WO1997000980A1 - An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys - Google Patents

An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys Download PDF

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Publication number
WO1997000980A1
WO1997000980A1 PCT/DK1996/000270 DK9600270W WO9700980A1 WO 1997000980 A1 WO1997000980 A1 WO 1997000980A1 DK 9600270 W DK9600270 W DK 9600270W WO 9700980 A1 WO9700980 A1 WO 9700980A1
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WO
WIPO (PCT)
Prior art keywords
nickel
cobalt
bath
current density
msec
Prior art date
Application number
PCT/DK1996/000270
Other languages
French (fr)
Inventor
Peter Torben Tang
Henrik Dylmer
Per MØLLER
Original Assignee
Peter Torben Tang
Henrik Dylmer
Moeller Per
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 Peter Torben Tang, Henrik Dylmer, Moeller Per filed Critical Peter Torben Tang
Priority to AU61884/96A priority Critical patent/AU6188496A/en
Priority to DE69604180T priority patent/DE69604180T2/en
Priority to CA002224382A priority patent/CA2224382C/en
Priority to JP9503524A priority patent/JPH11507991A/en
Priority to EP96920744A priority patent/EP0835335B1/en
Priority to US08/973,556 priority patent/US6036833A/en
Publication of WO1997000980A1 publication Critical patent/WO1997000980A1/en
Priority to NO19975769A priority patent/NO320887B1/en
Priority to GR990402642T priority patent/GR3031549T3/en

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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
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/12—Electroplating: Baths therefor from solutions of nickel or cobalt
    • 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
    • C25D3/562—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of iron or nickel or cobalt
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/18—Electroplating using modulated, pulsed or reversing current
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/60—Electroplating characterised by the structure or texture of the layers
    • C25D5/605—Surface topography of the layers, e.g. rough, dendritic or nodular layers
    • C25D5/611—Smooth layers

Definitions

  • An electroplating method of forming platings of nickel cobalt, nickel alloys or cobalt alloys An electroplating method of forming platings of nickel cobalt, nickel alloys or cobalt alloys.
  • the present invention relates to an electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys in an electrodepositing bath of the type: Watt's bath, chloride bath or a combination thereof by employing pulse plating with a periodic reverse pulse.
  • Current density independence is obtained by means of the invention, whereby low internal stresses are always rendered, wherever the measure ⁇ ment thereof is made on a particular member and whichever current density is used.
  • the most common electrodepositing baths for nickel electroplating are Watt's baths containing nickel sulfate, nickel chloride and usually boric acid; chloride baths containing nickel chloride and boric acid, and sulf amate baths containing nickel sulfamate, nickel chloride and usually boric acid.
  • the latter baths are used for the more complicated platings and are difficult and comparatively expensive in use.
  • Corresponding platings of cobalt may be formed in similar baths containing cobalt sulfate and cobalt chloride instead of the corresponding nickel salts. By adding other metal salts platings of nickel or cobalt alloys are obtained.
  • pulse plating with periodic reverse pulse, i.e. alternating between a cathodic and anodic current.
  • the cathodic current cycle the desired plating formation is obtained by metal deposition, while a portion of the deposited nickel is removed by dissolution in the anodic current cycle, any nodules in the plating thus being smoothed.
  • the anodic load is to be less than the cathodic load. This method is e.g.
  • US patent No. 2,470,775 discloses a process for electroplating nickel, cobalt and alloys thereof in an electrodepositing bath containing chlorides and sulfates of the metals.
  • the plating is effected by means of reversed pulse resulting in an improved appearance (smoothness and maximum brightness) as well as in an expedited deposition.
  • An anodic current density is employed of substantially the same range as the cathodic current density.
  • additives are mentioned in the US patent, including naphthalene -1,5-disulfonic acid. These additives are referred to as advantageous components, however no directions are rendered in connection with these additives or elsewhere in the patent as to how the mechanical internal stresses are reduced in the platings resulting from electroplating.
  • EP patent No. 0.079.642 (Veco Beheer B.V.) relates to pulse plating with nickel in an electrolytic bath of the Watt's bath type comprising butynediol or ethylene cyanohydrin as brightener.
  • the deposition is preferably performed at a pulsating current without anodic cycles, but it is stated that anodic cycles, i.e. reverse pulse, can also be employed with the same result. It is, however, not possible to use long anodic pulses in a pure Watt's bath without passivating the nickel layer, whereby any further deposition is prevented.
  • said patent discloses that the frequen ⁇ cies used are in a range from 100 to 10,000 Hz.
  • DE published specification No. 2.218.967 discloses a bath for electrodeposition of nickel, to which bath a comparatively large amount of sulfonated naphthalene is added, such as from 0.1 mole/1 to saturation so as to reduce the internal stresses in the platings applied by electroplating and with a direct current of e.g. 30 or 60 mA/cm 2 corresponding to 3 to 6 A dm 2 .
  • the internal stresses are only reduced from die undesired tensile stress range to the compressive stress range from 0 to 26,000 psi (approx. 179 MPa) by employing this bath.
  • the present invention relates to an electroplating method of forming platings of nickel, cobalt, nickel or cobalt alloys in an electrodepositing bath belonging to the type of a Watt's bath, a chloride bath or a combination thereof by employing pulse plating with periodic reverse pulse, said method being characterised in tiiat the electrodepositing bath contains an additive selected among sulfonated naphthalenes.
  • Sulfamate baths are more complicated (difficult and more expensive to maintain), but are generally used to reduce the stress in the platings. However, in a sulfamate bath, it is only possible to obtain platings with satisfactorily low internal mechanical stresses in case of simple geometric shapes.
  • Sulfamate baths cannot be used for periodic reverse pulse deposition, sulfur alloyed anodes (2% S) being employed to prevent the sulfamate from decomposing in ammoma and sulfiiric acid (ruining the bath). If the current is reversed, the cathode coated with non-sulfur alloyed nickel or cobalt becomes an anode and the sulfamate is destroyed.
  • sulfur alloyed anodes 2% S
  • the cathode coated with non-sulfur alloyed nickel or cobalt becomes an anode and the sulfamate is destroyed.
  • the invention renders it possible to manufacture complicated geome ⁇ tric shapes completely without or with considerably reduced internal stresses in tiie plating.
  • sulfonated naphthalene is used, i.e. naphthalene sulfonated with from 1 to 8 sulfonic acid groups (- SO 3 H), prefer ⁇ ably with 2 to 5 sulfonic acid groups, most preferred 2-4 sulfonic acid groups.
  • a sulfonated naphthalene product usually comprises a mixture of sulfonated naphthalenes with various degrees of sulfonation, i.e. the number of sulfonic acid groups per naphthalene residue.
  • several isomeric com ⁇ pounds may be present for each degree of sulfonation.
  • the used sulfonated naphthalene sulfonide has a degree of sulfonation on average corresponding to from 2 to 4.5 sulfomc acid groups per molecule, e.g. 2.5- to 3.5 sulfonic acid groups per molecule.
  • a mixture of sulfonated naphthalenes is used as sulfonated naphthalene additive, said mixture according to analysis containing approximately 90% of naphthalene trisulfonic acid, preferably comprisingnaphthalene-l,3,6-trisulfonicacidandnaphthalene-l,3,7-trisulfonicacid.
  • naphthalene residue in the sulfonated naphthalene additive is usually free of other substiments than sulfonic acid groups. Any other substiments may, however, be present provided that they are not detrimental to the beneficial effect of the sulfo ⁇ nated naphthalene additive on minimizing the internal stresses in the plating formed by employing pulse plating.
  • the sulfonated naphthalene additive is used in the electroplating bath in the amount of 0.1 to 10 g/1, more preferred in an amount of 0.2 to 7.0 g/1 and most preferred in an amount of 1.0 to 4.0 g/1, e.g. around 3.1 g/1.
  • the bath composition preferably contains 10- 500 g/1 of NiCl 2 , 0-500 g/1 of NiSO 4 and 10-100 g/1 of H 3 BO 3 , more preferable 100-400 g/1 of NiCl 2 , 0-300 g/1 of NiSO 4 and 30-50 g/1 of H 3 BO 3 and preferable 200-350 g/1 of NiCl 2 , 25- 175 g/1 of NiSO 4 and 35-45 g/1 of H 3 BO 3 , for instance about 300 g/1 of NiCl 2 , 50 g/1 of NiSO 4 and 40 g/1 of H 3 BO 3 .
  • the anodic current density I A is at least 1.5 times the cathodic current density I , more preferable when I A ranges from 1.5 to 5.0 times the I ⁇ and most preferable when I A is 2 to 3 times the I ⁇ .
  • the method according to the invention may be character ⁇ ised in that the pulsating current is made up of cathodic cycles, each of a duration T ⁇ of from 2.5 to 2000 msec, and at a cathodic current density I ⁇ of 0.1 to 16 A/dm 2 alternating with anodic cycles, each of a duration of from 0.5 to 80 msec, and at an anodic current density I A of 0.15 to 80 A/dm 2 .
  • a more preferable embodi ⁇ ment according to the invention is obtained when among the pulse parameters the I ⁇ ranges from 2 to 8 A/dm 2 , the T ⁇ ranges from 30 to 200 msec, the I A ranges from 4 to 24 A/dm 2 and T A ranges from 10 to 40 msec.
  • a particular preferred embodiment is obtained when I ⁇ is from 3 to 6 A/dm 2 , T ⁇ is from 50 to 150 msec. , I A is from 7 to 17 A/dm 2 and T A is from 15 to 30 msec, e.g. when I ⁇ is 4 A/dm 2 , T ⁇ is 100 msec, I A is 10 A/dm 2 and T A is 20 msec.
  • a nickel bath containing 300 g/1 of NiCl 2 -6H 2 O and 50 g/1 of NiSO 4 *6H 2 O was admixed, and to which bath 40 g/1 of H 3 BO 3 and 3.1 g/1 of sulfonated naphthalene additive of technical grade comprising 90% naphthalene- 1, 3, 6/7-trisulf onic acid were added.
  • Nickel was deposited on a steel strip fixed in a dilatometer so that the internal stresses in the deposited nickel can be measured as a contraction or a dilation of the steel strip.
  • the temperamre of the bath was 50°C.
  • the internal stresses were measured to be 0 MPa or less than the degree of accuracy of the apparams of approximately ⁇ 10 MPa.
  • Example 2 Following the method according to Example 1 with the exception that only 1.1 g/1 of the same sulfonated naphthalene additive was used, the same result was obtained as in Example 1, i.e. that the internal stresses were to measure to 0 MPa or less than the degree of accuracy of the apparatus of approximately ⁇ 10 MPa.
  • Example 2 Following the method according to Example 2 with the exception that the anodic current density I A and the cathodic current density I ⁇ was set at 1.25 A/dm 2 and 0.5 A/dm 2 respectively, the same result as in Example 1 was obtained, i.e. that the intemal stresses were measured to 0 MPa or less than the degree of accuracy of the apparams of approximately ⁇ 10 MPa.
  • Example 3 Following the method according to Example 3 with the exception that the anodic current density I A and the cathodic current density I ⁇ was set at 18.75 A/dm 2 and 7.5 A/dm 2 respectively, the same result as in Example 1 was obtained, i.e. that the internal stresses were measured to 0 MPa or less than the degree of accuracy of the apparams of approximately ⁇ 10 MPa.
  • Example 6 Following the method according to Example 5 with the exception that 1.1 g/1 of sulfonated naphthalene additive was used, similar stress-free cobalt platings may be expected.
  • Example 2 Employing the same set-up and materials as in Example 1 , but at a direct current of 4 A/dm 2 , the intemal stresses for comparison with said Example were measured to 377 MPa.
  • Example 2 Employing the same set-up and materials as in Example 2, but using a direct current of 7.5 A/dm 2 , the intemal stresses were measured to 490 MPa.

