s =i*U (1) - where i—current density on the treated surface, U—voltage between the product and the cathode. Formula (1) is approximate because the majority (80-90%) of voltage is lost by passing electrical current through the steam layer. The value of Ws depends on the composition of the material products of the electrolyte temperature and other factors, but remained within the 100-300 Wt/cm2. With increasing current density-voltage, under with the formula (1), decreases:
-
i=W s/U (2) - On the other hand, the polishing rate is proportional to the current density , as well as removal of metal in the PEP, as well as in PE is proportional to current density.
- Time tp, inversely proportional to the speed of removing the metal and is directly proportional to voltage:
-
t p =k*(U/W s) (3) - Total Energy E is equal to multiplication of Ws by timing tp and is proportional to voltage U:
-
E=t p *W s =kU (4) - Thus, to reduce the energy consumption of the process, it is necessary to reduce the operating voltage. This current density will grow in accordance with the formula (3).
- At the same time, reducing the voltage from hundreds of volts to values below 80V, sharply reduces the chance of injury of personnel of electric shocks and allows to simplify and reduce the price of equipment. Experience shows that the way to improve the PEP real, and the PEP at 80 and below can be practically implemented, which can be confirmed by a number of examples.
- Stainless steel type 400 and 300 may be polished in the electrolyte consisting of 70% solution of phosphoric acid in water 75 C temperature, voltage 48 V, current density 2-3 A/cm2. Polishing time 15-45 sec.
- Copper can be polished in a solution: 57% sodium phosphate (NaH2PO4)+9% H3PO4 (phosphoric acid) at a temperature of 70 C, with a voltage of 35 V, current density 8-9 A/cm2. Time polishing 2-10 sec.
- Products made of titanium alloy Ti, 6% Al, 4% V can be polished in the electrolyte consisting of 50% phosphoric acid, 10% Sodium perchlorate, 1% of hydrofluoric acid HF in the 75 C temperature, current density 1.5-2 A/cm2. Time 30-60 sec.
- Products made of aluminum alloy Al, 4% Cu, 0.9% Mn can be polished in a solution containing 50% polypropylene-glycol, 39% water, 10% Sulfuric acid, 2.5% Ammonium Fluoride, at 80 C temperature, voltage 80 V, current density 1.2-1.5 A/cm2. Polishing time 30-60 seconds.
-
- 1. Patent of German Democratic Republic (DD) #238074 (A1), Class 25F3/16, published Aug. 6, 1986
- 2. U.S. Pat. No. 5,028,304, Class B23H3/08, C25F3/16, C25F5/00, Published Feb. 7, 1991
Claims (3)
1. method of plasma electrolytic polishing surface metal products, including immersion in electrolyte, processed products and electro-conducting auxiliary electrode (cathode) and the application of permanent tension between manufacturing and product support electrode, only difference is that in order to reduce energy consumption and to avoid the risk of destruction of people with electric shocks, DC voltage does not exceed 80 V.
2. The method of claim 1 , characterized that as the electrolyte use water or water-organic solutions inorganic acids and their salts.
3. The method of claim 1 , characterized that the temperature of the electrolyte is in the interval from 20 to 100 C, mostly from 70 to 100 C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/691,773 US20100200424A1 (en) | 2009-02-09 | 2010-01-22 | Plasma-electrolytic polishing of metals products |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US15088109P | 2009-02-09 | 2009-02-09 | |
| US12/691,773 US20100200424A1 (en) | 2009-02-09 | 2010-01-22 | Plasma-electrolytic polishing of metals products |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US20100200424A1 true US20100200424A1 (en) | 2010-08-12 |
Family
ID=42539503
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US12/691,773 Abandoned US20100200424A1 (en) | 2009-02-09 | 2010-01-22 | Plasma-electrolytic polishing of metals products |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US20100200424A1 (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2495966C1 (en) * | 2012-07-03 | 2013-10-20 | Общество с ограниченной ответственностью "Научно-производственное предприятие "Уралавиаспецтехнология" | Method of grinding parts made from titanium alloys |
| WO2017060701A1 (en) | 2015-10-06 | 2017-04-13 | Wallwork Cambridge Limited | Smoothing the surface finish of rough metal articles |
| CN108875155A (en) * | 2018-05-29 | 2018-11-23 | 广东工业大学 | A kind of ceramic polishing machine energy consumption optimization method based on improved adaptive GA-IAGA |
| CN110948292A (en) * | 2019-12-13 | 2020-04-03 | 中山市奥博精密科技有限公司 | Polishing process of golf club head |
| CN111975000A (en) * | 2020-08-27 | 2020-11-24 | 西安理工大学 | Technology for 3D printing of complex parts by anisotropic polishing metal powder bed |
