RU2567428C1 - Protective-decorative coating of product and method for producing it (versions) - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: according to the first version, the method involves physical PVD vacuum deposition of an adhesion layer on a product, covering the adhesion layer with an inner layer and making an outer layer. The inner layer 1-5 mcm thick is made of titanium nitride or zirconium nitride by PVD deposition, whereas the outer layer 0.05-0.2 mcm thick is deposited by gold ion implantation with an ionic energy of 20-150 keV and a dose of more than 5·10¹⁷ ion/cm², the adhesive layer 0.2-0.3 mcm thick is made of a metal or its alloys being a part of the inner layer material. In the method according to the second version, the outer layer is made by deposition of a gold layer 0.05-0.2 mcm thick and ion mixing by exposure to gold ions with an ionic energy of 20-150 keV and a dose of more than 2·10¹⁷ ion/cm².

EFFECT: producing wear- and pushing-resistant biocompaticle coatings with good adhesion to the product.

13 cl, 3 dwg, 2 ex

Description

The invention relates to the field of protective and decorative coatings in a vacuum and can find application in the production of consumer goods, in particular in watch and jewelry production, in the manufacture of accessories, sanitary ware, as well as in instrumentation, including medicine.

Known wear-resistant protective and decorative coating of the product, which is a layer of a precious metal or its alloy, for example a layer of gold or its alloy, containing dispersed inclusions of a solid compound, for example titanium nitride, uniformly distributed throughout the volume of the layer; upon receipt of such a coating, these inclusions are coprecipitated in vacuum from the vapor phase together with a precious metal [Application No. 2589484 France, IPC С23С 16/30, 1987].

These coatings have the following disadvantages:

a) when a precious metal is deposited from steam, a significant amount is lost, deposited on the walls of the vacuum chamber and on various elements located inside the chamber; b) due to the fact that the coating is thin (~ 1 μm), it can be pressed through if applied to a soft substrate, and thereby be destroyed.

Known wear-resistant protective and decorative coating of the product, containing several inner layers, representing various solid phases of the titanium-nitrogen system; then a layer of gold or its alloy is deposited on the surface of these layers [3 application No. 61-231160 Japan, IPC С23С 14/06, 14/30, G04B 37/00, 1986].

The disadvantage of this coating is that although the coating is generally wear-resistant, the top layer of gold is relatively easy to erase, so for a long-term operation of the product with this coating it is necessary to apply a sufficiently thick layer of gold or its alloy. In addition, there are large losses of gold due to its deposition on the walls of the chamber and on the elements inside it. This all significantly increases the cost of the product.

The closest in technical essence and the achieved result to the proposed one is a wear-resistant protective and decorative coating on a titanium substrate containing the following layers: an inner layer of titanium in contact with the substrate, an inner layer of gold or its alloy, an upper layer of a titanium compound having a color of gold, in particular titanium oxide [Application No. JP 2003105561]. All layers are applied by physical deposition in vacuum (PVD).

Obtaining these coatings is carried out by sequentially performing the following operations:

The purified sample is placed in the working chamber (RC) of the vacuum installation:

1. RK is evacuated, after which gaseous argon is introduced into it.

2. The method of electron beam evaporation of titanium on the sample is applied to a layer of titanium with a thickness of 0.2 to 0.5 microns.

3. By the method of physical deposition in vacuum (PVD) - electron beam evaporation of gold or its alloy, a layer of gold or its alloy is applied with a thickness of 0.1 to 0.2 microns.

4. Argon is removed from the SC and gaseous oxygen is introduced.

5. Using electron beam evaporation of titanium by the method of activated reactive deposition, an upper layer of titanium oxide is deposited with a thickness of 0.3 to 0.5 μm having a color of gold.

Such coatings have the following disadvantages:

1. The surface layer of the coating does not contain gold or its alloy, which significantly limits the scope of this coating, in particular titanium oxide is not a biocompatible material and can cause allergies.

2. Since the solid titanium oxide layer is thin (from 0.3 to 0.5 μm) and deposited on a relatively soft metal, this layer can be pressed through.

3. Metal layers deposited by electron beam evaporation usually have insufficient adhesion to the substrate and between the metal layers.

