Classifications

• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/56—Electroplating: Baths therefor from solutions of alloys
  • C25D3/565—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of zinc

Definitions

• Still another object of this invention is to provide a novel electro-plating process to obtain anti-corrosive properties and to be endurable for mechanical proceedings after the plating.
• the plated coating layers according to this process consist of highly uniform fine-grained structures in view of their crystallization and free from the pinholes.
• the zinc-titanium-zirconium alloy coatings are well-deposited and superior in anti-tension, and have workability for deep-pressing after the plating, and have a remarkable higher hardness the Vickers value is 110 up as compared with the value of conventional zinc coating the Vickers hardness is -40, and have the superior brightness. Further, the galvanized layers have superior anti-corrosive properties.
• One of the remarkable advantages of this invention may be carried into effect with use of such a high current density as is 8120 amperes per square decimeter as compared with a conventional alkaline zinc plating which is 2-3 amperes per square decimeter.
• the plating according to this process may be carried with advantageous efficiency as rapid as several times than in the case of conventional zinc plating, without any porous deposition.
• the process may be carried into eifect with use of a current density of 6-8 amperes per square decimeter, with equal results.
• metallic zinc is employed as anode, so that titanium and zirconium compounds contained in the plating bath will be consumed as the plating proceeds.
• the electrolysis therefore, must be carried into effect with periodical replenishment of the titanium compound and the zirconium compound.
• a continuously operating filter is connected to the plating tank and the filter is charged with the titanium compound and the zirconium compound.
• the plating bath is continuously circulated 3,070,521 Patented Dec. 25, 1962 through the filter, thereby dissolving the titanium and the zirconium compounds in the solution to the saturated concentration.
• Example I To a zinc cyanide plating bath, containing 60 grams of zinc cyanide, 45 grams of sodium cyanide and grams of caustic soda per liter of solution, are continuously added sodium pertitanate and sodium perzirconate so as to maintain the concentration at a rate each of 0.5-1 gram per litre of solution, in such a way that the liquid is continuously passed through a filter charged with the titanium and the zirconium compounds.
• the plating is carried into effect, using a metallic zinc plate as anode with a cathodic current density of 10 amperes per square decimeter for a duration of 4 minutes, thus obtaining a uniform, bright, superior and well-deposited layer of zinctitanium-zirconium alloy.
• the thus coated layer is 15 microns in its thickness and contains about 0.3% of titanium and about 0.3% of zirconium, as determined by the spectrum analysis, and perfectly certified by the Mattauchs mass analysis that titanium and zirconium in the deposited layer remain in metallic state.
• Example 2 In the case of the barrel plating, the process may be carried into effect with use of a current density of 6 amperes per square decimeter for a duration of 10 minutes, thus obtaining a coated layer of 13,u in its thickness, with equal results.
• the thus obtained coating shows a higher anticorrosive quality as strong as several times than in the case of conventional zinc platings, as determined upon a number of tests using salt spray and dew point by the exposure tests.
• zinc-titanium-zirconium alloy plating may be produced in an incredibly efiective manner and with substantially superior anti-corrosive qualities, and in much shorter time than those obtainable in the case of conventional zinc plating.
• the plating also is obtainable in a uniform layer on complicated forms to have superior uniform galvanizing properties and endurable for mechanical proceedings after the plating.
• the process according to this invention therefore, represents thus a highly advantageous plating method, which is easily carried into practice industrially and on the anti-corrosive techniques of iron and steel.
• a process for electroplating an alloy of zinc-titanium-zirconium on a cathode comprising employing a zinc anode, an aqueous electrolytic bath in the following quantities per liter of water:
• a process for electroplating an alloy of zinc-titanium-zirconium on a cathode comprising employing a zinc anode, an aqueous electrolytic bath in the following quantities per liter of water:
• a process for electroplating an alloy of zinc-titanium-zirconium on a cathode comprising employing a zinc anode, an aqueous electrolytic bath in the following quantities per liter of water:
• grams of zinc cyanide 45 grams of sodium cyanide About 0.5-1 gram of sodium pertitanate about 0.5-1 gram of sodium perzirconate grams of sodium hydroxide undertaking the electroplating with a current density of between 6-10 amperes per decimeter for between 10-4 minutes.

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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)
• Electroplating And Plating Baths Therefor (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=12446294

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (1)

• 1961
  • 1961-03-06 US US93357A patent/US3070521A/en not_active Expired - Lifetime
  • 1961-08-12 DE DET20594A patent/DE1232801B/de active Pending
  • 1961-08-18 GB GB29943/61A patent/GB919814A/en not_active Expired
  • 1961-08-21 CH CH975461A patent/CH398246A/de unknown

Patent Citations (1)

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