US1975818A - Coating for pistons - Google Patents

Coating for pistons Download PDF

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Publication number
US1975818A
US1975818A US630245A US63024532A US1975818A US 1975818 A US1975818 A US 1975818A US 630245 A US630245 A US 630245A US 63024532 A US63024532 A US 63024532A US 1975818 A US1975818 A US 1975818A
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US
United States
Prior art keywords
coating
tin
piston
pistons
nickel
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
Application number
US630245A
Inventor
Harold K Work
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Howmet Aerospace Inc
Original Assignee
Aluminum Company of America
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Aluminum Company of America filed Critical Aluminum Company of America
Priority to US630245A priority Critical patent/US1975818A/en
Application granted granted Critical
Publication of US1975818A publication Critical patent/US1975818A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00—Electroplating characterised by the article coated
    • C25D7/10—Bearings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49229—Prime mover or fluid pump making
    • Y10T29/49249—Piston making
    • Y10T29/49256—Piston making with assembly or composite article making
    • Y10T29/49263—Piston making with assembly or composite article making by coating or cladding
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12708—Sn-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12708—Sn-base component
    • Y10T428/12722—Next to Group VIII metal-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12736—Al-base component
    • Y10T428/1275—Next to Group VIII or IB metal-base component

Definitions

  • the invention relates to a method of applying a permanent and wear-resisting coating on pistons for internal combustion engines or the like.
  • Pistons made from aluminum alloys or other light metals and alloys are now in use in large numbers. Unless properly andcarefully designed and lubricated these light alloy pistons have a tendency to wear slightly more than pistons of the harder and heavier metals, but by reason of m the many advantages attendant on their use,
  • the present invention has for its purpose the coating of an aluminum alloy piston with tin by a method whereby a permanent bond is established between the metal of the piston and the coating metal.
  • This I have accomplished by applying to the piston an intermediate coating of a harder metal, such as nickel,and then superimposing a coating of tin. over the harder metal.
  • a coating of tin applied in this way is quite permanent, having no tendency to scale off or scuff.
  • the double coating is preferably applied electrolytically and I have found the following to be ⁇ w a satisfactory course of procedure, although other methods of coating may be employed. I first clean the machined. piston in a mild alkaline cleaner made up of about equal parts of sodium carbonate and trisodium phosphate of a concentration of approximately one to three ounces total in a gallon of water. This procedure removes any possible traces of oil or any type of organic solvent. This bath will function best at about 200 Fahrenheit and the cleaning operation should be followed by a cold water rinse.
  • the piston surface may now be roughened by dipping in a solution of the following composition:
  • Nitric acid (HNOa) (Sp. Gr. 1.42) 3 parts 65 Hydrofiuoric acid (HF) (48-52%) 1 part be varied depending on the material to be plated each day.
  • Nickel sulfate NiSO4 71120 19 oz. per gal. water
  • Magnesium sulfate MgSO4 71-120) l0 oz.per gal. water
  • Ammonium chloride (NH4C1) 2 oz. per gal. water Boric acid (HaBOa) 202. per gal. water
  • the current density employed should be in the order of 15 amperes per square foot but this may and the plating speed. At 15 amperes per square 5 foot a thicknessof slightly under a thousandth (.001) of an inch of nickel per hour is obtained.
  • the nickel coating should be 0.0003 inch or more in thickness. I believe that the function of the nickel or other hard metal, such as, for instance, chromium or cobalt, is to anchor itself into the minute pits etched out by the dipping solution and thus serve as a solid foundation to whichthe coating of tin adheres much more readily than to the aluminum itself.
  • a final coating of tin is superimposed upon the nickel by any standard method such as by electrodeposition from a bath containing 2 to 3 per cent stannous chloride, 5.5 to 6.5 per cent ammonium oxalate and 0.3 to 0.4 per cent oxalic acidusing a current density of about 3.6 amperes per square foot.
  • a coating of about 0.0004 inch of tin over nickel gives highly satisfactory results.
  • the tin coating may be made thicker or thinner than this figure, depending on service requirements or the demands of the manufacturer or customer.
  • a method of improving the bearing surface of alight alloy piston which consists in applying upon said piston a coating of a metal selected from the group comprising nickel, chromium and cobalt, and superimposing upon said coating an additional outer coating of tin.
  • a method of applying upon an aluminum base alloy piston a coating of tin which consists in applying a coating of nickel intermediate the surface of said piston and the tin coating.
  • a method of producing an aluminum base alloy piston characterized by a long service life and good bearing properties which consists in first electroplating upon said piston a coating of nickel more than 0.0003 inch in thickness, then electroplating upon said nickel a coating of tin.
  • a method of producing an aluminum base alloy piston characterized by a long service life and good bearing properties which consists in first machining the piston, then cleaning the piston surface with a mild alkaline cleaner, then roughening said cleaned surface by dipping the piston in a corrosive'solution, then electroplating upon said roughened surface a coating of a metal selected from the group comprising nickel, chromium and cobalt, and then electroplating upon said coating a coating of tin.
  • a method of producing an aluminum base alloy piston characterized by a long service life and good bearing properties which consists in first applying upon said piston a coating of a metal selected from the group comprising nickel, chromium and cobalt, then electroplating upon said-coating a coating of tin.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electroplating Methods And Accessories (AREA)