| KR102244502B1 (en) * | 2019-11-29 | 2021-04-27 | 한국생산기술연구원 | Cathode apparatus and method for plasma electrolytic polishing of inner surface of pipe |
| CN113564683A (en) * | 2021-09-02 | 2021-10-29 | 太原理工大学 | Electrolyte plasma polishing method for titanium alloy femoral stem prosthesis |
| CN114473649A (en) * | 2022-03-09 | 2022-05-13 | 江苏徐工工程机械研究院有限公司 | Electrolyte plasma polishing assembly and electrolyte plasma polishing device |
| WO2022151738A1 (en) * | 2021-01-13 | 2022-07-21 | 南京尚吉增材制造研究院有限公司 | Micro-nano bubble enhanced plasma polishing method |
| US11982011B2 (en) | 2018-05-22 | 2024-05-14 | Cummins Inc. | Plasma electrolytic polished diesel engine components |
| IT202300001221A1 (en) | 2023-01-27 | 2024-07-27 | Istituto Naz Fisica Nucleare | CHEMICAL SOLUTION CONTAINING PHOSPHORUS SUITABLE FOR POLISHING COPPER AND ITS ALLOYS BY PLASMA ELECTROPOLISHING |
| IT202300004173A1 (en) | 2023-03-07 | 2024-09-07 | Istituto Naz Fisica Nucleare | CHEMICAL SOLUTION CONTAINING SULPHAMIC ACID AND HYDROGEN PEROXIDE SUITABLE FOR POLISHING COPPER AND ITS ALLOYS BY PLASMA ELECTROPOLISHING |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2645611A (en) * | 1948-09-20 | 1953-07-14 | Shwayder Bros Inc | Method of and bath for electrolytic polishing |
| US3970529A (en) * | 1975-04-30 | 1976-07-20 | Oxy Metal Industries Corporation | Electropolishing aluminum and aluminum alloys |
| US6835300B2 (en) * | 2002-09-13 | 2004-12-28 | General Electric Company | Electropolishing solution and methods for its use and recovery |
| RU2355829C2 (en) * | 2007-04-25 | 2009-05-20 | ООО "НПП Уралавиаспецтехнология" | Method of electrolytic-plasma polishing of metals works |
-
2010
- 2010-01-22 US US12/691,773 patent/US20100200424A1/en not_active Abandoned
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2645611A (en) * | 1948-09-20 | 1953-07-14 | Shwayder Bros Inc | Method of and bath for electrolytic polishing |
| US3970529A (en) * | 1975-04-30 | 1976-07-20 | Oxy Metal Industries Corporation | Electropolishing aluminum and aluminum alloys |
| US6835300B2 (en) * | 2002-09-13 | 2004-12-28 | General Electric Company | Electropolishing solution and methods for its use and recovery |
| RU2355829C2 (en) * | 2007-04-25 | 2009-05-20 | ООО "НПП Уралавиаспецтехнология" | Method of electrolytic-plasma polishing of metals works |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2495966C1 (en) * | 2012-07-03 | 2013-10-20 | Общество с ограниченной ответственностью "Научно-производственное предприятие "Уралавиаспецтехнология" | Method of grinding parts made from titanium alloys |
| WO2017060701A1 (en) | 2015-10-06 | 2017-04-13 | Wallwork Cambridge Limited | Smoothing the surface finish of rough metal articles |
| US11982011B2 (en) | 2018-05-22 | 2024-05-14 | Cummins Inc. | Plasma electrolytic polished diesel engine components |
| US12606930B2 (en) | 2018-05-22 | 2026-04-21 | Cummins Inc. | Plasma electrolytic polished diesel engine components |
| CN108875155A (en) * | 2018-05-29 | 2018-11-23 | 广东工业大学 | A kind of ceramic polishing machine energy consumption optimization method based on improved adaptive GA-IAGA |
| KR102244502B1 (en) * | 2019-11-29 | 2021-04-27 | 한국생산기술연구원 | Cathode apparatus and method for plasma electrolytic polishing of inner surface of pipe |
| CN110948292A (en) * | 2019-12-13 | 2020-04-03 | 中山市奥博精密科技有限公司 | Polishing process of golf club head |
| CN111975000A (en) * | 2020-08-27 | 2020-11-24 | 西安理工大学 | Technology for 3D printing of complex parts by anisotropic polishing metal powder bed |
| WO2022151738A1 (en) * | 2021-01-13 | 2022-07-21 | 南京尚吉增材制造研究院有限公司 | Micro-nano bubble enhanced plasma polishing method |
| CN113564683A (en) * | 2021-09-02 | 2021-10-29 | 太原理工大学 | Electrolyte plasma polishing method for titanium alloy femoral stem prosthesis |
| CN114473649A (en) * | 2022-03-09 | 2022-05-13 | 江苏徐工工程机械研究院有限公司 | Electrolyte plasma polishing assembly and electrolyte plasma polishing device |
| IT202300001221A1 (en) | 2023-01-27 | 2024-07-27 | Istituto Naz Fisica Nucleare | CHEMICAL SOLUTION CONTAINING PHOSPHORUS SUITABLE FOR POLISHING COPPER AND ITS ALLOYS BY PLASMA ELECTROPOLISHING |
| IT202300004173A1 (en) | 2023-03-07 | 2024-09-07 | Istituto Naz Fisica Nucleare | CHEMICAL SOLUTION CONTAINING SULPHAMIC ACID AND HYDROGEN PEROXIDE SUITABLE FOR POLISHING COPPER AND ITS ALLOYS BY PLASMA ELECTROPOLISHING |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: RUSSAMER LAB, LLC, PENNSYLVANIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BERKOVICH, ANNA;MAYOROV, ALEXANDER;REEL/FRAME:030111/0971 Effective date: 20130319 |
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| STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |