DE2026406A1 - Corrosion-resistant multilayer metal coating - Google Patents

Description

Nihon Kagaku ^ Kabushiki Kaisha Tokyo (Japan)

Corrosion-resistant multilayer metal coating

The invention relates to a corrosion-resistant multilayer metal coating, in particular one multilayer metal coating, in which one under the The outer layer consists of nickel, cobalt or a nickel or cobalt alloy and phosphorus contains, and a method for producing such a coating on a metallic or non-metallic Base material.

Ej of the increasing use of durable consumer goods and the progress in the automotive industry are processes for producing, eineo ITiokelüberzugea approaches have been wound, the int particularly suitable and is characterized for a particular purpose by good appearance and good Korroaioneechutzwirkung tin · ·

009849/1721

2026408

At present, methods are mainly used for producing corrosion-resistant metal coatings by nickel plating in which a copper coating is formed on a base material, a copper coating is used on the base material nickel plating consisting of one or more layers is formed, and on the nickel plating

thin outer coating of chrome is formed. It is the copper plating is not absolutely necessary.

These common methods result in a coating that looks good, but is not sufficiently resistant to corrosion.

In the method according to the invention, a phosphorus-containing layer made of nickel, cobalt or a nickel or. Cobalt alloy is made, and common metal layers are also made, one of which is on the phoaphor-containing layer is arranged as the outer layer. This process results in a multilayer metal coating, which is very corrosion-resistant or can be very thin without affecting the good appearance and the corrosion resistance can be impaired.

A corrosive multi-layer metal coating on a metallic or non-metallic base material. According to the requirements, it is characterized in that the coating under the outer layer is a basic layer made of phoäphorha! .Ti _t ; om lliakel, phosphorus-containing cobalt, othu " phojph n-containing liickel-cobalt-Ijeü'ieruiu? be-Ht-ilit and in: inon. -alvaaiaohen odor currentless ve L ¹ fnhi "ea hj) \; 3is Lj lit been iat.

09849/1721

BAD OBSGtNAL I

A method for producing the multilayered metal coating on a base material based on iron is characterized according to the invention in that with a decrease in the amount deposited per unit of time, the bath f. distributed iron is added in order to increase the amount of deposited iron per unit of time again.

A phosphorus ige Ilickelschicht one can after one of the procedure given below:

(1) Electroless nickel plating by reducing nickel ions with hypophosphite ions;

(2) Electroplated nickel plating using a nickel electroplating bath, to which phosphates and phosphites have been added;

(3) Electroplated nickel plating with one placed in the bath Nickel-phosphorus alloy cathode.

A phosphorus-containing cobalt slice can be obtained according to the following given procedure received »

(4) electroplating cobalt with an electroplating bath, which contains cobalt sulfate, phosphates and phosphites.

A phosphite-containing nickel-cobalt alloy can be obtained from received one of the procedures given below »

¹ :) Electroless plating and
' ".' ■ Electroplating.

009849/1721

The inventors first considered the relationship between the Phosphorus content of a phosphorus-containing nickel coating and investigated its corrosion resistance.

There are several methods of testing corrosion resistance a metal coating. The corrosion resistance of multilayered metal coatings was after ASTM B 38O-6IT tested. The coatings became several Subjected to Test Cycles »In each test cycle, the coating Maintained motionless for twenty hours in a container filled with warm, humid air

The specimens consisted of polished steel sheet pieces of 50 100 χ 0.3 mm according to the Japanese standard JIS 0-3141 as substrates carrying the coating and had an angular, narrow groove formed by scraping »

The test specimens, degreased in the usual way and freed from rust, were divided into three groups, which were then provided with coatings in the corresponding baths. The operating conditions were chosen so that kickel coatings with a phosphorus content of $ 1, $ 5 or 10 ^c ß> were obtained. These conditions are shown in Table 1.

009849/1721

Table 1

Composition of the bath and operating conditions for Formation of a P-containing Ni coating

Bad for Ni Bad for Ni Bad for Ni

Cover with Cover with Cover with

1 # P 5 $ P 10 $ P

150 150 250

100 150 150

40 20 70

100 85 85

1 1 1

Bath temperature, ⁰ C 70 70 70

Anode current density, A / dm 6 5 6

Speed of

Hickel coating formation, 1.0 0.8 0.2

Micrometer / minο

During the formation of the coating, the composition of the bath for producing a Ni coating with 1 ^a fi> P can change somewhat without the composition of the coating deviating from the desired composition. In particular, there is a tendency for the phosphorus content to increase. Furthermore, during the formation of the coating, the composition of the bath for forming a Ni coating of 10 $ P may change somewhat without the composition of the coating being changed

Components of Baths and Characteristic values ITiSO »· οΗ_0 ·
Δ. c. g / l HiOl ₂ OOH ₂ O, g / l H ₃ PO ₃ , g / l H ₃ PO ₄ , sA pH, with
set NaOH

009849/1721

the desired composition is different in particular a tendency towards a decrease in the phosphorus content ο the bath to produce a coating with 5? ί Ρ Of the three baths used, it had the most stable composition.

The coated specimens in each of the three groups had phosphorus-containing coatings with thicknesses of 2, 5, 15 and 35, respectively Micrometers · Some of the specimens were additionally provided with a 0.25 micrometer thick chrome coating.

The test specimens provided with the two-layer coating were subjected to a test cycle to test for corrosion resistance subject to ASTM B 38O-61T ,, The results of this test are given in Table 2, in which the corrosion resistance of each of the coated specimens indicated by a rating number (ASTM) is «The relationship between the rating number and the corrosion given below:

Rating number Corrosion, ° / o 0.1 10 O 0.25 9 0.0 - 0.5 8th 0.1 - 1.0 7th 0.25 - 2.5 6th 0.5 - 5.0 5 1.0 - 10.0 4th 2.5 - 25.0 3 5.0 - 50.0 2 10.0 - 100 $> O; ₁ 25.0 - 0 50.0 -

009849/1721

20264

For the formation of a phosphorus-containing hickel layer one can a bath having the following composition below Use conditions:

100 - 300 g / l 50 - 200 g / l 20-100 g / l 50 - 100 g / l

2 or less 60 - 80 ° C

3 - 10 A / dm ²

^H 3 ^PO 3

PH value
Bath temperature cathode current density

Table 2

Relationship between the phosphorus content and the thickness of the nickel coating and the corrosion resistance of the coated Test items

• f

Corrosion resistance of the coated specimens

P-content of the P-containing hickel coating

Thickness of the P-containing nickel coating, Micrometer 2 5 15

6th 9 10 9 7 "■ 9 10 10 7th 9 10 10

009849/1721

For a comparison of those given in Table 2 phosphorus-containing nickel coatings and the usual multilayer nickel coatings with regard to their corrosion resistance The following test specimens were subjected to the test in accordance with ASTM B 38O-611:

a) A specimen with a 1.5 micrometer thick, semi-bright nickel layer, a 5 micrometer thick, bare ITiekelschicht and a 0.25 micrometer thick Sargent chrome layer, in the order shown ^

/ covered warj

b) A test specimen from the same substrate that was used with a 15 micrometers thick, semi-bright nickel layer, a 5 micrometers thick, bright nickel layer, a 2 micron thick hard nickel layer and one 0.25 micrometer thick Sargent chrome layer * iii der

. specified by-order, was covered *

When tested for corrosion resistance, the Examinee a) the evaluation number 6 and the examinee b) the Rating number 9

The following is based on the above test results stands out.

1 · The phosphorus-containing niocel coatings have a higher Corrosion resistance than the most corrosion resistant nickel coatings known ·.

2. The change in the phosphorus content of the Niolctlschioht the multi-layered metal coating has only tinen aehr little or no influence on the corrosion resistance of the multilayer metal coating.

009849/1721

Phosphoruslialtige3 nickel, however, has a great hardness and a low flexural strength, so that in the practical use of a coating consisting of it the following Difficulties arise:

In ilgurs 1 to 5 there is a gradual decrease in the Uniformity of a phosphorus-containing nickel coating with an increasing content of iron (III) ions in one strong acidic bath from which the coating is deposited «.

Pig. 6 and 7 show that the uniformity of a phosphorus-containing nickel coating deposited from the same bath does not change if the bath contains different amounts of iron (II) ions instead of different amounts of iron (III) ions contains.

Pig. 8-10 show the gradual improvement in uniformity a 3 phosphorus-containing! tickel coating, which is deposited from a strongly acidic bath, the one high Content of iron (III) ions and that for the reduction of iron (IIl) ions to iron (II) ions finely divided Iron is added in increasing amounts.

With the continuous deposition of phosphorus-containing ITLckel on iron substrate in the areas indicated in Table T. Bathing has been shown to be with advancing Working time per. Unit of time deposited amount gradually decreased, as did the evenness of the coatings obtained, and that finally the abaoheeting ceased completely, although the composition of the bath by fortifying it with the necessary beaband barking essentially konotnntgohaibün was, and that one also wakes up such a band tinem nicab made of iron boo handily Subübrab no usable received phosphorus-containing ITickolllborzug, could.

009349/172 1

BATH ORIGINAL

It has been shown that the aforementioned difficulties due to the enrichment of the bath with iron (III) ions derived from the ferrous substrate to be coated in the bath and for example consists of iron and steel, for example from such a substrate that of the suspension device fell down and remained on the floor of the bath »The baths indicated in Figo 1 have · have a high degree of acidity, so that they dissolve the iron in the substrate as long as it is not completely coated is. ■

The increase in the iron (III) ion content of the bath leads to a deterioration in the quality of the coating, e.g. B. in terms of the evenness of his Thickness.

Using a test procedure carried out in a Hull cell therefore became the relationship between the content of iron (III) ions and the current density in a starting bath investigated, to which iron (III) ions were added. That The initial bathroom had the following composition!

NiSO ₄ .6H ₂ O 150 1 eA NiOl ₂ .6H ₂ O 150 g / i H ₃ PO ₃ 20th g / i H ₃ PO ₄ 85 g / i pH-Y / ert, with UaOH
set"

00 98 49 / 1.7 2 1

Purely this investigation resulted in four out of five initial, "contain iron (III) sulfate of the above composition added as iron (III) ion source in amounts of 2 g / l, 6 g / l, 12 g / l and 22 g / l, respectively. In the on Baths produced in this way were made of sheet brass test pieces of 100 65 χ 2 mm of a lempera * - door of 70 ° C and a current density of 1 A / dm, so that phosphorus-containing hickel is deposited from the bath became. The investigation showed that the amount deposited per unit of time with increasing content of the bath of ferric ions decreased, as can be seen from FIGS. 1-5, in which the hatched area 1 is an uncoated area and the area 2 is a coated area represents.

In addition to the above tests with a Huil cell further tests were dmrehge for coating formation * · fühftV '' ³ '''■"■''

In an 'experiment test pieces of the above Art one by one immersed in a bath which had the following composition and among the following Conditions were operated

ITiSO ^. 6H ₂ O 150 g / l 1 Ni oil ₂ .6H ₂ 0 . 150 g / l 70 ° C H ₃ PO ₃ 20 g / l 5 A / dm ² H ₁ PO.
3 4 85 g / l PH value 'Bath temperature Cathode ray density

009 849/1721

2,026 * 08

- 12 - ■ '

This bath was IPeCl-, increasing in. ! Bergen, added ».-. If, the bath 20 g / l PeOl-> contained would be from the lad No more phosphorus-containing nickel deposited on the test item, compartment with the addition of 7 g / l finely divided iron to the bathroom the separation took place again like Im dem original bath that did not contain FeCl-. *

A second experiment was carried out in the same way as the · ■ '- ■■ - given above, but with a bath _r the Mm after; standing composition had and under folgeiide®. ledi: n

_4, 6H ₂ O 150 g / l

WiOl ₂ , 6H ₂ O 100 & Λ

H ₃ FO ₃ W) ^ A

H ₃ PO ₄ 85 g / l

pH value 1.

Bath temperature 70 ° tJ
Cathode current density 6 A / dm

In the process, ^ "(SO *) ^ was added to the bath in increasing amounts. With a content of 22 g / l Fe ₂ (SO ₄ K in the bath, the" deposition of phosphorus-containing nickel ceased ") after the addition of 5 g / l finely divided iron, the separation was carried out • as in the original bath,

A third attempt was made as was the second Experiment »but with a bath having the following composition and under the following conditions became

009849/1721

2Q26406

NiSO..6HpO 250 g / l 1 NiCl ₂ .6H ₂ O 150 g / l 70 ° ö H ₃ PO ₃ 70 g / l 6 A / dm ² 85 g / l PH value Bath temperature Cathode current density

Increasing amounts of Fe ₂ (SO ^) ^ were added to the bath. At a content of 20 g / l Pe ₂ (SO, K, no more phosphorus-containing nickel was deposited from the bath. After the addition of 5 g / l finely divided iron, the deposition took place again as from the original bath.

Another test was carried out the same as that described above, but instead of the four baths with a content of iron (III) ions five baths with a content of iron (II) ions are used. These five baths were made prepared by starting baths of the composition given above iron (II) chloride as a source of Iron (II) ions in an amount of 2 g / l, 6 g / l, 12 g / l, 22 g / l or 100 g / l added. The second investigation showed that the presence of the iron (II) ion has no effect had the deposition of the phosphorus-containing nickel. this can be seen from Figures 6 and 7, in which 2 shows a covered area.

These two sub-bookings show that the presence of iron (IEI) ions in the baths has an adverse effect on the deposition of phosphorus-half nickel

009849/172

the baths, while iron (II) ions have no such influence. The presence of iron (II) ions is unavoidable when coating ferrous substrates in strongly acidic baths according to the present invention. It has now been found that this disadvantageous influence is eliminated and the amount deposited per unit of time is restored can be brought to the normal value if you have a bath in which iron (III) ions have formed, finely divided Iron adds *

In the bath with a content of 22 g / l iron (III) sulfate was initially reduced, per unit of time from £; s; 3chiedene Amount increased again to the normal value, womi die Amount of finely divided iron added to the bath with a grain size of 2-3 micrometers from 1 g / l to over 3 g / l 7 g / l was brought »The cause of this effect is not exactly known. It is believed, however, that the effect is due to the fact that the rapid reaction causes 3wi3chan the finely divided iron and the bath added with it, the egg (III) ion with the formation of nascent hydrogen is reduced to the Eiseri (II) ion. This is in the figures 8-10, in which 1 denotes a non-overexcited area and 2 denotes a coated area »

In the practice of the invention, the The bath used to form a coating is mixed with finely divided iron if the amount deposited per unit of time is infoli; y the formation or occurrence of iron (IIl) ions in the Bad has fallen dramatically.

The naoiia bun.-Melon Αλ ι nutritional objects facilitate understanding d - !. j ürL'iti iiui ^ ag

0080 * 8/17 ί I BADOBiGlNAU

Examples 1 - 28 . .........., - ■ .- ■. '. * ■.

Me'hrschiehtige! Metal coatings according to the invention.) Beneath the outer layer had a layer of phösphorhal ¹ -tigern nickel were formed on pieces of polished "steel sheet with the aid of a bath to form a coating of phosphorus liiekel and other baths to form metal coatings - »The operating conditions corresponded to the specifications of the 3}: abell« 3% 3D! «Products, ie the sheet steel pieces with the multilayered metal coating, were subjected to a load cycle according to 1ΒΦΜ.Β to test for resistance to sion The results of this test are shown in Table 4-.

For comparison, additional pieces of polished sheet steel were used of the type indicated above with a customary multilayer metal coating which does not contain any phosphorus "· containing Niekelschicht according to the Irfindung possessed * thereby some of the 'nickel plating baths have also been among the in the conditions specified in Table 3 operated »The Pieces coated in this way were then tested for corrosion resistance in the manner indicated above Results of this test are also in the table specified

009849/1721

3-

Composition of the galvanic. Beater, and.

Bath-
B: e3t.andteile
and
Characteristic values * ■ 55-60 290-310 ί 260-320 I. mm - j ■
ί eat
■ i
I. NiSO ₄ ^ oH ₂ O, g / l 280-300 H ₃ BO _3,. g / l I 30 '-40 4-5 40-45 t 52 -75 I. i t 40 -50 H ₂ SO ₄ , g / l : j
! - ' GuSO. * 5Hu0, g / 1 pH value, f
represents with ifeOH j I. CrO ₃ ,, g / l pH value, - [
set with
HiGO ₃₁ H ₂ SO ₄
Bath temperature, ⁰ G; ; 45 -50 t lTi (S0 ₃ liH ₂ ) _2i , g / l Katko den-
current density
A / dm ² j 3f7? -41; j H ₃ PO ₃ , g / l \ 50 = ' I m H ₃ PO ₄ , g / l 131,6-4, 3
; 50-61 in the | 4-5 : 3 ^ 0-3 ^ 5
l 55 * 65 L. u ■ m ; 5-aO *

009849/1721

It is

A a bright nickel plating bath with the following additives »

Mr. 63, 10 ml / l No. 610, 5-10 ml / L,

B a semi-bright nickel plating bath with the following additives »

2N, 0.6 - 1.2 ml / 1 U, 0.6 - 1.2 ml / 1 ■ Mr. 62, 2-5 ml / l,

C a hard nickel plating bath with the following additions

ι ■ ■

DN-30, 7 ml / 1

DN-303, 15 ml / 1. ■

DN-3O5P, 20 - 25 g / l DN-307, 0.5 - 2.0 g / l,

D an acidic blank copper plating bath Udylite UBAO with a Addition of 5-7 cm ^ / l UBAO No. 1,

E a Sargent chrome plating bath,

a sulphamic acid nickel-plating bath with the following additives:

No. 2 :

»R. 63

No. 610 and

G an effective bath for the formation of a niocel coating a with a low phosphorus content of 5 ^ *

AUt additives were a product of the Udylite Corporation in USA.

009849/1721 '

Table 4

Corrosion resistance of multilayer metal coatings when determined by a test cycle according to ASTM 3 380-61T:

Designation
tion of the
received
more layers
term metal
coating Thick
of
DB e de
Above
G re
TO £
A. inc
;it
F. el
η
\ j layers
E. total
thickness of the
nickel
schich
ten of the
Over to
total i 10 Corrosion
resistant
speed, ...
Application
number Control
examinee 20th 1 10 10 0 * 25 12th 5 2. 10 20th 0.25 22nd 9 3 10 10 2 0.25 ö 4th 10 20th 2 0.25 5 9 example 10 1 10 5 0.25 20th 6th 2 10 10 0.25 7th 3 10 20th 0.25 12th 9 4th 10 2 5 0.25 17th 9 VJI 10 2 10 0.25 8th 9 6th 10 2 15th 0.25, 13th 9 7th 10 3 5 0.25 18th 9 8th 10 3 10 0.25 8th 10 9 10] 3 15th 0.25 13th 9 10 10 3 5 0.25 18th 9 11 10 3 10. 0.25. 7th 9 12th 10 3 15th 0.2.5 12th 9 13th .2 5 0.25 17th 6th 14th : ■ 2 10 0.25. - ■ :, .6 15th 2 15th 0.25 6th

0098.49 / 1721

Table 4 (continuation) ";

Reference:
tion of-
received
more layers
term metal
coating. Bio
d.B'3 ke
P.
B. de
at
JC τ- e
train
Λ Inc
■ it
J el .nen layers
i Total-
d; icke der
Igelit des : T - "- - ■ ' 16 - " 3 5 0 _f 25: ; 8th 1-7 3 10 QV: 25 | 13 ^: '. , t - - ■; ■■■ to 3 15th 0 ^ 25 'm '"■;. ■ i s 19th 5 5 0 * 25- to is 20th 5 10 0 ^ 25 "M - ■ I s 21; VJl 15th Q «25 20th i & 22nd 3 VJl a _r 25 §: - 23 . 3 10 ■ 0 * 25 '■ -__ tJ i ^ ■ ■ ■■■■ ■■ '- 24 : 3f $ 5 0, _f 25 1; 8 j % 25th ΐ5 VJl 0> 25. ■ ^j 20 26th t5 ! 5 % 0 ^ 25. 22nd 27 10 ί 5 _O; 25th 20th 28 10 f ⁵ ; 2 0.25 22 ■ "

File were the SchI hurries en · Ä ~ & in ä- ^ei i roi'b ö.sja letters be sei Glittet en baths after; Table 3: deposited »,

From Table 2 it can be seen that in the examples · 1; - 28 · metal multilayer coatings described according to the Erflncang which have a content of 5 $> Phoaphor below the Außensehicht a Iiiekelsciiicht under supply of tie together the thick ^one Nicke la chi cht en the mehrseliichtigen

009 & 49/1721

BATH

2026408

a hö '& ere EorrosionsbesMndigfceit the itontrollprüfllnge 1 - understands 4' Is - check that melirseMcntige metal coating ass according to the ^{Irfindiämg::} -. ■ a AußensaMeht and at least one 'under derAußen "splints lying Sehielit is" At eisernder in de »l' aiaelleii 2 and 4

nisse erJceimt mau ferae-r, aass a ptosj) 2iO3?33.altlg@2? ülDeraug, as he in the $ afcaHe 2 aiigeg ^ teaj .3-01; / "· ιτ © 3? 1ί © 1» '! · "- · -" - ■ -Yes, in-a melsrscMciatigen one' under the AuiSenaeMcM . beatekt lying is as angegetoes in IBaibelie 4 ig * ;, einseiiielitigen a © in the form OB animal ^ uges, the au laali'igem liekel and annänernd same Dietee hat like the mehrseMentige MetalXäberaiii;., w-ei iu? the 't seMentigen metal plating the the
-improving effect degs
a corresponding spiergistic kit is supported by other metal elements of the menrs.etoicötigen jfctallüber · over. "

From Table 4, for example, Jiervo.r. Shows that the small metal coatings that are extracted from the 10 micrometer thick, 2-3 micrometer thick nickel pliosplxorlialtigen and the 3 micrometer thick bright nickel * - or from de © 0U. Iiickelseliiclit deposited in the aminic acid jad, whereby the kicked ones on the ö-i'U] ⁱ dwerkstoi'i 'were formed in the given order. Examples 4, 7 and 10), annually left the same corrosion resistance ^ vie di.e |] over! 2Üge from the 20 läikrometcr thick blank nickel boliclite and the 2 meter thick liartnickelskliicöt (see control test item 4)

009849/1721

. / - ν ·. · ORIGINAL BATHROOM

Examples 29-35

Pieces of polished steel sheet were made in the same way coated as in Examples 1-28 and subjected to one to four test cycles according to ASTM B 380-61T.

For comparison, pieces were made from the above Steel sheet provided with a customary multilayer metal coating which does not have a phosphorus-containing nickel layer according to the Invention owned. Some of the nickel-plating baths were operated under the conditions given in Table 3.

00 9849/1721

Table 5.

Corrosion resistance of multilayer metal coatings when determined by 1-4 test cycles according to ASiPM B 380-61T-

Designation
tion of the
received
more layers
term metal
coating thickness
of t
D. i the
"b.evzi
B. one
ü.ge.s ■
G üelnei
A. ι Sc
G not en Total-
thickness of the
Nickel-
layered
ten of the
Over- "
ges; -. Corrosion
resistant
ability
number
after
1/2/3/4
Test cycles 9/6/3/3 Control
examinee - 9/7/4/4 VJl 10 20th 2 0.25 22nd 9/7/4/4 6th 10 35 2 0.25 37 10/10/8/8 7th 10 15th 5 2 0.25 22nd 10/10/8/5 8th 10 25th 10 0.25 35 9 10 25th 10 2 0.25 37 9/9/8/8 example 10/10/10/10 29 10 3 5 0.25 8th 9/9/9/9 30 · 10 3 10 0.25 13th 10/10/10/10 31 10 .3 15th 0.25 18th 10/10/10/10 32 10 3 20th ^! 0.25 23 9/9/9/9 33 10 , 5 5 0.25 10 '9/9/9/9 34 10 5 10 : O, 25 15th 35 10 15th 0.25 ■

The designations A, B, 0, D, E, G for the layers of the coatings have the same meaning as in Table 4 »

The test results given in Table 5 show the following »

0 = 19 * 143/1721

When testing according to ASiEM B 380-6 VS. The number of multilayer metal coatings which contained a phosphorus-containing IJiekelschiclit "increased with increasing: ?? - Jiiizah YOE test cycles, while this was the case with the coatings * which had a phosphorus-containing layer, with the exception of the coating according to Example 29 * Case was, although for them, the total thickness of the wrap sleeves was smaller *

2 »In multilayer metal coatings, under the: * Issen ~ Ä layer a phosphorus-containing Hickelsehieht in a thickness of 3 · -'5 micrometers had ₉ sufficient außei this one Äußenschieht from Blank nickel, Dasit the coatings -a ■ faultless appearance" and a have sufficient corrosion resistance ". It is therefore sufficient if the amount of coating in the coatings according to the invention is one third to one-half of the amount of mica in the" usual coatings "*

3 · "The e:; .- rindungsge: mäj3e method may old lower .Number be performed by steps than the usual, ind method of forming multi-layer metal coatings which a semi-bright Uicke layer _s a Blankiiickelschicht a.!... Have hard nickel plating, or a semi-bare pebble layer, an Udylite tri-not and a blue-li - uickelsciiiclit "- the last two metal plating - ^ ■ are regarded as the best hickel overlays. And before £ -, 11 em used on L'raftfaiiraemgteile *

"Our ei: si.:ri)j,iJ i.ge nickel-plating pieces of the .above .. an £ Oi / 3bener: / ä-1.- auö polishedia Stalilblech at 90 ° ö, M, t eiiit-3-:; Kiki ^ or.eter thick phosphorus against hickelschicht ubcii '^ oßi-.L. The ternioculation rii ^ ~ Ii '; -verweixAet, which under the Beaeiehnunr

9849/1721 _DAn

BATH

from the Japanese Sirma Hih © n:

will * "The same llech« ätuek @ were thus ffli ^ -lfelfβ "of the A with a 5 micrometer die; with the help of cfes Bades 1: with & inö: i "© _fc 2 coffin nt -ölirömsctoicht überzxjgeii, *: Bf e luiig-useiie l ^ sttiig" tefeire 'foigend'e became miter. tia & listeüsn-de &

Hennwart

25 g / in - "

pH-1 ert _#
set

90 ^a

Unit of time ^ ^ kronts-Eer in iä

In this way he meets etirofitless föüniLe-ke-lüiig; & η £ Bleeiistttßk formed ,, meiaiaoMoibtige MGkelüiie-paiig 8 GewicMöproiaent Biospliöa? "The i0 & rzogßimtk pieces a bilfaycl according to ASiM B 38Θ-61Ϊ untet» iroa? iim teniu there is no corrosion resistance rating

On zinc, cells are formed in the same way as on bidding. In ditseffl case, before the formation of the nicety, a coating is usually formed

00 9 849/17 21

Examples 36-44

Zinc sheet metal pieces of 50 100 χ 1 mm were used in the Coated in the manner described above. Then the coated pieces were put to the test for corrosion resistance in a test cycle according to ASTM B Subject to 3ÖO-61T. For comparison, the same pieces of zinc sheet were used provided with a customary multilayer metal coating which did not have a phosphorus-containing nickel layer. Some of the nickel-plating baths operated under the conditions given in Table 3 were used became. The coated pieces also became the Tested according to ASTM B 38O-61T. The results of the Tests are shown in Table 6.

009849/1721

Table 6

Corrosion resistance of multi-layer overlay on zinc plates when determined according to ASl ¹ MB 3öO-tiT (1 test cycle)

Bezexch- Thick ciei • ■ 10 ^% individual G i 3 > 3 A. α layers ■ (le velvet - Corrosion tion of the of Coating 2; thickness of the resistant received 10 10 3 : · 0.25 Nickel- ability (Be several times, 1 5 shi-ch- rating term metal 10 10 2 10 · 0.25 ten of the and host coating D. B. E. Exactly picture ¹ mg) 10 10 ¹ 3, 10 2 0.25 ge s Control 10 i Is examinee 10 20th 0.25 10 10 i 10 8, grayer 10 ¹ 5 20th 2 0.25 rust 11 10 12th 9, finer 10 5 0.25 gray rust 12th 20th 9, finer 2 gray rust 13th 10 0.2.5 22nd 9, finer gray rust H 10 15th 5 0.25
* 20th 9, finer gray rust 15th 15th 10 0.25 22nd 10, finer gray roat example 15th 0.25 36 7th 9, finer 5 blue roat 37 12th 9, finer 10 blue roat 38 17th 9, finer 15th blue rust 39 3 8th 9, finer blaiur R ο 3t to 40 5 13th 9, finer 0 » 0.25 blue rust * ■ »
approx 41 10 18th 8th 42 0.25 8th 3, finer • ο 0.25 blue rust ISJ 43 10 9, finer 0.25 blue roat 44 15th . 10
■ * ■ & _ ^^. rHk - ■ - «All It 0.25