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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)
  • Electroplating Methods And Accessories (AREA)
  • Electrolytic Production Of Metals (AREA)

Abstract

An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys with reduced stresses in an electrodepositing bath of the type: Watt's bath, chloride bath or a combination thereof, by employing pulse plating with periodic reverse pulse and a sulfonated naphthalene additive. This method makes it possible to deposit nickel, cobalt, nickel or cobalt platings without internal stresses.

Description

An electroplating method of forming platings of nickel cobalt, nickel alloys or cobalt alloys.
Technical Field
The present invention relates to an electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys in an electrodepositing bath of the type: Watt's bath, chloride bath or a combination thereof by employing pulse plating with a periodic reverse pulse. Current density independence is obtained by means of the invention, whereby low internal stresses are always rendered, wherever the measure¬ ment thereof is made on a particular member and whichever current density is used.
Background Art
The most common electrodepositing baths for nickel electroplating are Watt's baths containing nickel sulfate, nickel chloride and usually boric acid; chloride baths containing nickel chloride and boric acid, and sulf amate baths containing nickel sulfamate, nickel chloride and usually boric acid. The latter baths are used for the more complicated platings and are difficult and comparatively expensive in use.
Corresponding platings of cobalt may be formed in similar baths containing cobalt sulfate and cobalt chloride instead of the corresponding nickel salts. By adding other metal salts platings of nickel or cobalt alloys are obtained.
It is known to employ a pulsating current, confer for instance W. Kleinekathofer et al, Metalloberfl. 9 (1982), page 411-420, where pulse plating is used by alternating between equal periods of a direct current with a current density of 1 to 20 A/dm2 and non-current periods, the pulse frequency being from 100 to 500 Hz. By employ¬ ing a pulsating current and as result of the individual current impulses, an increased formation of crystal nucleuses is obtained, thus rendering a more fine-grained and hard plating.
It is furthermore known to employ pulse plating with periodic reverse pulse, i.e. alternating between a cathodic and anodic current. In the cathodic current cycle, the desired plating formation is obtained by metal deposition, while a portion of the deposited nickel is removed by dissolution in the anodic current cycle, any nodules in the plating thus being smoothed. In order to ensure that the result is a build-up and not a dissolution of the plating, it is appreciated that the anodic load is to be less than the cathodic load. This method is e.g. described by Sun et al., Metal Fimshing, May, 1979, page 33-38, whereby the highest degree of hardness in the plating is obtained at a ratio between the cathodic and the anodic current density of 1:1 with cathodic cycles Tκ of 60 msec, alternating with anodic cycles TA of 20 msec.
US patent No. 2,470,775 (Jernstedt et al.) discloses a process for electroplating nickel, cobalt and alloys thereof in an electrodepositing bath containing chlorides and sulfates of the metals. The plating is effected by means of reversed pulse resulting in an improved appearance (smoothness and maximum brightness) as well as in an expedited deposition. An anodic current density is employed of substantially the same range as the cathodic current density. Various additives are mentioned in the US patent, including naphthalene -1,5-disulfonic acid. These additives are referred to as advantageous components, however no directions are rendered in connection with these additives or elsewhere in the patent as to how the mechanical internal stresses are reduced in the platings resulting from electroplating.
EP patent No. 0.079.642 (Veco Beheer B.V.) relates to pulse plating with nickel in an electrolytic bath of the Watt's bath type comprising butynediol or ethylene cyanohydrin as brightener. The deposition is preferably performed at a pulsating current without anodic cycles, but it is stated that anodic cycles, i.e. reverse pulse, can also be employed with the same result. It is, however, not possible to use long anodic pulses in a pure Watt's bath without passivating the nickel layer, whereby any further deposition is prevented. Moreover, said patent discloses that the frequen¬ cies used are in a range from 100 to 10,000 Hz.
None of the above mentioned publications relate to internal stresses in platings. US patent No. 3,437,568 relates to a method for measuring the internal stresses in electroformed parts, but does not advise how to reduce the internal stresses and does not relate to pulse plating, additives or special nickel baths.
DE published specification No. 2.218.967 discloses a bath for electrodeposition of nickel, to which bath a comparatively large amount of sulfonated naphthalene is added, such as from 0.1 mole/1 to saturation so as to reduce the internal stresses in the platings applied by electroplating and with a direct current of e.g. 30 or 60 mA/cm2 corresponding to 3 to 6 A dm2. According to the publication, the internal stresses are only reduced from die undesired tensile stress range to the compressive stress range from 0 to 26,000 psi (approx. 179 MPa) by employing this bath.
