CN1307648A - Coating composition comprising nickel and boron - Google Patents

Abstract

The present invention relates to an electroplating process utilizing a coating bath that provides a hard, abrasion and corrosion resistant, tough coating on a substrate, said coating bath having a pH of from about 10 to about 14 and comprising nickel ions in an amount of from about 0.175 to about 2.10 moles per gallon of the coating bath, (2) an effective amount of lead tungstate to stabilize the bath and form a continuous coating free of specks, without any significant deposition of lead tungstate in said coating, (3) an effective amount of a metal ion complexing agent in an amount sufficient to inhibit precipitation of said metal ions from the coating bath, and (4) an effective amount of a borohydride reducing agent.

Description

Coating composition comprising nickel and boron

This invention is a continuation-in-part of US Patent Application Serial No. 09/074703 (filed May 8, 1998).

Background of the invention

The present invention relates to novel metallic coatings with exceptional hardness. More specifically, the present invention relates to metallic coatings comprising nickel and boron, and the reductive deposition of said coatings from aqueous solutions on the surface of substrate articles at alkaline pH values.

It is well known in the art to electroplate or deposit metal alloys by chemically or electrochemically reducing metal ions on the surface of an article to modify its surface properties for decorative and functional purposes. Of particular commercial interest is the deposition of metal/metal alloy coatings on metallic and activated non-metallic substrates, which enhance surface hardness as well as corrosion and abrasion resistance. The hardness and corresponding wear resistance of nickel-boron and cobalt-boron alloy coatings are recognized in the art. Patent literature indicates that there is ongoing research and development in the field of nickel-boron coatings to produce harder, more corrosion-resistant coatings. See, for example, US Patents 5,019,163, 3,738,849, 3,674,447, 3,342,338, 3,378,400, 3,0453,342, and 726,710. It is known in the art that harder coatings can be obtained if borohydrides are used in nickel/boron plating baths. But borohydrides are very unstable in this bath. The solution to the stability problem is to add stabilizers such as thallium sulfate or lead chloride. The addition of stabilizers can hinder the formation of nickel coatings, thereby adversely affecting the hardness of the coatings. According to the present invention, since the stabilizer is not co-deposited in the coating, the nickel coating is significantly harder than described in the prior art.

Nickel/boron coatings hitherto always included a stabilizer as a third element. The only exception is dimethylborane paint. This paint has no stabilizers present in the paint. The application of this method is very limited because the deposition rate of the bath is very slow and the coating is very thin. The deposition rate was on the order of 0.00015 inches/hour. The deposition thickness is limited to about 0.0001-0.0002 inches. These deposits are too thin to be used on abrasive surfaces.

It is therefore an object of the present invention to provide an article coated on at least a portion of its surface with a hard, ductile, wear-resistant coating comprising nickel and boron by reducing the adverse effects due to co-deposition of stabilizers. and corrosion-resistant metal coatings.

Another object of the present invention is to provide a coating bath from which a hard, ductile, abrasion and corrosion resistant coating can be deposited on at least a portion of the surface of a metallic or activated non-metallic substrate.

Summary of the invention

According to the present invention, there is provided a novel metal coating composition comprising both nickel and boron and lead tungstate. The coating composition may contain other metal ions, such as cobalt. The coating composition is particularly useful for deposition on the surface of an article which is exposed to corrosive conditions or which is in sliding or frictional contact with another article under abnormal wear and bearing pressure. The metallic coating composition of the present invention comprises about 67.5-97.0% by weight nickel, about 0-48.5% by weight cobalt, and about 2.5-10% by weight boron. Cobalt can replace nickel up to about 50% nickel. The substitution of cobalt for nickel is preferably less than 25% nickel. The preferred range for the nickel coating is 94-97% by weight nickel and 3-6% by weight boron. The coating is visibly hard and ductile, yet very resistant to corrosion and abrasion.

It has surprisingly been found that by using lead tungstate to stabilize nickel-boron electroplating baths, it is possible to form nickel/boron coatings with even higher hardness than previously obtained. Stabilizers are routinely added to these electroplating baths to delay the precipitation of reducing agents in the coating bath itself. These stabilizers are co-deposited with the nickel paint. This co-deposition inhibits the complete formation of the nickel coating, thereby limiting the hardness and wear resistance of the nickel-boron coating. It has been found that the hardness of nickel/boron coatings can be increased by substantially inhibiting the co-deposition of stabilizers. According to the present invention, lead tungstate is precipitated as particles in the electroplating bath rather than being co-deposited in the coating. These particles can be removed by trapping the particles in the filtration system.

The coatings of the present invention are preferably prepared by contacting the substrate with a complexing agent comprising nickel ions, lead tungstate ions, metal ion complexing agents, and borohydride reducing agents at an elevated temperature of about 180-210°F at a pH of about 10-14. The coating bath is in contact with the chemical applied to the substrate. After initiating plating in the temperature range of about 180-210°F, the coating can be plated at lower temperatures.

Detailed description of the invention

Substrates suitable for chemical deposition are those with so-called catalytic chemical surfaces, including those made of nickel, cobalt, iron, steel, aluminum, zinc, palladium, platinum, copper, bronze, chromium, tungsten, titanium, tin, silver, carbon, Those composed of graphite and its alloys. These materials act catalytically to reduce metal ions in the electroplating bath by the borohydride, resulting in the deposition of metal alloys on the surface of the substrate in contact with the electroplating bath. Electroplating of aluminum generally requires a protective discharge coating to prevent dissolution during plating. Non-metallic substrates such as glass, ceramics, and plastics are generally non-catalytic materials; however, these substrates can be sensitized to be catalytically active by producing a film of catalytic material on their surface. This can be accomplished by various methods known to those skilled in the art. A preferred method involves immersing a glass, ceramic or plastic article in a solution of stannous chloride and then contacting the treated surface with a solution of palladium chloride. In this way, a thin layer of palladium is reduced on the treated surface. In accordance with the present invention, the article may then be electroplated or coated with a metal composition by contacting a coating bath, as detailed below. It should be noted that magnesium, tungsten carbide and certain plastics have some deposit resistance to the coatings of the present invention.

The coating bath used for deposition according to the invention comprises:

(1) Nickel ions, about 0.175-0.210 mol/gallon. Based on nickel chloride range of 0.05-0.6 lbs/gal. The preferred range for nickel ions is from about 0.35 to 1.57 moles per gallon based on 0.1 to about 0.45 pounds per gallon of nickel chloride.

(2) Cobalt ions, up to 1.05 moles per gallon but not exceeding 50% nickel in the bath;

(3) an effective amount of a chemical agent for adjusting the pH of the bath to about 10-14;

(4) metal ion complexing agent of about 2.26-6.795 mol/gal, preferably 3.3-3.8 mol/gal;

(5) About 0.01-0.8 moles per gallon of paint bath borohydride reducing agent, based on sodium borohydride, preferably 0.020-0.033 moles per gallon of paint bath.

(6) The lead tungstate stabilizer of effective amount, its scope is about 0.0143-0.30 gram/gallon, preferably about 0.0182-0.08 charge/gallon.

The borohydride reducing agent can be selected from known borohydrides having good water solubility and stability in aqueous solution. Sodium borohydride is preferred. In addition, substituted borohydrides may be used in which not more than 3 hydrogen atoms of the borohydride ion have been replaced. Sodium trimethoxyborohydride [NaB( _OCH3 ) _3H ] is an example of such a compound.

The pH of the prepared coating bath was about 12-14. Best results are observed if the pH of the bath is maintained within this range during coating, more preferably around pH 13.5. The adjustment of the pH of the coating bath can be carried out by adding any of various alkaline salts or the like. Preferred chemicals for establishing and maintaining the pH of the coating bath are alkali metal hydroxides, especially sodium and potassium hydroxide, and ammonium hydroxide. An added advantage of ammonium hydroxide is that the ammonium ions help complex the metal ions in the coating bath.

Due to the high alkalinity of the coating bath, metal ion complexing or chelating agents are required in the coating bath to prevent the precipitation of metal ions such as nickel and other metal hydroxides or other alkaline salts. Equally important, metal ion complexing agents are capable of reducing the reactivity of metal ions; complexed or chelated metal ions are least reactive with borohydride ions in bulk solution but can be catalyzed by substrates in contact with the solution. superficial reaction. The term catalytic surface refers to the surface of any article consisting of the aforementioned catalytic material, or the surface of a non-catalytic material which has been sensitized by applying a film of said catalytic material on its surface.

Complexing or chelating agents suitable for use in the present invention include ammonia and organic complexing generators containing one or more of the following functional groups: primary amino, secondary amino, tertiary amino, imino, carboxyl, and hydroxyl. Preferred complexing agents are ethylenediamine, diethylenetriamine, triethylenetetramine, organic acids, oxalic acid, citric acid, tartaric acid and ethylenediaminetetraacetic acid, and aqueous salts thereof. Most preferred is ethylenediamine.

Use about 2.26-6.795 moles/gallon of compounding agent per gallon of paint bath. This calculation is based on approximately 0.3-0.9 lbs/gallon of ethylenediamine. Best results are obtained if the paint bath is about 3.39-3.77 moles per gallon. This calculation is based on approximately 0.45-0.5 lb/gal of ethylenediamine per gallon of paint bath.

Metal ions, such as nickel ions, in the coating bath are provided by adding corresponding water-soluble salts to the bath. Any salt of those metals having an anionic component that is not resistant to the subject coating process is suitable. For example, salts of oxidizing acids such as chlorates are undesirable due to their ability to react with the borohydride reducing agent in the bath. Cobalt and nickel, chlorides, sulfates, formates, acetates, and other salts whose anions are substantially inert to the other ingredients in the alkaline coating bath are satisfactory.

Lead tungstate can be added to the electroplating bath from a concentrate containing pH regulators and complexing agents. The compounding agent may be selected from those mentioned above. A preferred complexing agent is ethylenediamine. The concentrate contains about 2-31 grams per gallon of lead tungstate. The preferred range for lead tungstate is about 7-12 grams per gallon. The concentration range of the compounding agent is 100-700 milliliters. The preferred range of compounding agent is about 300-400 ml. The pH of the mixture is above 8, preferably 10.5. The pH adjusting agent is selected from bases such as sodium hydroxide which are not harmful to the plating bath.

The concentrate is added so that, by dilution, the concentration of lead tungstate in the bath can range from about 0.0143 to 0.30 grams per gallon of electroplating bath. A preferred concentration range is about 0.0182-0.082 grams per gallon of plating bath.

Coating baths are usually prepared by forming an aqueous solution of the nickel and cobalt salts in appropriate quantities, adding complexing and stabilizing agents, adjusting the pH to about 12-14, heating to about 195°F, filtering, and finally adding the substrate to the Immediately prior to bathing, the required amount of sodium borohydride (usually in an aqueous alkaline solution) is added.

Articles coated or plated using the baths of the present invention are prepared by mechanical cleaning, degreasing, anodic-alkaline cleaning and finally pickling in an acidic bath according to standard practice in the metal plating art. The substrate can be masked as desired to allow deposition of the metal alloy coating only on selected surfaces. Although coatings of the present invention generally have excellent adhesion to suitably prepared substrate surfaces when paint adhesion is important or when some adhesion problem exists, paint adhesion can often be improved by The nickel discharge coating is enhanced by electrochemical deposition onto the substrate.

The coating process is initiated by immersing the cleaned or surface treated article in a hot (approximately 180-210°F) coating bath. The process continues until the coating deposition has progressed to the desired thickness or the metal ions have been depleted from the solution. Under the process conditions of the present invention, the deposition rate can vary from about 0.1 mil (1 mil=one thousandth of an inch) to about 1.5 mil/hour.

Preferred ranges for the composition of the electroplating bath include about 0.35-1.57 moles/gallon nickel, about 0.0182-0.08 moles/gallon lead tungstate ion, about 0.017-0.035 moles/gallon borohydride. The ratios of nickel, cobalt, boron and lead tungstate in the paint of the present invention can be adjusted by changing the relative amounts of metal salt components and borohydride in the paint bath.

In accordance with the present invention, under normal conditions of use of the coating bath, lead tungstate and borohydride reducing agents are added to the coating bath per hour in amounts corresponding to when they were used to prepare the bath. The need to supplement the coatings of the present invention with lead tungstate and borohydride depends on the ratio of coating bath volume to surface area to be coated. Therefore, it is generally not necessary to supplement the lead tungstate and borohydride to the coating baths of the present invention if smaller surface areas are to be treated.

A 1 gallon bath made in accordance with the preferred embodiment of this invention will coat approximately 144 square inches to a thickness of 1 mil. To achieve this result, the bath was replenished with lead tungstate and borohydride as these components were depleted from solution as described above.

The pH of the coating bath tends to drop during coating and should therefore be checked periodically to ensure that it is within the preferred range of about 12-14. It has been found that during the use of coating baths, any problems involving pH maintenance can be minimized simply by replenishing the borohydride content of the bath with an overbased (concentrated sodium hydroxide) solution of borohydride as needed change. The coating deposition rate for the chemical coating baths of the present invention is about 0.1-1 mil/hour and depends on bath temperature, pH, and metal ion concentration. At a preferred temperature of about 185-195°F, the rate of deposition from a freshly made coating bath to most metal substrates is about 1 mil/hour.

The practicalities of performing a chemical coating process are well known in the art. These processes are generally disclosed in US Patent 5,109,613 (issued to McComas on April 28, 1991), US Patent 3,338,726 (issued to Berzins on July 2, 1963), US Patent 3,045,334 (issued to Berzins on October 1, 1958), US Patent 3,378,400 (Stickles, issued May 16, 1968) and US Patent 2,658,841 (Gutzeit and Krieg, issued November 10, 1953), which are hereby incorporated by reference.

The electroless nickel coatings of the present invention have unprecedented hardness with concomitant abrasion resistance. They are very flexible to allow the coating to flex with the substrate while maintaining a strong bond to the coated material.

After depositing a nickel coating on a substrate, it is a common practice in the art to heat treat the coating to achieve maximum hardness. Prior to heat treatment, the Knoop hardness of the prior art nickel/boron coating is about 925. The Knoop hardness of prior art nickel/boron coatings is lower than 1373 after heat treatment. In contrast, by using lead tungstate as a stabilizer, the Knoop hardness of the nickel/boron coating before heat treatment is about 1000. After heat treatment, the Knoop hardness of the nickel/boron coating exceeds 1375.

The heat treatment is performed at a temperature of about 375-750°F for about 1-24 hours. For higher temperatures of about 550-750°F, shorter times of about 1-2 hours are preferred. At lower temperatures of about 375-450°F, longer heat treatment times are advantageous.

The structure of the nickel/boron coating changes upon heat treatment. Nickel and boron appear to be alloyed prior to heat treatment. After heat treatment, nickel boride is formed. This appears to be a dispersion of nickel boride within a nickel/boron alloy.

Coatings of any thickness can be obtained. Coating thicknesses from greater than 0.0001 inches to 0.01 inches or more can be obtained. Conventional wear coatings can be produced in a thickness range of about 0.0005-0.004 inches.

The coatings of the present invention have various uses, which are known to those skilled in the art. They are especially useful for coating the surface of articles that are subjected to high abrasion, friction, or sliding conditions under high temperature/pressure during normal use. These high wear conditions occur at many locations in tool structures, internal combustion engines (including gas turbines), transmissions, and a wide variety of heavy equipment constructions.

The following examples illustrate the bath compositions, process conditions, coating compositions and properties of the present invention in detail. The examples are given to illustrate the invention and should not limit the scope of the invention in any way.

Example

A 1 gallon batch unit of the coating bath was prepared as follows. For this example, four solutions were prepared: A (the bath), B (reducing agent), C (stabilizer), and D (bath supplement). First, 1 gallon batches of each solution were prepared. Solution A (the bath) consisted of deionized water, 0.2 lbs of nickel chloride, 0.5 lbs of ethylenediamine, and 0.33 lbs of sodium hydroxide. Solution B (reducing agent) consisted of deionized water, 2.5 lbs of sodium hydroxide and 0.8 lbs of sodium borohydride. Solution C (stabilizer) consisted of deionized water, 100 grams of sodium hydroxide, and 10 grams of lead tungstate and 400 milliliters of ethylenediamine. Solution D (bath supplement) consisted of deionized water, 0.6 lbs of nickel chloride, 1.5 lbs of ethylenediamine, and 1.0 lbs of sodium hydroxide (Solution D was the same as Solution A, but nearly anhydrous). Heat Solution A to 192°F: Wash two 1" x 11" stainless steel plates with detergent to remove oil and dirt from the plates. The plates were secured to steel wires and then placed in a solution of 30% HCl and 20% _{H2SO4 for} 60 seconds to activate the part. 10 mL of Solution B mixed with 10 mL of Solution C was added to the heated Solution A just before the plate was placed in the bath for plating. For solution C, 7-12 ml can be used.