4. When applying a layer of gold or its alloy there are large losses of gold due to its deposition on the walls of the chamber and on the elements inside it; This significantly increases the cost of the product.

These disadvantages can be eliminated by applying the multilayer thin-film protective and decorative coatings proposed below with an outer layer containing a precious metal, characterized by biocompatibility, wear resistance to abrasion and bursting, high adhesion and moderate cost of the coated product.

The technical result achieved by the invention is the possibility of obtaining coatings obtained by the following methods, characterized by biocompatibility, wear resistance to abrasion and bursting, high adhesion and moderate cost of the coated product.

To achieve this result, options for protective and decorative coatings of the product and methods for their implementation are proposed.

According to the first embodiment, a method for producing a protective and decorative coating on an article is proposed, including physical PVD deposition of an adhesive layer on a product in a vacuum, applying an inner layer to an adhesive layer and then applying an outer layer, wherein the inner layer is made of titanium nitride or zirconium nitride 1- 5 μm by PVD deposition, and the outer layer is 0.05-0.2 μm thick by implanting gold ions with an ion energy of 20-150 keV and a dose of more than 5 · 10 ¹⁷ ion / cm ² , while the adhesive layer is 0.2-0.3 thick microns are made from met alla or an alloy based on it, which is part of the material of the inner layer.

A protective and decorative coating of the product is also proposed, comprising an adhesive layer in contact with the product, an inner layer and an outer layer obtained by the method of the first embodiment.

In this protective and decorative coating of the product, the concentration of gold in the outer layer decreases from the limit on its surface to zero to the inner layer.

According to the second embodiment, a method for producing a protective and decorative coating on an article is proposed, including physical PVD deposition of an adhesive layer on a product in a vacuum, applying an inner layer to an adhesive layer and then applying an outer layer, wherein the inner layer is made of titanium nitride or zirconium nitride 1- 5 μm by PVD deposition, and the outer layer is performed by depositing a gold layer with a thickness of 0.05-0.2 μm and ion-mixing it by irradiation with gold ions with ion energies of 20-150 keV and a dose of more than 240 ion / cm ² , with ad An adhesive layer with a thickness of 0.2-0.3 μm is made of metal or an alloy based on it, which is part of the material of the inner layer.

Besides:

- a layer of gold is applied by physical deposition in a vacuum;

- a layer of gold is applied by selective electrochemical deposition;

- before applying the gold layer, the surface of the inner layer is irradiated with gold ions with an ion energy of 20-150 keV and an implantation dose greater than 10 ¹⁷ ion / cm ² .

A protective and decorative coating of the product is also proposed, comprising an adhesive layer in contact with the product, an inner layer and an outer layer obtained by the method of the second embodiment.

In this protective and decorative coating of the product, the concentration of gold in the outer layer decreases from the limit on its surface to zero to the inner layer.

Thus, several types of thin film coatings are proposed, representing the following sequence of layers:

- an adhesive layer with a thickness of 0.2-0.3 microns deposited on the substrate-product;

- the inner layer is 1-5 μm thick, which is a layer of a solid compound that mimics the color of a precious metal; for example, for gold, it is titanium nitride or zirconium nitride, as well as their combination;

- the outer layer containing a precious metal, a thickness of 0.05-0.2 microns.

The outer layer may be a surface layer of a solid compound of the inner layer, modified by implantation with precious metal ions; the concentration of the precious metal decreases from the limiting concentration near the surface of the coating to zero in the volume of the inner layer. The limiting concentration depends on the ion energy and the implantation dose and is in the range of 1-30 at. %

Also, the outer layer may be a layer of a precious metal, the atoms of which are mixed by a beam of high-energy ions of a precious metal with atoms of a solid compound of the inner layer; while the concentration of the precious metal drops from about 100% on the surface of the coating to zero in the volume of the inner layer.

In FIG. 1 shows a coating with a sequential arrangement of its layers according to the present invention.

The multilayer coating consists of an outer layer 1 containing a precious metal - gold, an inner layer 2 and an adhesive layer 3 applied to the workpiece 4.

