MXPA98003388A - Article recubie - Google Patents

Abstract

An article is described which is coated with a multilayer coating comprising a layer of nickel deposited on the surface of the article, a layer of nickel-tungsten-boron deposited on the nickel layer, a layer of refractory metal, preferably zirconium, deposited on the nickel-tungsten-boron layer, a sandwich layer comprising alternating layers of a refractory metal and a refractory metal composite deposited on the refractory metal layer, a layer of a refractory metal compound, preferably nitride of zirconium, deposited on the sandwich layer and a layer consisting of refractory metal oxide or the reaction products of a refractory metal, oxygen and nitrogen, deposited on the layer of the refractory metal composite

Description

COATED ARTICLE FIELD OF THE INVENTION This invention relates to substrates, in particular brass substrates, coated with a decorative and protective coating in multilayers.

BACKGROUND OF THE INVENTION It is currently the practice with various brass articles such as lamps, tripods, candlesticks, door knobs, locks, door plates and the like, to smooth and polish the surface of the article first to a high gloss and then apply a organic protective coating, such as one comprising acrylics, urethanes, epoxies and the like on this polished surface. While this system is generally quite satisfactory, it has the disadvantage that the smoothing and polishing operation, particularly if the article is of a complex shape, is labor intensive. Also, known organic coatings are not always as durable as desired, particularly in outdoor applications where the articles are exposed to the elements and ultraviolet radiation. It would therefore be quite advantageous if the articles of brass or even other metal articles could be provided with a coating which gives the article the appearance of highly polished brass and also provides wear resistance and protection against corrosion. The present invention provides such a coating.

BRIEF DESCRIPTION OF THE INVENTION The present invention is directed to a metal substrate having a multilayer coating disposed or deposited on its surface. More particularly, it is directed to a metallic substrate, in particular brass, which has deposited on its surface multiple overlapping metallic layers of certain specific types of metals or metal compounds. The coating is decorative and also provides resistance to corrosion and wear. The coating provides the appearance of highly polished brass, that is, it has a brass color tone. Thus, the surface of an article that has the coating on it simulates the surface of highly polished brass. A first layer deposited directly on the surface of the substrate consists of nickel. The first layer may be monolithic or may consist of two different nickel layers such as a semi-gloss nickel layer deposited directly on the surface of the substrate and a bright nickel layer superimposed on the semi-gloss nickel layer. Arranged on the nickel layer is a layer consisting of a nickel-tungsten-boron alloy. On the nickel-tungsten-boron alloy layer there is a layer consisting of a non-precious refractory metal such as zirconium, titanium, hafnium or tantalum, preferably zirconium or titanium. On the refractory metal layer there is a sandwich layer consisting of a plurality of alternating layers of a non-precious refractory metal, preferably zirconium or titanium, and a non-precious refractory metal compound, such as a zirconium compound, of titanium, composed of hafnium or tantalum compound, preferably a zirconium compound or a titanium compound such as zirconium nitride or titanium nitride. On the sandwich layer is a layer comprising a non-precious refractory metal compound such as a zirconium compound or titanium compound, such as zirconium nitride or titanium nitride. In one embodiment, a layer consisting of the reaction products of a non-precious refractory metal, preferably zirconium or titanium, oxygen and nitrogen is disposed on the non-precious refractory metal compound layer. The nickel-nickel-tungsten-boron alloy layers are generally applied by electrodeposition. The layers of non-precious refractory metal, the refractory metal compound and the reaction products of refractory metal, oxygen and nitrogen are generally applied by vapor deposition processes such as electron deposition (or sputtering).

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is a cross-sectional view of a portion of the substrate having a multilayer coating mode deposited on its surface.

DESCRIPTION OF THE PREFERRED MODALITY The substrate 12 may be any metal or metal alloy such as copper, steel, brass, tungsten, nickel alloys and the like. In a preferred embodiment, the substrate is made of brass. The nickel layer 13 is deposited on the surface of the substrate 12 by conventional and well-known electrodeposition processes.

These processes include the use of a conventional electrodeposition bath such as, for example, a Watts bath as the electrodeposition solution. Typically, such baths contain nickel sulfate, nickel chloride and boric acid dissolved in water. All electrodeposition solutions of chloride, sulfamate and fluoroborate can be used. These baths may optionally include a variety of well-known and conventionally used compounds, such as release agents, brighteners and the like. To produce a specularly bright nickel layer, at least one class I polish and at least one class II polish is added to the electrodeposition solution. Class I brighteners are organic compounds which contain sulfur. Class II polishes are organic compounds which do not contain sulfur.