After 30 minutes, solution A was titrated to determine the presence and amount of sodium borohydride. After each 30 minutes of plating, an additional 10 ml of solution B and 10 ml of solution C mixed together were added. Plating lasted 3 hours.

After 3 hours, the panels were removed from the bath and the deposited thickness was measured. Heat treatment was performed at 750°F for 90 minutes. The panels measured 0.0347 inches before plating and 0.0407 inches after plating, showing a total thickness increase of 0.006 inches or 0.003 inches per side, or a deposition rate of 0.001 inches/hour.

The sheets are continuous without any spots or porosity. These panels were then cut, mounted, cross-sectioned and checked for hardness following standard micro-thickness testing studies. The coating can then be examined for a profile representing the interface region between the coating and the substrate. This area is free of voids and foreign impurities.

The hardness of the coated panels was determined using a Knoop indenter with a 100 gram load. The hardness value before heat treatment is about 950-1050. The hardness values after heat treatment are as follows: 1545, 1685, 1610, 1785, 1660, 1710, 1690, 1820, 1730, and 1710. If you ignore the highest and lowest values and average the remaining values, you get a final hardness value of 1697. This shows that the novel electroplating composition produces reproducibly high hardness values. This value is at least 25% greater than other nickel-boron coatings of the prior art, thus clearly increasing the wear resistance by as much as 300%.

The remaining plated samples were analyzed using ICP techniques to determine the quantitative composition of the coating. ICP results (X-ray) indicated a composition of 95.5% nickel and 4.5% boron with a probable error of 0.5% trace elements. Before heat treatment, the coating is a nickel/boron alloy. After heat treatment, the coating has nickel boride dispersed in a nickel/boron alloy.

It has been found that heat treated coatings according to the present invention have a Knoop hardness value of about 1400-2200. These values are higher than the best hardness values previously given when coating nickel-boron chemistry.

The present invention using lead tungstate was compared to a prior art nickel plating bath using thallium as a stabilizer. In US Pat. No. 3,674,447 to Bellis, Example 3 results in a coating having a Knoop hardness of 900-1000 with 93% nickel, 3.5% boron, and 3.5% thallium. In US Pat. No. 3,295,999 to Klein, Example 2 results in a coating with 93% nickel, 4% boron, and 3% thallium having a Knoop hardness of 1000-1100. In US Pat. No. 5,109,613 to McComas, Example 1 results in a coating having a Knoop hardness of 1200-1300 with 90% nickel, 4% cobalt, 4% boron, and 2% thallium. The Knoop hardness of the Bellis and McComas coatings prior to heat treatment was determined to be less than about 925.

These comparisons show the surprising effect of using lead tungstate as a stabilizer, ie the resulting Knoop hardness is 1385-2200 after heat treatment and 950-1050 before heat treatment, and the coating is continuous without any spots.

Varying the concentration of lead tungstate in the bath gave the following results. In terms of grams of lead tungstate in the bath: at 0.0025 grams, the bath was unstable; at 0.003 grams, a slight improvement was observed; at 0.008 grams, the deposition rate was uncontrollable and moderate after 10 minutes Drop-out; at 0.0104 g, the bath was unstable and seed out was severe; at 0.013 g, the bath was unstable and seed out was severe; at 0.0156 g, the bath was unstable and seed out Severe particle precipitation; at 0.0182 g, the bath was initially unstable but corrected itself in time; at 0.0208 g, the result was good; at 0.05 g, the result was excellent; at 0.065 g, the result was good but the deposition rate was slow; at 0.07 At 0.09 grams, the deposition rate was slower; at 0.1 grams, the deposition rate was slower at about 0.0004 mils/hour; at 0.2 grams, the deposition rate was slower at about 0.0003 mils/hour ; same at 0.3 g; at 0.4 g, plating stops.