The designations A »B, ö. ,, Ό» E * S for the ^: Sohiektea the coatings have-π äie-the same meaning as in. Deiv Hüäfeelie; - '' 4 ·

".Me more cliicIitigen metal coatings on the 2in.ksu% strat tended:,: ar formation of fine leren *. Hur two metal coatings (examples' 41 -juiö: 44); -. Prevented ij & dea sost / ea of the substrates * /. . .-

Aha aen substratum ■ ». the, one

possessed a phosphorous © - iTicfkeisßhißh-t optionally formed a blue t:. ost _r wäiireiLä && £ - »substrates: the vrärde rust formed with a metal deposit üblioheii tiaras» .- a gray * Mti && ¥ ■■ of gray Hoste3: you can see * that the ginkrost duröii. ύ, & η. ^ Εβ-tall überäu-g 'was visible through ^ A blue lips te s indicates ^ -that the boat en des Substrate tiööü nieiit b..e. "_f; goimem. Has"-. l) ia "cli application, a erfindungsgefflsßem;? · ffiel3 s- © Me3a"<t strength -Hetallüber eye s canoe daher.ein diecast aas Mnk 'a äüsgeaeiclinete KorroB;.. get ion.äbes * * tändigkeit.

Formation of a coating on a synthetic resin * ..

A coating is thereby formed on a synthetic resin. _{> s} - that. On which a thin copper Munstharz zimäciist ohemisch ¹ "barren ■; ■ '■ _ niokelscJiicht is formed ,; so that the substrate is electrically conductive, and to complete the formation of the coating on the jars an electric current is passed through the thus formed.

Examples 45 - 50 ■ ■ -. _:

■ ßücI-3 (oo r. 13O ₁ .5: 3 mm) from ABü ~ H.% rz, das'von the gapaniachen Si ro na Uk; Saigon Corporation below;? - outside Beseichiiüng ^M Saikolac EP ⁰

00-9849 / 1721 f bad original

2026 A 06

were supplied chemically in the usual way coated with a plucked layer and then coated with nickel layers as shown in Table 7, The coated pieces were subjected to a test cycle according to ASTM B 380-61T to test for corrosion resistance. For comparison were Similar pieces are provided with various customary multilayer metal coatings and then a test cycle Subject to ASTM B 38O-61T. The results are given in Table 7 »

009-849 / 1721 '-'. 'original inspected "

Table 7

Corrosion resistance of multi-line metal coatings on plates made of ABS resin when determined according to ASTM B 38O-6IT (one test cycle)

Designation
tion of the
received
more layers
term metal
coating The ice
of
D. : e de3
Above:
B. c eir
suges
G LZ one
ι
A. in Sc
σ jhichten
E. total
thickness of the
Hickling
layered
ten of the
Over to
total Corrosion
resistant
ability,
Valuation
number Control
Test item 16 10 10 0.25 10 8th 17th 10 10 2 0.25 12th 10 18th 10 20th 0.25 20th 8th 19th 10 20th 2 0.25 22nd 9 20th 10 15th 5 0.25 20th 10 21st 10 15th 5 2 0.25 22nd 10 example 45 10 2 5 0.25 7th 9 46 10 2 10 0.25 12th 10 47 10 2 15th 0.25 17th 10 48 10 3 5 0.25 8th 10 49 10 3 10 0.25 13th 10 50 10 3 15th 0.25 18th 10

The synthetic resin substrates used do not rust, of course, but the copper layer can corrode with verdigris on the surface and the corrosion can continue, so that the multilayered metal coating containing the copper layer becomes detached from the synthetic resin substrate when the metal surfaces formed on the plucked layer become detached be corroded.

009840/1721

From Table 7 it can be seen that the invention multilayer metal coatings as well as iron, die-cast parts made of zinc and the like also on substrates Synthetic resin can be used with very good success,

Metal coatings applied to synthetic resin substrates must be adherent. This requirement is difficult to make. meet _o With a multilayer metal coating according to the invention on a synthetic resin substrate, however, just as good results were obtained in a bending test to determine the adhesive strength of the coating or the temperature change test as with conventional coatings on metal substrates «,

Example 51

Multi-layer metal coatings according to the invention, which instead of the phosphorus-containing nickel layer is a layer of phosphorus-containing Cobalt were made as follows:

Pieces (50 100 χ 0.3mm) of polished sheet steel were made in an acidic bath with a 10 micrometer thick bare copper layer, furthermore with a 5 micrometer thick layer of phosphorus Cobalt layer, a 5 micrometer thick layer of bright nickel and a 0.25 micrometer thick layer of Sargent chrome overdrawn. The baths used for coating formation were used under the conditions given in Table 3. The bath used to deposit phosphorus-containing cobalt had the following composition and was under operated under the following conditions:

009849/1721

CoSO.o6H ₂ 0 250 g / l H3PO3 40 g / l H ₃ PO ₄ 100 g / l PH value 1 Bath temperature 60-7O ⁰ O Eat ho denst r omäi clit e 50 A / dm ² anode carbon

The phosphorus-containing cobalt separated from this bath contained 3> 8 percent by weight phosphorus and had a uniform gloss _o

Those provided with the aforementioned multilayer metal coating Pieces of sheet steel were subjected to a test cycle according to ASTM B 380-6II. They showed a satisfactory one Corrosion resistance according to the rating number 9 < >

Used to form a phosphorus-containing eobalt coating one preferably has a bath that has the following composition and is operated under the following conditions »

00SO ₄ .6H ₂ O 200-300 g / l

H ₃ PO - 30-50 g / l

H ₃ PO, 60-100 g / l

pH 2 or less

Bath temperature 50 - 80 ° 0

Cathode atom density 4-0 - 60 A / dm ²

009849/1721

202Θ40Ι

Example 52

Pieces of polished steel sheet were laminated with a Metal coating provided, which instead of the phosphorus-containing cobalt layer used in the example, a layer a phosphorus-containing nickel-cobalt alloy. The procedure was as in Example 51, but instead of the bath to form the phosphorus-containing cobalt layer, a bath to form the layer of the phosphorus-containing nickel-cobalt alloy used This bath had the following composition and was operated under the following conditions:

150 g / l

0 OCl ₂ .6H ₂ O '18 g / l

, 35 g / l 2.5 g / l 50 g / l

H ₃ PO ₃ 45 g / l

pH 0.7

Bath temperature 50 ⁰ O

Cathode current density 10 A / dm ²

Anode carbon plate

The pieces provided with the multilayer metal coating in the same thickness as in Example 51 became one

"Subject to test cycle according to ASTM B 380-61T · The results show that the metal coatings have! Corrosion · * had resistance corresponding to the rating number 10 and

«Their shine remained unchanged.

009849/1721

Which consists of a phosphorus-containing Niokel-Eobalt-Legierurig layer of the multilayer metal coating contained 45.0 $> nickel, cobalt and 5.3 # 49.5 ° i phosphorus by weight.

ORIGINAL INSPECTED

009849 / tm

Claims (1)

Patents / 1 β] Corrosion-resistant multilayer metal coating a metallic or non-metallic base material, characterized in that the coating has, under its outer layer, a layer made of phosphorus-containing Nickel, phosphorus-containing cobalt or a phosphorus-containing one Nickel-cobalt alloy and has been produced in a galvanic or electroless plating process is. · 2. Metal coating according to claim 1, characterized in that the 'phosphor-containing' one arranged under the outer layer Layer contains 1-10 weight percent phosphorus 3. Metal coating according to claim 1, characterized in that that the phosphorus-containing one arranged under the outer layer Layer has a thickness of 3-5 micrometers " 4-β process for the galvanic formation of a corrosion-resistant multilayer metal coating on a metallic or non-metallic base material, the metal coating under the outer layer a layer of phosphorus-containing Nickel owns, dadurah marked that the layer of phosphorus-containing nickel arranged under the outer layer is formed in that phosphorus-containing nickel Nickel is deposited from a bath which has the following composition and is operated under the following conditionsi 009849/1721 ' NiSO ^ .6H ₂ O 100 - 300 g / 1 Kici ₂ "6H ₂ o; 50 - 200 g / 1 E ₃ PO ₃ 20 - 100 g / 1 H ₃ PO ₄ 50 - 100 g / 1 PH value 2 or less B ad t e mp er at ur 60-8O ⁰ C ! vat ho den current density 3 - 10 A / dm. - Process for the galvanic formation of a corrosion-resistant multi-layer metal coating on a metallic or non-metallic base material, the metal "metal & coating under the outer layer having a layer of phosphorus-containing cobalt, characterized in that the layer of phosphorus-containing cobalt arranged under the outer layer is formed in that phosphorus-containing cobalt is deposited from a bath which has the following composition and is operated under the following conditions:
CoS0 ₄ o6H ₂ 0 <200 - 300 g / l H ₃ PO ₃ 30 .- ■ 50 g / l H ₃ PO. 60-100 g / 1 pH 2 or less Bath temperature 50-80 ⁰ C 2 cathode current density 40-60 A / dm 6. The method according to claim 4 or 5, characterized in that the base material to be coated is a material based on ν iron, for. B. Elsen or steel and with a decrease in the amount of phosphorus-containing metal deposited per unit of time due to the formation of iron (HI) ions * ^: 009849/1721 from the iron-based material the bath finely divided iron to increase the reduced, per unit of time deposited amount is added. 009849/1721 COPY