Class II brighteners can also cause release and when added to the electrodeposition bath without the sulfur-containing class I brighteners, semi-glossy nickel deposits result. These class I brighteners include alkylnaphthalene- and benzenesulfonic acids, benzene and naphthalene-di-and trisulphonic acids, benzenes and naphthalenesulphonamides and sulfonamides such as saccharin, vinyl and allylsulfonamides and sulphonic acids. Class II polishes are generally unsaturated organic materials such as, for example, acetylenic or ethylenic alcohols, ethoxylated and propoxylated acetylenic alcohols, coumarins and aldehydes. These Class I and Class II brighteners are well known to those skilled in the art and are commercially available. They are described, inter alia, in U.S. Patent No. 4,421,611 incorporated herein by reference. The nickel layer may be a monolithic layer consisting of, for example, semi-bright nickel, bright nickel, or may be a double layer containing a layer comprising semi-gloss nickel and a layer comprising bright nickel. The thickness of the nickel layer is generally in the range of about 2.54 microns (0.000100 inches), preferably about 3.81 microns (0.000150 inches) to about 88. 9 microns (0.0035 inches). As is well known in the art, before the nickel layer is deposited on the substrate, the substrate is subjected to activation upon being placed in a conventional and well-known acid bath. In a preferred embodiment as the Figure is illustrated, the nickel layer 13 actually consists of two different nickel layers 14 and 16. The layer 14 consists of semi-gloss nickel while the layer 16 consists of bright nickel. That double nickel deposit provides improved corrosion protection to the underlying substrate. The semi-bright sulfur-free plate 14 is deposited by conventional electrodeposition processes, directly on the surface of the substrate 12. The substrate 12 containing the semi-gloss nickel layer 14 is then placed in a bright nickel electrodeposition bath and the layer 16 of bright nickel is deposited on the semi-gloss nickel layer 14. The thickness of the semi-gloss nickel layer and the bright nickel layer is effective thickness to provide improved corrosion protection. In general, the thickness of the semi-gloss nickel layer is at least about 1.27 microns (0.00005 inches), preferably at least about 2.54 microns (0.0001 inches) and more preferably at least about 3.81 microns (0.00015 inches). The upper thickness limit is not generally critical and is determined by secondary considerations such as cost. In general, however, a thickness of about 38.1 microns (0.0015 inches), preferably about 25.4 microns (0.001 inches) and more preferably about 19.0 microns (0.00075 inches) should not be exceeded. The bright nickel layer 16 generally has a thickness of at least about 1.27 microns (0.00005 inches), preferably at least about 3.175 microns (0.000125 inches) and more preferably at least about 6.35 microns (0.00025 inches). The range of the upper thickness of the bright nickel layer is not critical and is generally controlled by considerations such as cost. In general, however, a thickness of approximately 63. 5 microns (0.0025 inches), preferably about 50.8 microns (0.002 inches) and more preferably about 38.1 microns (0.0015 inches) should not be exceeded. The bright nickel layer 16 also functions as a release layer which tends to cover or fill imperfections in the substrate. Arranged on the bright nickel layer 16 is a layer 20 comprising a nickel-tungsten-boron alloy. More specifically, layer 20 consists of an alloy of substantially amorphous nickel, tungsten and boron compound, more specifically an amorphous nickel, tungsten and boron composite alloy. The layer 20 is deposited on the layer 16 by conventional electrodeposition processes. The electrodeposition bath is operated at a temperature of about 46 ° C to 52 ° C (115 ° F to 125 ° F) and at a preferred pH range of about 8.2 to about 8.6. Soluble, preferably water-soluble, well-known salts of nickel, tungsten and boron are used in the bath or electrodeposition solution to provide concentrations of nickel, tungsten and boron. The layer 20 of nickel-tungsten-boron alloy serves, i n t i a l, to reduce the galvanic couple between the refractory metal such as layers 22 and 24 containing zirconium, titanium, hafnium or tantalum and the nickel layer. The nickel-tungsten-boron alloy layer generally consists of from about 50 to about 70 weight percent nickel, about 30 to 50 weight percent tungsten and from about 0.05 to about 2.5 weight percent of boron, preferably from about 55 to about 65 weight percent nickel, about 35 to about 45 weight percent tungsten and from about 0.5 to about 2.0 weight percent boron and more preferably from about 57.5 to about 62.5 weight percent nickel, about 37.5 to about 42.5 weight percent tungsten and from about 0.75 to about 1.25 weight percent boron. The electrodeposition bath contains sufficient amounts of the soluble salts of nickel, tungsten and boron to provide a nickel-tungsten-boron alloy of the composition described above. A nickel-tungsten-boron electroplating bath effective to provide a nickel-tungsten-boron alloy of which a composition is commercially available, such as the Amplate ™ system from Amorphous Technologies International of Laguna Niguel, California. A typical nickel-tungsten-boron alloy containing about 59.5 weight percent nickel, about 39.5 weight percent tungsten and about 1% boron. The nickel-tungsten-boron alloy is an amorphous / nanocrystalline composite alloy. Such an alloy layer is deposited by the AMPLATE electrodeposition process marketed by Amorphous Technologies International. The thickness of the layer 20 of nickel-tungsten-boron alloy is of a thickness which is at least effective to reduce the galvanic coupling between the hafnium, tantalum, zirconium or titanium, preferably zirconium or titanium and more preferably layers containing zirconium 22 and 24 and nickel layer 16. In general, this thickness is at least about 0.508 microns (0.00002 inches), preferably at least about 1.27 microns (0.00005 inches) and more preferably at least approximately 2.54 microns (0.0001 inches). The range of the upper thickness is not critical and is generally dependent on economic considerations. In general, a thickness of about 63.5 microns (0.0025 inches), preferably about 50.8 microns (0.002 inches) and more preferably about 25.4 microns (0.001 inches), should not be exceeded. Arranged on layer 20 of nickel-tungsten-boron alloy, there is a layer 22 consisting of a non-precious refractory metal., such as hafnium, tantalum, zirconium or titanium, preferably zirconium or titanium and more preferably zirconium. The layer 22 is deposited on the layer 20 by conventional and well-known techniques, such as vacuum coating, physical vapor deposition, such as by electronic deposition (or sputter metallization) and the like. The techniques and equipment of ionic electronic deposition (or sputter metallization) are described, inter alia, in T. Van Vorous, "Planar Magnetron Sputtering; A New Industrial Coating Technique ", Solid State Technology, December 1976, pages 62-66; OR.

Kapacz and S. Schulz, "Industrial Application of Decorative Coatings - Principle and Advantages of the Sputter Ion Plating Process ", Soc. Vac. Coat., Proc. 34th Arn. Techn. Conf., Philadelphia, United States United, 1991, 48-61; and the North American Patents Nos. 4,162,954 and 4,591,418, all of which are incorporated herein by reference. Briefly, in the electronic deposition process (or sputter metallization), the refractory metal such as the titanium or zirconium target, which is the cathode, and the substrate are placed in a vacuum chamber. The air in the chamber is evacuated to produce vacuum conditions in the chamber. An inert gas, such as Argon, is introduced into the chamber. The gas particles are ionized and accelerated to the target to dislodge the titanium or zirconium atoms. Then the target material is dislodged, they are normally deposited as a coating film on the substrate. The layer 22 has a thickness which is generally at least about 0.00635 microns (0.00000025 inches), preferably at least about 0.0127 microns (0.0000005 inches) and more preferably at least about 0.0254 microns (0.000001 inches). The range of the upper thickness is not critical and is generally dependent on considerations such as cost. In general, however, layer 22 should not be thicker than about 1.27 microns (0.00005 inches), preferably about 0.381 microns (0.000015 inches) and more preferably about 0.254 microns (0.000010 inches). In a preferred embodiment of the present invention, the layer 22 consists of titanium or zirconium, preferably zirconium and is deposited by ionic electronic deposition (or sputter metallization). Disposed on layer 22 is a sandwich layer 26 comprising alternating layers 28 and 30 of a non-precious refractory metal composite and a non-precious refractory metal. Layer 26 generally has a thickness of about 1.27 microns (0.00005 inches) to about 0.0254 microns (0.000001 inches), preferably about 1.016 microns (0.00004 inches) to about 0.0508 microns (0.000002 inches) and more preferably about 0.762 microns (0.000030 inches) to approximately 0.0762 microns (0.000003 inches). The non-precious refractory metal compounds comprising the layers 28 include a hafnium compound, a tantalum compound, a titanium compound or a zirconium compound, preferably a titanium compound or a zirconium compound and more preferably a compound of zirconium. These compounds are selected from nitrides, carbides and carbonitrides, nitrides are preferred. Thus, the titanium compound is selected from titanium nitride, titanium carbide and titanium carbonitride, titanium nitride is preferred. Zirconium carbide and zirconium carbonitride, zirconium nitride is preferred. The nitride compounds are deposited by any of the well known and conventional reactive vacuum deposition processes, in which reactive ionic deposition (or metalization by bombardment) is included. The electronic deposition (or ion sputtering) reactive is similar in general to ionic electronic deposition, except that a gaseous material which reacts with the target evicted material is introduced into the chamber. Thus, in the case where the zirconium nitride comprises the layers 28, the objective consists of zirconium and the nitrogen gas is the gaseous material introduced into the chamber. The layers 28 generally have a thickness of at least about 0.000508 microns (0.00000002 inches), preferably at least about 0.00254 microns (0.0000001 inches) and more preferably at least about 0.0127 microns (0.0000005 inches). In general, the layers 28 should not be thicker than about 0.635 microns (0.000025 inches), preferably about 0.254 microns (0.00001 inches) and more preferably about 0.127 microns (0.000005 inches). The alternating layers 30 in the sandwich layer 26 with the layers 28 of the non-precious refractory metal composite consist of a non-precious refractory metal as described for the layer 22. The preferred metals comprising the layers 30 are titanium and zirconium. The layers 30 are deposited by any of the conventional and well-known vapor deposition processes, such as ionic electronic deposition (or sputtering) or electrodeposition processes. The layers 30 have a thickness of at least about 0.000508 microns (0.00000002 inches), preferably at least about 0.00254 microns (0.0000001 inches) and more preferably at least about 0.0127 microns (0.0000005 inches). In general, the layers 30 should not be thicker than about 0.635 microns (0.000025 inches), more preferably about 0.254 microns (0.00001 inches) and more preferably about 0.127 microns (0.000005 inches). The number of alternating layers of metal 30 and metal nitride 28 in sandwich layer 26 is generally an effective amount to reduce stress and improve chemical resistance. In general this amount is from about 50 to about two alternating layers 28, 30, preferably from about 40 to about four layers 28, 30 and more preferably from about 30 to about six layers 28, 30. The sandwich layer 26 that comprises multiple alternating layers 28 and 30 generally serves, inter alia, to reduce the film tension, increase the overall hardness of the film, improve the chemical resistance and realign the crosslink to reduce pores and the grain boundaries that are They extend through the entire movie. A preferred method for the formation of the sandwich layer 26 is by the use of electronic deposition (or sputtering) to deposit a layer 30 of a non-precious refractory metal such as zirconium or titanium followed by reactive electronic deposition (or metallization). by reactive sputtering) to deposit a layer 28 of non-precious refractory metal nitride, such as zirconium nitride or titanium nitride. Preferably, the flow velocity of the nitrogen gas is varied (pulsed) during electronic deposition (or sputtering) between zero (no nitrogen gas is introduced) at the introduction of nitrogen to a desired value to form multiple alternating layers of metal 28, 30 and metal nitride 28 in the sandwich layer 26. The thickness ratio of the layers 30 to 28 is at least about 20/80, preferably about 30/70 and more preferably approximately 40/60. In general, it should not be greater than about 80/20, preferably about 70/30 and more preferably about 60/40. Arranged on the sandwich layer 26 is a layer 32 comprising a non-precious refractory metal compound, preferably a non-precious refractory metal nitride, carbonitride or carbide and more preferably a nitride. The layer 32 consists of a hafnium compound, a tantalum compound, a titanium compound or a zirconium compound, preferably a titanium compound or a zirconium compound and more preferably a zirconium compound. The titanium compound is selected from titanium nitride, titanium carbide and titanium carbonitride, titanium nitride is preferred. The zirconium compound is selected from zirconium nitride, zirconium carbonitride and zirconium carbide, zirconium nitride is preferred. The layer 32 provides resistance to wear and abrasion and the desired color or appearance, such as, for example, polished brass. The layer 32 is deposited on the layer 26 by means of conventional and well-known electronic deposition or deposition processes, such as vacuum coating, reactive electronic deposition (or reactive sputtering metallization) and the like. The preferred method is reactive electronic deposition (or sputtering). The layer 32 has a thickness at least effective to provide resistance to abrasion. In general, this thickness is at least 0.0508 microns (0.000002 inches), preferably at least 0.1016 microns (0.000004 inches) and more preferably at least 0.1524 microns (0.000006 inches). The upper range of thickness is not generally critical and is dependent on considerations such as cost. In general, it should not exceed a thickness of approximately 0.762 microns (0.00003 inches), preferably approximately 0. 0635 microns (0.000025 inches) and more preferably approximately 0.508 microns (0.000020 inches). Zirconium nitride is the preferred coating material since it more closely provides the appearance of polished brass. By controlling the amount of nitrogen gas introduced into the reaction vessel during reactive electronic deposition (or sputtering), the color of the zirconium nitride can be made similar to that of various shades of brass. In one embodiment of the invention, a layer 34 comprising the reaction products of a non-precious refractory metal, an oxygen-containing gas such as oxygen and nitrogen is deposited on the layer 32. The refractory metals that can be employed in the practice of this invention are those in which they are capable of forming a metal oxide, metal nitride and metal oxy-nitride under appropriate conditions, for example, reaction with gases such as oxygen and nitrogen. The metals may include tantalum, hafnium, zirconium and titanium, preferably titanium and zirconium and more preferably zirconium. The reaction products of the metal, the oxygen-containing gas such as oxygen and nitrogen generally consist of the metal oxide, metal nitride and metal oxy-nitride. Thus, for example, the reaction products of zirconium, oxygen and nitrogen comprise zirconium oxide, zirconium nitride and zirconium oxynitride. The layer 34 can be deposited by a well-known and conventional deposition technique, in which the electronic deposition (or sputtering) of a pure metal target or a target composed of oxides, nitrides and / or metals is included, reactive evaporation, ionic ion-assisted deposition, molecular beam epitaxy, chemical vapor deposition and deposition