At about 0.0104-0.014 g/gal lead tungstate, no non-uniform coating was observed. The coating covers the surface with spots. The structure of the coating is irregular. If the lead tungstate in the bath rises above about 0.0142, the coating becomes continuous and uniform. The spots disappear.

These results indicate that the concentration of lead tungstate in the bath can be about 0.0142-0.30 grams per gallon of plating bath. A preferred concentration range is about 0.0128-0.2 grams.

From the foregoing description, the best proportions, process steps, and compositions of the present invention, including variations in size, material, shape, form, function and manner of operation, assembly and application, will be apparent to those skilled in the art , so the invention is meant to include all equivalents of what is stated in the specification.

Accordingly, the foregoing is considered as illustrative only of the principles of the invention. Furthermore, since many modifications and changes will readily occur to those skilled in the art, it is not appropriate to limit the invention to the exact construction and operation shown and described, so any suitable modifications and equivalents may be employed within the scope of the invention .

The invention has been described thus far.

Claims (43)

1. goods with the amorphous coating of wear resistance, this coating comprises the nickel borides that is dispersed in nickel/boron alloy, and wherein nickel is 67.5-97.0% weight, and boron is 2.5-10% weight, and the Knoop hardness of this coating is greater than 1385, and wherein said coating is speckless continuously.

2. according to the goods of claim 1, wherein said abrasion resistant coatings comprises the nickel of 93-97% weight and the boron of 7-3% weight.

3. according to the goods of claim 2, the Knoop hardness of wherein said abrasion resistant coatings is at least about 1400-2200.

4. according to the goods of claim 1, the thickness of wherein said abrasion resistant coatings is about 0.001-0.04 inch.

5. according to the goods of claim 1, wherein use the cobalt replacement nickel to the highest about 50% nickel.

6. one kind is used for providing on base material hard, wear resistance and coating erosion resistance, flexible coating to bathe, and the pH value that described coating is bathed is about 10-14 and comprises:

(1) nickel ion of about 0.175-2.10 mole/gallon coating bath,

(2) plumbous tungstate of significant quantity to be stablizing this coating and bathe and to form a kind of be speckless continuous coated, and plumbous tungstate can not have any remarkable deposition in described coating;

(3) the metal ion Synergist S-421 95 of significant quantity presents in an amount at least sufficient to suppress described metal ion and bathes precipitation by coating:

(4) the borohydride reductive agent of significant quantity; With

(5) optionally, the highest 1.05 moles/gallon cobalt.

7. bathe according to the coating of claim 6, wherein said coating is bathed and is comprised the plumbous tungstate of about 0.0156-0.3 gram/gallon as stablizer.

8. bathe according to the coating of claim 6, wherein said metal ion Synergist S-421 95 is selected from water-soluble salt, quadrol, diethylenetriamine, diethylenetriamine, ethylenediamine tetraacetic acid (EDTA) and the ammonia of tartrate, citric acid, oxalic acid.

9. coating is according to Claim 8 bathed, and wherein said metal ion Synergist S-421 95 is a quadrol.

10. bathe according to the coating of claim 7, wherein said borohydride reductive agent is selected from sodium borohydride, potassium borohydrid, trimethoxy sodium borohydride and trimethoxy potassium borohydrid.

11. the coating according to claim 10 is bathed, wherein said borohydride reductive agent is a sodium borohydride.

12. bathe according to the coating of claim 10, wherein said borohydride concentration is about 0.017-0.035 mole/as logical sequence.

13. the coating according to claim 6 is bathed, the concentration of wherein said metal ion Synergist S-421 95 is that about 2.26-6.795 mole/gallon coating is bathed.

14. the coating according to claim 7 is bathed, wherein said nickel ion concentration is about 0.35-1.57 mole/gallon.

15. the coating according to claim 6 is bathed, wherein said plumbous tungstate ionic concn is about 0.0182-0.25 gram/gallon.

16. the metal coating composition that will comprise nickel and boron deposits to the method on the base material, this method comprises:

A kind of plating bath according to claim 6 is provided;

Described base material to be coated is immersed in the described bath; Then

This coatings chemistry is deposited on this base material.

17. according to the method for claim 16, the pH value of wherein said bath before coating is adjusted to about 12-14.