Description

Patented Oct. 9, 1934 UNITED STATES PATENT OFFICE COATING FOR PISTONS No Drawing. Application August 24, 1932, Serial No. 630,245
Claims.
' The invention relates to a method of applying a permanent and wear-resisting coating on pistons for internal combustion engines or the like.
Pistons made from aluminum alloys or other light metals and alloys are now in use in large numbers. Unless properly andcarefully designed and lubricated these light alloy pistons have a tendency to wear slightly more than pistons of the harder and heavier metals, but by reason of m the many advantages attendant on their use,
structural and design methods have been developed which, to some extent, lessen or compensate for the tendency to wear.
It is the purpose of the present invention to provide a method whereby the wear-resisting and bearing properties of light alloy pistons may be greatly improved.
I Attempts have heretofore been made to apply coatings of tin to aluminum alloy pistons but a coating sufiiciently adherent to withstand for a satisfactory period of time the conditions existing in a cylinder of an internal combustion engine in operation was not obtained and efforts to use tincoated aluminum base alloy pistons have met but with temporary success.
The present invention has for its purpose the coating of an aluminum alloy piston with tin by a method whereby a permanent bond is established between the metal of the piston and the coating metal. This I have accomplished by applying to the piston an intermediate coating of a harder metal, such as nickel,and then superimposing a coating of tin. over the harder metal. I have found that a coating of tin applied in this way is quite permanent, having no tendency to scale off or scuff.
The double coating is preferably applied electrolytically and I have found the following to be {w a satisfactory course of procedure, although other methods of coating may be employed. I first clean the machined. piston in a mild alkaline cleaner made up of about equal parts of sodium carbonate and trisodium phosphate of a concentration of approximately one to three ounces total in a gallon of water. This procedure removes any possible traces of oil or any type of organic solvent. This bath will function best at about 200 Fahrenheit and the cleaning operation should be followed by a cold water rinse.
The piston surface may now be roughened by dipping in a solution of the following composition:
Nitric acid (HNOa) (Sp. Gr. 1.42) 3 parts 65 Hydrofiuoric acid (HF) (48-52%) 1 part be varied depending on the material to be plated each day.
Nickel sulfate (NiSO4 71120) 19 oz. per gal. water Magnesium sulfate (MgSO4 71-120) l0 oz.per gal. water Ammonium chloride (NH4C1) 2 oz. per gal. water Boric acid (HaBOa) 202. per gal. water The current density employed should be in the order of 15 amperes per square foot but this may and the plating speed. At 15 amperes per square 5 foot a thicknessof slightly under a thousandth (.001) of an inch of nickel per hour is obtained.
For the best results the nickel coating should be 0.0003 inch or more in thickness. I believe that the function of the nickel or other hard metal, such as, for instance, chromium or cobalt, is to anchor itself into the minute pits etched out by the dipping solution and thus serve as a solid foundation to whichthe coating of tin adheres much more readily than to the aluminum itself.
A final coating of tin is superimposed upon the nickel by any standard method such as by electrodeposition from a bath containing 2 to 3 per cent stannous chloride, 5.5 to 6.5 per cent ammonium oxalate and 0.3 to 0.4 per cent oxalic acidusing a current density of about 3.6 amperes per square foot. I have found that a coating of about 0.0004 inch of tin over nickel gives highly satisfactory results. The tin coating may be made thicker or thinner than this figure, depending on service requirements or the demands of the manufacturer or customer.
A number of tests were run in a commercial eight cylinder engine for the purpose of comparing different coating combinations. All tests' were run for about two months in a motor which ran intermittently, starting cold at least twice A piston plated with 0.0004 inch of tin directly on aluminum was scuffed on the maximum thrust side and the plated surface was non-uniform.
Unplated aluminum pistons simultaneously running in the same engine were slightly scuffed.
In these last three pistons there were no signs of smiling, spotting, or irregularity in the bearing surface.
I have determined that this double coating on an aluminum or aluminum-base alloy piston, consisting of a coating of tin superimposed upon a harder metal over the aluminum, forms the best possible combination. It combines to some extent the advantages of a hard metal and a soft metal, exhibiting simultaneously the properties of adhesiveness, tenacity, and good bearing properties. In its broadest aspect my invention contemplates a combination coating of a'soft metal and a hard metal so chosen that there will be present at the same time a good bearing surface and an adherent coating but I specifically prefer to use a combination coating composed of an intermediate nickel layer and an outer tin layer.
Having thus described my invention, I claim:
1. A method of improving the bearing surface of alight alloy piston which consists in applying upon said piston a coating of a metal selected from the group comprising nickel, chromium and cobalt, and superimposing upon said coating an additional outer coating of tin.
2. A method of applying upon an aluminum base alloy piston a coating of tin which consists in applying a coating of nickel intermediate the surface of said piston and the tin coating.
3. A method of producing an aluminum base alloy piston characterized by a long service life and good bearing properties which consists in first electroplating upon said piston a coating of nickel more than 0.0003 inch in thickness, then electroplating upon said nickel a coating of tin.
4. A method of producing an aluminum base alloy piston characterized by a long service life and good bearing properties which consists in first machining the piston, then cleaning the piston surface with a mild alkaline cleaner, then roughening said cleaned surface by dipping the piston in a corrosive'solution, then electroplating upon said roughened surface a coating of a metal selected from the group comprising nickel, chromium and cobalt, and then electroplating upon said coating a coating of tin.
5. A method of producing an aluminum base alloy piston characterized by a long service life and good bearing properties which consists in first applying upon said piston a coating of a metal selected from the group comprising nickel, chromium and cobalt, then electroplating upon said-coating a coating of tin.
HAROLD K. WORK.
US630245A 1932-08-24 1932-08-24 Coating for pistons Expired - Lifetime US1975818A (en)