Usually, the use of said additive only results in a reduction in the stresses in the range from approx. 300 MPa tensile stress to 100 MPa compressive stress and die stress curve is merely moved downward, but is still a function of the current density, which is a normal condition for any type of nickel bath with or without additives.
The use of the large amount of additive is, however, also encumbered widi several drawbacks, since the additive is expensive, has detrimental effects on the environ¬ ment and may cause damage to the bath.
Thus, an electroplating method, wherein die internal stresses are independent of the current density, cannot be deduced from die teachings of DE 2.218.967. When electroplating members of a simple geometric shape, often comparatively modest variations in the current density occur over different areas of the surface of the members. However, this is not possible when dealing with more complicated geometric shapes, wherein the method according to DE 2.218.967 cannot be employed in practise.
Internal mechanical stress is a problem in all nickel and cobalt depositions, even though the process can be controlled satisfactorily in some instances (by means of expensive electrolytes (sulfamate bath), temperature control, concentration, etc.) when dealing with simple geometric shapes. The prior art methods are, however, completely inapplicable for the manufacture of tools for injection moulding, micro mechanical components or similar complicated geometric shapes.
Consequently, it is desirable to provide a metiiod, whereby nickel, cobalt, nickel or cobalt alloys can be deposited with substantially reduced or completely widiout internal stresses - even in complicated geometric shapes. It is also desirable diat this result is obtained whichever current density is used for the deposition.
Disclosure of the invention
The present invention relates to an electroplating method of forming platings of nickel, cobalt, nickel or cobalt alloys in an electrodepositing bath belonging to the type of a Watt's bath, a chloride bath or a combination thereof by employing pulse plating with periodic reverse pulse, said method being characterised in tiiat the electrodepositing bath contains an additive selected among sulfonated naphthalenes.
By employing the method according to the invention internal stresses which constitu¬ tes a serious problem can be avoided when forming said platings on geometric shapes of a more complicated structure.
Best Mode for Carrying Out the Invention
Sulfamate baths are more complicated (difficult and more expensive to maintain), but are generally used to reduce the stress in the platings. However, in a sulfamate bath, it is only possible to obtain platings with satisfactorily low internal mechanical stresses in case of simple geometric shapes.
Although sulfamate baths are also used in more complicated geometric shapes, as these present the hitherto best known solution, often the result is not the optimum due to heavy internal stresses in the plating which e.g. may cause deformation or cracks.
Sulfamate baths cannot be used for periodic reverse pulse deposition, sulfur alloyed anodes (2% S) being employed to prevent the sulfamate from decomposing in ammoma and sulfiiric acid (ruining the bath). If the current is reversed, the cathode coated with non-sulfur alloyed nickel or cobalt becomes an anode and the sulfamate is destroyed.
When using a Watt's bath, a chloride bath or a combination thereof, it is not possible to obtain platings using a direct current without tensile stresses. In sulfama¬ te baths the stress in the plating - from compressive stress through stress-free to tensile stresses - depends on the cathodic current intensity Iκ. Consequently, on simple geometric shapes stress-free platings can be obtained by means of a sulfamate bath at a specific Iκ which depends on the temperature and may e.g. be of approxi¬ mately 10 A/dm2, but on more complicated geometric shapes this current intensity Iκ is not distributed evenly on the entire surface of the member and causes internal stresses.
The use of the combination according to the invention has surprisingly shown that the internal stresses are very small and independent ofthe cathodic current intensity Iκ and thus of the current distribution on the surface. As a result, low internal stresses are obtained wherever on the member the internal stress is measured and independent of the actual local current densities.
In this manner, the invention renders it possible to manufacture complicated geome¬ tric shapes completely without or with considerably reduced internal stresses in tiie plating.
As additive in the method according to the invention, sulfonated naphthalene is used, i.e. naphthalene sulfonated with from 1 to 8 sulfonic acid groups (- SO3H), prefer¬ ably with 2 to 5 sulfonic acid groups, most preferred 2-4 sulfonic acid groups. In practice, a sulfonated naphthalene product usually comprises a mixture of sulfonated naphthalenes with various degrees of sulfonation, i.e. the number of sulfonic acid groups per naphthalene residue. Moreover, several isomeric com¬ pounds may be present for each degree of sulfonation.
Typically, the used sulfonated naphthalene sulfonide has a degree of sulfonation on average corresponding to from 2 to 4.5 sulfomc acid groups per molecule, e.g. 2.5- to 3.5 sulfonic acid groups per molecule.
In the presently preferred embodiment of the invention, a mixture of sulfonated naphthalenes is used as sulfonated naphthalene additive, said mixture according to analysis containing approximately 90% of naphthalene trisulfonic acid, preferably comprisingnaphthalene-l,3,6-trisulfonicacidandnaphthalene-l,3,7-trisulfonicacid.