of organic precursors in the form of liquids. Preferably, however, the metal reaction products of this invention are deposited by reactive ion electrode deposition. These metal oxides and metal nitrides including zirconium oxide and zirconium nitride alloys and their preparation and deposition are conventional and well known and are described, inter alia, in U.S. Patent No. 5,367,285, the description of which is incorporated herein by reference. In another embodiment, instead of the layer 34 consisting of the reaction products of a refractory metal, oxygen and nitrogen, it consists of a non-precious refractory metal oxide. The refractory metal oxides of which the layer 34 is comprised include, but are not limited to, hafnium oxide, tantalum oxide, zirconium oxide and titanium oxide, preferably titanium oxide and zirconium oxide and more preferably zirconium oxide. These oxides and their preparation are conventional and well known. The layer 34 containing reaction products of metal, oxygen and nitrogen or metal oxide generally has a thickness of at least effective to provide improved chemical resistance. In general, this thickness is at least about 0.00127 microns (0.00000005 inches), preferably at least about 0.00254 microns (0.0000001 inches) and more preferably at least about 0.00381 microns (0.00000015 inches). In general, the metal oxynitride layer should not be thicker than about 0.127 microns (0.000005 inches), preferably about 0.0508 microns (0.000002 inches) and more preferably about 0.0254 microns (0.000001 inches). In order for the invention to be understood more easily, the following example is provided. The example is illustrative and does not limit the invention to it. EXAMPLE 1 Brass door plates are placed in a conventional rinsing cleaner bath containing standard and well known soaps, detergents, deflocculants and the like, which is maintained at a pH of 8.9 - 9.2 and at a temperature of 82 ° C - 93 ° C (180-200 ° F) for 30 minutes. Then the brass plates are placed for 6 minutes in a conventional ultrasonic alkaline cleaner bath. The ultrasonic cleaning bath has a pH of 8.9 -9.2, is maintained at a temperature of about 71 ° C - 82 ° C (160-180 ° F) and contains conventional and well-known soaps, detergents, deflocculants and the like. After the ultrasonic cleaning, the sheets are rinsed and placed in a conventional alkaline electrolysis bath for approximately 2 minutes. The electro-cleaning bath contains an insoluble submerged steel anode, it is maintained at a temperature of about 60-82 ° C (140-180 ° F), a pH of about 10.5 - 11.5 and contains standard and conventional detergents. The sheets are then rinsed twice and placed in a conventional acid activator bath for about one minute. The acid activator bath has a pH of about 2.0-3.0, is at an ambient temperature and contains an acid salt based on sodium fluoride. The sheets are then rinsed twice and placed in a semi-bright nickel electroplating bath for about 10 minutes. The semi-gloss nickel bath is a conventional and well-known bath having a pH of about 4.2-4.6, maintained at a temperature of about 54-65 ° C (130-150 ° F), contains NiS04, NiCl2, boric acid and brighteners. A layer of semi-gloss nickel of an average thickness of approximately 6.35 microns (0.00025 inches) is deposited on the surface of the sheet. The sheets containing the semi-gloss nickel layer are then rinsed twice and placed in a bright nickel electrodeposition bath for approximately 24 minutes. The bright nickel bath is generally a conventional bath which is maintained at a temperature of about 54-65 ° C (130-150 ° F), a pH of about 4.0-4.8, contains NiS0, NiCl2, boric acid and brightener -dores A bright nickel layer with an average thickness of approximately 19. 0 microns (0.00075 inches) is deposited on the semi-gloss nickel layer. The glossy, semi-gloss nickel-coated sheets are rinsed three times and placed for approximately 40 minutes in a nickel-tungsten-boron electrodeposition bath available from Amorphous Technologies International of California as the AMPLATE bath. The bath uses an insoluble platinum titanium anode, maintained at a temperature of about 46-52 ° C (115-125 ° F) and a pH of about 8.2-8.6. A layer of nickel-tungsten-boron of an average thickness of approximately 10.16 microns (0.0004 inches) is deposited on the bright nickel layer. Then the sheets coated with nickel-tungsten-boron are rinsed twice. Electrodeposited nickel-tungsten-boron alloy plates are placed in an electrodeposition vessel by sputtering. This container is a stainless steel vacuum vessel marketed by Leybold A. G. of Germany. The container is a generally cylindrical container containing a vacuum chamber which is adapted to be evacuated by means of pumps.