18. according to the method for claim 16, wherein said metal ion Synergist S-421 95 comprises a kind of compound that is selected from quadrol, tartaric water-soluble salt and ammonia.

19. according to the method for claim 18, wherein said metal ion Synergist S-421 95 is a quadrol.

20. according to the method for claim 16, wherein said borohydride reductive agent is selected from sodium borohydride, potassium borohydrid, trimethoxy sodium borohydride and trimethoxy potassium borohydrid.

21. according to the method for claim 20, wherein said borohydride reductive agent is basic sodium borohydride.

22. according to the method for claim 16, wherein with described metallic coating thermal treatment.

23. the thickness of making by the method for claim 16 under the situation of getting rid of heat treatment step surpasses 0.00028 inch product, wherein said coating is made up of nickel and boron basically.

24. the thickness of making by the method for claim 22 surpasses about 0.0001 inch product.

25. the thickness of making by the method for claim 23 is the product of about 0.001-0.04 inch.

26. the Knoop hardness of making by the method for claim 22 is at least 1375 product.

27. the Knoop hardness of making by the method for claim 26 is the product of about 1400-2200.

28. the Knoop hardness of making by the method for claim 23 is greater than 950 to about 1050 product.

29. a pH value is greater than 8 enriched material, the quadrol that wherein comprises the plumbous tungstate of about 2-31 gram/gallon, about 100-700 milliliter is as metal ion Synergist S-421 95 and pH value conditioning agent.

30., wherein comprise the quadrol of 300-400 milliliter according to the enriched material of claim 29.

31. a pH value is about 10.5 enriched material, wherein comprises the quadrol and the pH value conditioning agent of the plumbous tungstate of about 7-12 gram/gallon, about 300-400 milliliter.

32. one kind is used for providing on base material hard, wear resistance and coating erosion resistance, flexible coating to bathe, the pH value that described coating is bathed is about 12-14 and comprises:

(1) nickel ion of about 0.35-1.57 mole/gallon coating bath,

(2) plumbous tungstate of about 0.0208-0.08 gram/gallon is as stablizer;

(3) the metal ion Synergist S-421 95 of about 3.3-3.8 mole/gallon is bathed precipitation to suppress described metal ion from coating;

(4) the borohydride reductive agent of about 0.045-0.08 mole/gallon; With

(5) dispensable cobalt.

33. goods with the amorphous coating of wear resistance, wherein said coating comprises the nickel of 67.5-97% weight, the boron of 2.5-10% weight, the thickness of described coating surpasses 0.0003 inch and Knoop hardness at least about 950-1050, and wherein said coating is not heat-treated and described coating continuously and immaculate.

34. according to the goods of claim 33, wherein said abrasion resistant coatings comprises the nickel of 93-97% weight and the boron of 3-7% weight.

35. according to the goods of claim 34, the thickness of wherein said abrasion resistant coatings is about 0.001-0.04 inch.

36. according to the goods of claim 34, wherein the cobalt replacement nickel is to the highest about 50% nickel.

37. bathe according to the coating that claim 6 is produced, wherein said bath is made by composition (1), (2), (3), (4) and dispensable (5) are mixed.

38. according to the goods of claim 4, the thickness of wherein said coating is above 0.00025 inch.

39. according to the goods of claim 4, wherein said goods are metal.

40. goods with the amorphous coating of continuous wear resistance that is speckless, described coating is made up of the nickel borides that is dispersed in nickel/boron alloy basically, wherein nickel is 67.5-97% weight, and boron is 2.5-10% weight, and the Knoop hardness of described coating is greater than about 1385.

41. goods with the amorphous coating of continuous wear resistance that is speckless, wherein said coating is basically by the nickel of 67.5-97% weight, the boron of 0.5-10% weight is formed, the thickness of described coating surpasses 0.0003 inch and Knoop hardness at least about 950-1050, and wherein said coating is not heat-treated.

42. the thickness of producing according to the method for claim 16 under the situation of getting rid of heat treatment step surpasses 0.00028 inch product, wherein lead or the tungstate concentration limit in this coating is at trace.

43. according to the product that the method for claim 21 is produced, wherein lead or the tungstate concentration limit in this coating is at trace.