The naphthalene residue in the sulfonated naphthalene additive is usually free of other substiments than sulfonic acid groups. Any other substiments may, however, be present provided that they are not detrimental to the beneficial effect of the sulfo¬ nated naphthalene additive on minimizing the internal stresses in the plating formed by employing pulse plating.
In a particular preferred embodiment according to the invention, the sulfonated naphthalene additive is used in the electroplating bath in the amount of 0.1 to 10 g/1, more preferred in an amount of 0.2 to 7.0 g/1 and most preferred in an amount of 1.0 to 4.0 g/1, e.g. around 3.1 g/1.
Moreover, according to the invention the bath composition preferably contains 10- 500 g/1 of NiCl2, 0-500 g/1 of NiSO4 and 10-100 g/1 of H3BO3, more preferable 100-400 g/1 of NiCl2, 0-300 g/1 of NiSO4 and 30-50 g/1 of H3BO3 and preferable 200-350 g/1 of NiCl2, 25- 175 g/1 of NiSO4 and 35-45 g/1 of H3BO3, for instance about 300 g/1 of NiCl2, 50 g/1 of NiSO4 and 40 g/1 of H3BO3.
It has proved advantageous that the anodic current density IA is at least 1.5 times the cathodic current density I , more preferable when IA ranges from 1.5 to 5.0 times the Iκ and most preferable when IA is 2 to 3 times the Iκ.
In a preferred embodiment, the method according to the invention may be character¬ ised in that the pulsating current is made up of cathodic cycles, each of a duration Tκ of from 2.5 to 2000 msec, and at a cathodic current density Iκ of 0.1 to 16 A/dm2 alternating with anodic cycles, each of a duration of from 0.5 to 80 msec, and at an anodic current density IA of 0.15 to 80 A/dm2. A more preferable embodi¬ ment according to the invention is obtained when among the pulse parameters the Iκ ranges from 2 to 8 A/dm2, the Tκ ranges from 30 to 200 msec, the IA ranges from 4 to 24 A/dm2 and TA ranges from 10 to 40 msec. A particular preferred embodiment is obtained when Iκ is from 3 to 6 A/dm2, Tκ is from 50 to 150 msec. , IA is from 7 to 17 A/dm2 and TA is from 15 to 30 msec, e.g. when Iκ is 4 A/dm2, Tκ is 100 msec, IA is 10 A/dm2 and TA is 20 msec.
Examples
Example 1
A nickel bath containing 300 g/1 of NiCl2-6H2O and 50 g/1 of NiSO4*6H2O was admixed, and to which bath 40 g/1 of H3BO3 and 3.1 g/1 of sulfonated naphthalene additive of technical grade comprising 90% naphthalene- 1, 3, 6/7-trisulf onic acid were added.
Nickel was deposited on a steel strip fixed in a dilatometer so that the internal stresses in the deposited nickel can be measured as a contraction or a dilation of the steel strip. The temperamre of the bath was 50°C. When nickel was deposited from said bath at a pulsating current having the cathodic pulse of 100 msec, and 3.5 A/dm2 followed by an anodic pulse of 20 msec and 8.75 A/dm2, the internal stresses were measured to be 0 MPa or less than the degree of accuracy of the apparams of approximately ± 10 MPa.
Example 2 Following the method according to Example 1 with the exception that only 1.1 g/1 of the same sulfonated naphthalene additive was used, the same result was obtained as in Example 1, i.e. that the internal stresses were to measure to 0 MPa or less than the degree of accuracy of the apparatus of approximately ± 10 MPa.
Example 3
Following the method according to Example 2 with the exception that the anodic current density IA and the cathodic current density Iκ was set at 1.25 A/dm2 and 0.5 A/dm2 respectively, the same result as in Example 1 was obtained, i.e. that the intemal stresses were measured to 0 MPa or less than the degree of accuracy of the apparams of approximately ± 10 MPa.
Example 4
Following the method according to Example 3 with the exception that the anodic current density IA and the cathodic current density Iκ was set at 18.75 A/dm2 and 7.5 A/dm2 respectively, the same result as in Example 1 was obtained, i.e. that the internal stresses were measured to 0 MPa or less than the degree of accuracy of the apparams of approximately ± 10 MPa.
Example 5
Using the method according to Example 1, in which the nickel bath containing 300 g/1 of NiCl2-6H2O and 50 g/1 of NiSO4-6H2O is substimted by 300 g/1 of CoCl2. *6H2O and 50 g/1 of CoSO4'6H O and the same amount of H3BO3 and sulfonated naphthalene additive, similar cobalt platings can be produced which are expected to have the similar low internal stresses.
Example 6 Following the method according to Example 5 with the exception that 1.1 g/1 of sulfonated naphthalene additive was used, similar stress-free cobalt platings may be expected.
Example 7
Following the method according to Example 6 with the exception that the anodic current density IA and the cathodic current density Iκ was set at 1.25 A/dm2 and 0.5 A/dm2 respectively, similar stress-free cobalt platings can be expected.
Example 8
Following the method according to Example 7 with the exception that the anodic current density IA and the cathodic current density Iκ was set at 18.75 A/dm2 and 7.5 A/dm2 respectively, similar stress-free cobalt platings are expected.
Comparison Examples
Comparison Example 1
Employing the same set-up and materials as in Example 1 , but at a direct current of 4 A/dm2, the intemal stresses for comparison with said Example were measured to 377 MPa.
Comparison Example 2
Employing the same set-up and materials as in Example 2, but using a direct current of 7.5 A/dm2, the intemal stresses were measured to 490 MPa.
Comparison Example 3
Employing the same set-up and materials as in Example 2, but instead using a pulsating current without reverse pulse (Iκ = 3.5 A/dm2, Tκ = 100 msec, IA = 0 A dm2, TA= 20 msec), the intemal stresses were measured to 410 MPa.