A source of argon gas is connected to the chamber by an adjustable valve to vary the flow rate of argon to the chamber. In addition, two sources of nitrogen gas are connected to the chamber through an adjustable valve to vary the flow velocity of nitrogen gas to the chamber. Two pairs of Magnetron-type target assemblies or mounts are mounted in a separate spaced relationship in the chamber and connected to the negative outputs of variable direct current power supplies. The targets constitute the cathodes and the wall of the chamber is the common anode for the target cathodes. The objective material consists of zirconium. A substrate carrier is provided, which carries the substrates, that is, the sheets, for example, can be suspended from the top of the chamber and rotated by a variable speed motor to carry the substrates between each pair of sets or magnetron objective assemblies. The carrier is conductive and electrically connected to the negative output of a variable direct current power source. The coated or electrodeposited sheets are mounted on the carrier of the substrate in the electrodeposition vessel by sputtering. The vacuum chamber is evacuated to a pressure of approximately 5 x 10"mbar and heated to a temperature of approximately 400 ° C via a radiant electric heating element.The target material is cleaned by sputtering to remove contaminants from its surface. The sputter cleanup is carried out for approximately half a minute by applying enough energy to the cathodes to obtain a current flow of approximately 18 amps and the introduction of argon gas at the rate of approximately 200 standard cubic centimeters per A pressure of approximately 3x10"3 millibars is maintained during the sputter cleanup. Then the sheets are cleaned by a process of acid attack at low pressure. The acid attack process at low pressure is carried out for about 5 minutes and involves the application of a negative direct current potential which is increased over a period of one minute from about 1200 to about 1400 volts to the plates and the application of direct current energy to the cathodes to obtain a current flow of approximately 3.6 amperes.