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Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2505776A (en) * 1941-07-11 1950-05-02 Shelley Method of manufacture of hollow floats of thin metal for ship compasses
US2509117A (en) * 1946-07-24 1950-05-23 Us Rubber Co Method of making composite wire
US2575214A (en) * 1948-09-30 1951-11-13 Wright Aeronautical Corp Piston with plated piston ring grooves
US2611163A (en) * 1947-08-20 1952-09-23 Cleveland Graphite Bronze Co Method of making bearings
DE897786C (en) * 1951-03-16 1953-11-23 Mahle Kg Pairs of machine parts made of light metal sliding on each other and processes for their production
US2682702A (en) * 1949-04-06 1954-07-06 Ohio Commw Eng Co Carbonyl metal plated product
US2704512A (en) * 1951-12-12 1955-03-22 Metal printing plate and method of
US2761792A (en) * 1952-06-13 1956-09-04 Eutectic Welding Alloys Process for preparing aluminum cables for soldering
US2766195A (en) * 1953-01-26 1956-10-09 American Brake Shoe Co Plated aluminum bearings
DE969934C (en) * 1943-07-25 1958-07-31 Messerschmitt Boelkow Blohm Composite metal pistons
US2854737A (en) * 1945-01-06 1958-10-07 Allen G Gray Copper coated uranium article
US2854738A (en) * 1945-01-09 1958-10-07 Allen G Gray Nickel coated uranium article
US2894885A (en) * 1945-01-06 1959-07-14 Allen G Gray Method of applying copper coatings to uranium
US2894884A (en) * 1945-01-09 1959-07-14 Allen G Gray Method of applying nickel coatings on uranium
US2933421A (en) * 1949-03-21 1960-04-19 Herbert H Hyman Dissolution method of removing bonding agents
US2970090A (en) * 1958-07-02 1961-01-31 Melpar Inc Plating nickel on aluminum
US2995479A (en) * 1961-08-08 Degassing aluminum articles
US3077285A (en) * 1961-09-15 1963-02-12 Gen Am Transport Tin-nickel-phosphorus alloy coatings
US3077421A (en) * 1961-03-13 1963-02-12 Gen Am Transport Processes of producing tin-nickelphosphorus coatings
US3244553A (en) * 1959-12-22 1966-04-05 Knapp Mills Inc Process of lead cladding using molten lead
US3459167A (en) * 1968-01-22 1969-08-05 Southwick W Briggs Internal combustion engine
NL6915235A (en) * 1968-10-10 1970-04-14
US4221639A (en) * 1978-10-09 1980-09-09 Kioritz Corporation Aluminium alloy cylinder and manufacturing method thereof
US4974498A (en) * 1987-03-31 1990-12-04 Jerome Lemelson Internal combustion engines and engine components
US5266142A (en) * 1991-11-01 1993-11-30 Decc Technology Partnership A Limited Partnership Coated piston and method and apparatus of coating the same
DE4444491A1 (en) * 1993-12-21 1995-06-22 Miba Gleitlager Ag Method for the production of a sliding bearing
US5435872A (en) * 1991-11-01 1995-07-25 Decc Technology Partnership Sized coated pistons
US5435873A (en) * 1991-11-01 1995-07-25 Decc Technology Partnership, A Limited Partnership Of Which The Decc Company, Inc. Is A General Partner Method and apparatus for sizing a piston
US6495267B1 (en) 2001-10-04 2002-12-17 Briggs & Stratton Corporation Anodized magnesium or magnesium alloy piston and method for manufacturing the same
US6606983B2 (en) 2001-09-18 2003-08-19 Federal-Mogul World Wide, Inc. Ferrous pistons for diesel engines having EGR coating
WO2006010450A1 (en) * 2004-07-26 2006-02-02 Bosch Rexroth Ag Piston rod comprising a covering layer consisting of a cobalt alloy
US20070000468A1 (en) * 2005-05-23 2007-01-04 Miguel Azevedo Coated power cylinder components for diesel engines

Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2995479A (en) * 1961-08-08 Degassing aluminum articles
US2505776A (en) * 1941-07-11 1950-05-02 Shelley Method of manufacture of hollow floats of thin metal for ship compasses
DE969934C (en) * 1943-07-25 1958-07-31 Messerschmitt Boelkow Blohm Composite metal pistons
US2894885A (en) * 1945-01-06 1959-07-14 Allen G Gray Method of applying copper coatings to uranium
US2854737A (en) * 1945-01-06 1958-10-07 Allen G Gray Copper coated uranium article
US2894884A (en) * 1945-01-09 1959-07-14 Allen G Gray Method of applying nickel coatings on uranium
US2854738A (en) * 1945-01-09 1958-10-07 Allen G Gray Nickel coated uranium article
US2509117A (en) * 1946-07-24 1950-05-23 Us Rubber Co Method of making composite wire
US2611163A (en) * 1947-08-20 1952-09-23 Cleveland Graphite Bronze Co Method of making bearings
US2575214A (en) * 1948-09-30 1951-11-13 Wright Aeronautical Corp Piston with plated piston ring grooves
US2933421A (en) * 1949-03-21 1960-04-19 Herbert H Hyman Dissolution method of removing bonding agents
US2682702A (en) * 1949-04-06 1954-07-06 Ohio Commw Eng Co Carbonyl metal plated product
DE897786C (en) * 1951-03-16 1953-11-23 Mahle Kg Pairs of machine parts made of light metal sliding on each other and processes for their production
US2704512A (en) * 1951-12-12 1955-03-22 Metal printing plate and method of
US2761792A (en) * 1952-06-13 1956-09-04 Eutectic Welding Alloys Process for preparing aluminum cables for soldering
US2766195A (en) * 1953-01-26 1956-10-09 American Brake Shoe Co Plated aluminum bearings
US2970090A (en) * 1958-07-02 1961-01-31 Melpar Inc Plating nickel on aluminum
US3244553A (en) * 1959-12-22 1966-04-05 Knapp Mills Inc Process of lead cladding using molten lead
US3077421A (en) * 1961-03-13 1963-02-12 Gen Am Transport Processes of producing tin-nickelphosphorus coatings
US3077285A (en) * 1961-09-15 1963-02-12 Gen Am Transport Tin-nickel-phosphorus alloy coatings
US3459167A (en) * 1968-01-22 1969-08-05 Southwick W Briggs Internal combustion engine
NL6915235A (en) * 1968-10-10 1970-04-14
US4221639A (en) * 1978-10-09 1980-09-09 Kioritz Corporation Aluminium alloy cylinder and manufacturing method thereof
US4974498A (en) * 1987-03-31 1990-12-04 Jerome Lemelson Internal combustion engines and engine components
US5266142A (en) * 1991-11-01 1993-11-30 Decc Technology Partnership A Limited Partnership Coated piston and method and apparatus of coating the same
US5435872A (en) * 1991-11-01 1995-07-25 Decc Technology Partnership Sized coated pistons
US5435873A (en) * 1991-11-01 1995-07-25 Decc Technology Partnership, A Limited Partnership Of Which The Decc Company, Inc. Is A General Partner Method and apparatus for sizing a piston
DE4444491A1 (en) * 1993-12-21 1995-06-22 Miba Gleitlager Ag Method for the production of a sliding bearing
US6606983B2 (en) 2001-09-18 2003-08-19 Federal-Mogul World Wide, Inc. Ferrous pistons for diesel engines having EGR coating
US6495267B1 (en) 2001-10-04 2002-12-17 Briggs & Stratton Corporation Anodized magnesium or magnesium alloy piston and method for manufacturing the same
WO2006010450A1 (en) * 2004-07-26 2006-02-02 Bosch Rexroth Ag Piston rod comprising a covering layer consisting of a cobalt alloy
US20070000468A1 (en) * 2005-05-23 2007-01-04 Miguel Azevedo Coated power cylinder components for diesel engines
US7383807B2 (en) * 2005-05-23 2008-06-10 Federal-Mogul World Wide, Inc. Coated power cylinder components for diesel engines

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