Claims

Claims
1. An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys in an electrodepositing bath belonging to the type of Watt's bath, chloride bath or a combination thereof by employing pulse plating with periodic reverse pulse, characterised in that the electrodepositing bath contains sulfonated naphthalene as an additive and that an anodic current density IA at least 1.5 times the cathodic current density Iκ is used at the pulse plating.
2. Method according to claim 1, characterised in the use of a sulfonated naphthalene additive in form of sulfonated naphthalene having an average degree of sulfonation of 1 to 6 sulfonic acid groups per naphthalene residue.
3. Method according to claim 2, characterised in that the sulfonated naphthalene additive has an average degree of sulfonation of 2 to 5 sulfonic acid groups per naphthalene residue.
4. Method according to claim 1 for the formation of nickel platings, c h a r a c t- e r i s e d in that the bath composition comprises 10 to 500 g/1 of NiCl2, 0 to 500 g/1 of NiSO4 and 10 to 100 g/1 of H3BO3, preferably 100 to 400 g/1 of NiCl2, 0 to 300 g/1 of NiSO4 and 30-50 g/1 of H3BO3, particularly preferable 200 to 350 g/1 of NiCl2, 25 to 175 g/1 of NiSO4 and 35 to 45 g/1 of H3BO3.
5. Method according to claim 1, characterised in that the anodic current density IA is from 1.5 to 5.0 times the Iκ, preferably 2 to 3 times the Iκ.
6. Method according to claim 1, characterised in that the pulsating current is made up of cathodic cycles, each of a duration Tκ of from 2.5 to 2000 msec at a pulsating or uniform cathodic current density Iκ of 0.1-16 A/dm2 alterna¬ ting with anodic cycles, each of a duration TA of from 0.5 to 80 msec, at an anodic current density IA of 0.15-80 A/dm2.
7. Method according to claim 6, characterised in that the pulsating current is made up of cathodic cycles, each of a duration Tκ of from 30 to 200 msec, at a cathodic current density Iκ of 2-8 A/dm2 alternating with anodic cycles, each of a duration TA of from 10 to 40 msec, at an anodic current density IA of 5 to 20 A/dm2.
8. Pulsating current according to claim 7, characterised in that the pulse parameters Iκ, Tκ, IA, TA is 4 A/dm2, 100 msec, 10 A/dm2 and 20 msec, respectively.
9. Method according to claim 1, characterised in that the additive is used in the amount of 0.1 to 10 g/1, preferably 0.2 to 7.0 g/1 and particularly 1 to 4 g/1.
PCT/DK1996/000270 1995-06-21 1996-06-20 An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys WO1997000980A1 (en)