Argon gas is introduced at a rate which is increased over a period of one minute from about 800 to about 1000 standard cubic centimeters per minute and the pressure is maintained at a pressure of about 1 × 10 L-2 mbar. The plates are rotated between the Magnetron target assemblies or assemblies at a rate of one revolution per minute. The sheets are then subjected to a cleaning process by acid attack at high pressure for approximately 15 minutes. In the high-pressure acid attack process, argon gas is introduced into the vacuum chamber at a rate which is increased over a period of 10 minutes from about 500 to 650 standard cubic centimeters per minute (this is, at the beginning, the flow rate is 500 standard cubic centimeters per minute and after ten minutes, the flow rate is 650 standard cubic centimeters per minute and persists at 650 standard cubic centimeters per minute for the rest of the attack process by high pressure acid), the pressure is maintained at a pressure of approximately 2xl0_1 millibars and a negative potential which is increased over a period of ten minutes from approximately 1400 to 2000 volts is applied to the sheets. The plates are rotated between the Magnetron target assemblies or assemblies at a rate of about one revolution per minute. The pressure in the container is maintained at a pressure of approximately 2xl0_1 millibars. The sheets are then subjected to another cleaning process by acid attack at low pressure for approximately five minutes. During this cleaning process by acid attack at low pressure, a negative potential of approximately 1400 volts is applied to the sheets, direct current energy is applied to the cathodes to obtain a current flow of approximately 2.6 amperes and argon gas is introduced to the vacuum chamber at a speed which is increased over a period of five minutes from about 800 standard cubic centimeters per minute to about 1000 standard cubic centimeters per minute. The pressure is maintained at a pressure of approximately 1.1x10"'millibars and the plates are rotated at a rate of about one revolution per minute (rpm) .The target material is again cleaned by sputtering for about one minute by the application of energy at the cathodes, sufficient to obtain a current flow of approximately 18 amperes, the introduction of argon gas at a rate of approximately 150 standard cubic centimeters per minute and maintained at a pressure of approximately 3x10 ~ 3 mbar. the cleaning process, shields are interposed between the sheets and the magnetron target assemblies or assemblies to prevent the deposition of the target material on the sheets The shields are removed and a layer of zirconium having an average thickness of approximately 0.0762 microns (0.000003 inches) is deposited on the nickel / tungsten / boron layer of the sheets for a period of Inco minutes This deposition process by means of sputtering comprises the application of direct current energy to the cathodes, to obtain a current flow of approximately 18 amperes, the introduction of argon gas to the vessel at a rate of approximately 450 standard cubic centimeters per minute, the pressure is maintained in the vessel at a pressure of about 6x10"3 millibars and the plates are rotated at a speed of about 0.7 revolutions per minute. After the zirconium layer is deposited, the sandwich layer of alternating layers of zirconium nitride and zirconium is deposited on the zirconium layer. The argon gas is introduced into the vacuum chamber at a rate of approximately 250 standard cubic centimeters per minute. Direct current power is supplied to the cathodes to obtain a current flow of approximately 18 amps. A polarization voltage of approximately 200 volts is applied to the substrates. The nitrogen gas is introduced at an initial velocity of approximately 80 standard cubic centimeters per minute. Then the nitrogen flow is reduced to zero or almost zero. This pulsation of nitrogen is adjusted in such a way that it is present at approximately a 50% duty cycle. The pulsation continues for approximately 10 minutes to result in a sandwich stack with approximately six layers of an average thickness of approximately 0.0254 microns (0.000001 inches) each. The sandwich stack has an average thickness of approximately 0.1524 microns (0.000006 inches). After the sandwich layer of alternating layers of zirconium nitride and zirconium is deposited, a layer of zirconium nitride, which has an average thickness of approximately 0.254 microns (0.00001 inches) is deposited in the sandwich stack for a period of approximately 20 minutes. In this stage, nitrogen is regulated to maintain a partial ionic current of approximately 6.3 x 10-11 amperes. The argon, direct current energy and polarization voltage are maintained as indicated above. After the completion of the deposition of the zirconium nitride layer, a thin layer of the reaction products of zirconium, oxygen and nitrogen is deposited, which has an average thickness of about 0.00635 microns (0.00000025 inches) over a period of about 30 seconds. At this stage, the introduction of argon is maintained at a rate of approximately 250 standard cubic centimeters per minute, the cathode current is maintained at approximately 18 amps, the bias voltage is maintained at approximately 200 volts and the nitrogen flow is adjusted at a speed of approximately 80 standard cubic centimeters per minute. Oxygen is introduced at a rate of approximately 20 standard cubic centimeters per minute. While certain embodiments of the invention have been described for purposes of illustration, it will be understood that there may be many modifications and embodiments within the general scope of the invention. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers. Having described the invention as above, property is claimed as contained in the following:

Claims (35)

1. CLAIMS 1. An article comprising a substrate that has a multilayer coating arranged on at least a portion of its surface, characterized in that it comprises: a layer consisting of semi-gloss nickel; a layer consisting of bright nickel; a layer consisting of a substantially amorphous nickel-tungsten boron alloy; a layer consisting of zirconium or titanium; a sandwich layer consisting of a plurality of alternating layers consisting of zirconium or titanium and of a zirconium compound or a titanium compound; and a layer consisting of a zirconium compound or a titanium compound. The article according to claim 1, characterized in that the layers consisting of zirconium or titanium consist of zirconium. 3. The article according to claim 2, characterized in that the layers consisting of a zirconium compound or a titanium compound consist of a zirconium compound. 4. The article according to claim 3, characterized in that the zirconium compound consists of zirconium nitride. 5. The article according to claim 1, characterized in that the substrate consists of brass. An article comprising a substrate having on at least a portion of its surface a multilayer coating, characterized in that it comprises: a layer consisting of semi-gloss nickel; a layer consisting of bright nickel; a layer consisting of a substantially amorphous nickel-tungsten boron alloy; a layer consisting of zirconium or titanium; a sandwich layer consisting of a plurality of alternating layers consisting of titanium or zirconium and of a zirconium compound or a titanium compound; a layer consisting of a zirconium compound or a titanium compound; and a layer consisting of zirconium oxide or titanium oxide. The article according to claim 6, characterized in that the layers consisting of zirconium or titanium consist of zirconium. The article according to claim 7, characterized in that the layers consisting of a zirconium compound or a titanium compound consist of a zirconium compound. 9. The article according to claim 8, characterized in that the zirconium compound is zirconium nitride. 10. The article according to claim 9, characterized in that the substrate is made of brass. 11. The article according to claim 6, characterized in that the substrate is made of brass. 12. An article comprising a substrate having on at least a portion of its surface a multilayer coating, characterized in that it comprises: a layer consisting of nickel; a layer consisting of a substantially amorphous nickel-tungsten boron alloy; a layer consisting of zirconium or titanium; a sandwich layer consisting of a plurality of alternating layers consisting of zirconium or titanium and of a zirconium compound or a titanium compound; and a layer consisting of a zirconium compound or a titanium compound. 13. The article according to claim 12, characterized in that the layer consisting of nickel consists of bright nickel. 14. The article according to claim 12, characterized in that the layers consisting of zirconium or titanium consist of zirconium. 15. The article according to claim 14, characterized in that the layers consisting of a zirconium compound or a titanium compound consist of a zirconium compound. 16. The article according to claim 15, characterized in that the zirconium compound consists of zirconium nitride. 17. The article according to claim 16, characterized in that the substrate consists of brass. 18. The article according to claim 12, characterized in that the substrate consists of brass. 19. An article comprising a substrate having on at least a portion of its surface a multilayer coating, characterized in that it comprises: a layer consisting of nickel; a layer consisting of a substantially amorphous nickel-tungsten-boron alloy; a layer consisting of zirconium or titanium; a sandwich layer consisting of a plurality of alternating layers consisting of titanium or zirconium and of a zirconium compound or a titanium compound; a layer consisting of a zirconium compound or a titanium compound; and a ca-jaa consisting of zirconium oxide or titanium oxide. 20. The article according to claim 19, characterized in that the f layer consists of bright nickel. 21. The article according to claim 20, characterized in that the layers consisting of zirconium or titanium consist of zirconium. 22. The article according to claim 21, characterized in that the layers consisting of a zirconium compound? A titanium eco-post are composed of a zirconium coapuesto. 23. The article according to claim 22, characterized in that the zirconium compound is zirconium nitride. 24. The article according to claim 19, characterized in that the layers consisting of zirconium or titanium consist of zirconium. 25. The article according to claim 24, characterized in that the layers consisting of a zirconium compound or a titanium compound consist of a zirconium compound. 26. The article according to claim 25, characterized in that the zirconium compound is zirconium nitride. 27. The article according to claim 26, characterized in that the substrate is made of brass. 28. The article according to claim 19, characterized in that the substrate is made of brass. 29. An article comprising a substrate having on a multilayer coating arranged on at least a portion of its surface, characterized in that it comprises: a layer consisting of semi-glossy nickel; a layer consisting of bright nickel; a layer consisting of a substantially amorphous nickel-tungsten-boron alloy; a layer consisting of zirconium or titanium; a sandwich layer consisting of a plurality of alternating layers consisting of zirconium or titanium and of a zirconium compound or a titanium compound; a layer consisting of a zirconium compound or a titanium compound; and a layer consisting of the reaction products of zirconium or titanium, a gas containing oxygen; and nitrogen. 30. The article according to claim 29, characterized in that the layers consisting of zirconium or titanium consist of zirconium. 31. The article according to claim 30, characterized in that the layers consisting of a zirconium compound or a titanium compound are composed of a zirconium compound. 32. The article according to claim 31, characterized in that the zirconium compound is zirconium nitride. 33. The article according to claim 32, characterized in that the layer consisting of the reaction products of zirconium or titanium, a gas containing oxygen and nitrogen, consists of the reaction products of zirconium, a gas containing oxygen and nitrogen. 34. The article according to claim 33, characterized in that the substrate is made of brass. 35. The article according to claim 29, characterized in that the substrate is made of brass.