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AU61884/96A AU6188496A (en) 1995-06-21 1996-06-20 An electroplating method of forming platings of nickel, cobat, nickel alloys or cobalt alloys
DE69604180T DE69604180T2 (en) 1995-06-21 1996-06-20 ELECTROPLATING METHOD FOR PRODUCING COATINGS FROM NICKEL, COBALT, NICKEL OR COBALT ALLOYS
CA002224382A CA2224382C (en) 1995-06-21 1996-06-20 An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys
JP9503524A JPH11507991A (en) 1995-06-21 1996-06-20 Electroplating method for forming nickel, cobalt, nickel alloy or cobalt alloy plating
EP96920744A EP0835335B1 (en) 1995-06-21 1996-06-20 An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys
US08/973,556 US6036833A (en) 1995-06-21 1996-06-20 Electroplating method of forming platings of nickel
NO19975769A NO320887B1 (en) 1995-06-21 1997-12-08 Electrolytic coating method for forming nickel, cobalt, nickel or cobalt alloy plating
GR990402642T GR3031549T3 (en) 1995-06-21 1999-10-15 An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys

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DK199500706A DK172937B1 (en) 1995-06-21 1995-06-21 Galvanic process for forming coatings of nickel, cobalt, nickel alloys or cobalt alloys
DK0706/95 1995-06-21

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EP1044776A1 (en) * 1999-03-17 2000-10-18 Sony DADC Austria AG Nickel plating of a mould using pulsating current
US6641710B2 (en) 2000-08-29 2003-11-04 Soqi, Inc. Metal plating method
DE10259362A1 (en) * 2002-12-18 2004-07-08 Siemens Ag Process for depositing an alloy on a substrate
US6892002B2 (en) 2001-03-29 2005-05-10 Ibsen Photonics A/S Stacked planar integrated optics and tool for fabricating same
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2470775A (en) * 1947-07-09 1949-05-24 Westinghouse Electric Corp Electroplating nickel and cobalt with periodic reverse current
DE2020840A1 (en) * 1969-05-07 1971-02-04 London Scandinavian Metall Bath for the galvanic deposition of nickel and nickel alloys
DE2218967A1 (en) * 1971-04-23 1972-11-09 United States Atomic Energy Commission, Washington, D.C. Nickel plating substances and uses
WO1994012695A1 (en) * 1992-11-30 1994-06-09 Queen's University At Kingston Nanocrystalline metals

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3437568A (en) * 1966-07-18 1969-04-08 Electro Optical Systems Inc Apparatus and method for determining and controlling stress in an electroformed part
US3741234A (en) * 1971-04-26 1973-06-26 Liquid Controls Corp Valve
NL8105150A (en) * 1981-11-13 1983-06-01 Veco Beheer Bv METHOD FOR MANUFACTURING SCREEN MATERIAL, SCREENING MATERIAL OBTAINED, AND APPARATUS FOR CARRYING OUT THE METHOD

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2470775A (en) * 1947-07-09 1949-05-24 Westinghouse Electric Corp Electroplating nickel and cobalt with periodic reverse current
DE2020840A1 (en) * 1969-05-07 1971-02-04 London Scandinavian Metall Bath for the galvanic deposition of nickel and nickel alloys
DE2218967A1 (en) * 1971-04-23 1972-11-09 United States Atomic Energy Commission, Washington, D.C. Nickel plating substances and uses
WO1994012695A1 (en) * 1992-11-30 1994-06-09 Queen's University At Kingston Nanocrystalline metals

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DE69604180T2 (en) 2000-03-09
US6036833A (en) 2000-03-14
EP0835335B1 (en) 1999-09-08
DE69604180D1 (en) 1999-10-14
DK172937B1 (en) 1999-10-11
ATE184332T1 (en) 1999-09-15
NO320887B1 (en) 2006-02-06
GR3031549T3 (en) 2000-01-31
CA2224382C (en) 2005-07-19
CA2224382A1 (en) 1997-01-09
NO975769D0 (en) 1997-12-08
ES2136421T3 (en) 1999-11-16
EP0835335A1 (en) 1998-04-15
AU6188496A (en) 1997-01-22
DK70695A (en) 1996-12-22
JPH11507991A (en) 1999-07-13
NO975769L (en) 1997-12-08

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