The coating on the polished surface of the product (substrate) is carried out by performing the following sequence of operations:

1. Cleaning in an ultrasonic bath.

2. The room in the working chamber (RC) of the vacuum installation.

3. Ionic cleaning by glow discharge of the substrate surface inside the RC at a pressure of 2-3 Pa.

4. Deposition by PVD method in an argon atmosphere (pressure 0.2-0.3 Pa). An adhesive layer with a thickness of 0.2-0.3 microns. As the material of the adhesive layer, a metal (or an alloy based on it) is selected, which is part of the solid compound of the inner layer in contact with the adhesive layer, for example, in the case of titanium nitride as the material of the inner layer, titanium is selected as the material of the adhesive layer.

5. Deposition of the inner layer by the PVD method in a nitrogen atmosphere (pressure 0.4-0.5 Pa). A solid compound imitating the color of a precious metal is chosen as the material of the inner layer, for example, for gold, it is titanium nitride or zirconium nitride; layer thickness 1-5 microns; deposition temperature 300-500 ° C.

The thickness of the inner layer depends on the material of the substrate: the softer the substrate, the greater the thickness of the inner layer.

6. Application of the outer layer.

6.1. The surface of the inner layer is implanted with precious metal ions with an ion energy of 20-150 keV and an implantation dose greater than 5 · 10 ¹⁷ ion / cm ² , which leads to the creation of a gradient layer with a smooth change in the concentration of the precious metal from zero in the volume of the inner layer to a maximum concentration near coating surface; limit concentration is in the range of 1-30 at. %

6.2. Or, by any of the known methods, a layer of a precious metal with a thickness of 0.05-0.2 μm is applied to the surface of the inner layer, which is then irradiated with precious metal ions with an ion energy of 20-150 keV and an implantation dose greater than 2 · 10 ¹⁷ ion / cm ² , which leads to ionic mixing of the precious metal atoms with the atoms of the inner layer and the creation of a gradient layer with a smooth change in the concentration of the precious metal from zero in the volume of the inner layer to about 100% on the outer surface of the coating. In order to improve the adhesion of the precious metal layer to the surface of the inner layer before applying the precious metal layer, the surface of the inner layer is irradiated with precious metal ions with ion energies of 20-150 keV and an implantation dose greater than 10 ¹⁷ ion / cm ² .

6.2.1. The deposition of a layer of precious metal can be carried out both by the vacuum method of physical deposition of plasma or vapor flows generated by special sources inside the RK, and by the non-vacuum method outside the RK, for example, by selective electrochemical deposition.

The application of a layer of precious metal by a non-vacuum method is carried out, for example, as follows:

- the surface of the previously deposited inner layer is irradiated with precious metal ions;

- cooling of processed products in the Republic of Kazakhstan;

- extracting them from the Republic of Kazakhstan;

- application of a thin layer (0.05-1 microns) of the precious metal to the products by a non-vacuum method (e.g., using electrochemical metallization);

- cleaning products in an ultrasonic bath;

- placement of products in the Republic of Kazakhstan;

- processing products with a beam of high-energy ions of a precious metal.

7. Cooling products in the Republic of Kazakhstan.

8. Extracting products from the Republic of Kazakhstan.

Due to the wear resistance of the inner layer, the outer layer of gold can be quite thin and should provide (in the case when the coating is used as a protective and decorative) only the gold color of the coating. In this case, the color of the material of the inner layer should also be gold (titanium nitride or zirconium nitride). To prevent the formation of carbides and thereby preserve the color of the coating, deposition should be carried out in a vacuum chamber with oil-free pumping.

Ion implantation at the final stage of coating formation provides shine to the surface of the workpiece by texturing the outer coating layer.

Consider the advantages and disadvantages of the above options for the outer layer.

Using the outer layer according to claim 4 of the formula makes it possible to obtain a wear-resistant coating on the surface of which there is an almost pure precious metal, while the outer layer according to claim 1 provides a substantially lower concentration of the precious metal on the surface. On the other hand, applying the outer layer according to claim 4 is a more complex technological operation, because requires an additional operation - applying a layer of precious metal. This significantly increases the process time when applying this layer by selective electrochemical deposition and increases the consumption of precious metal during vacuum deposition inside the SC due to the deposition of metal on the walls of the SC and intracameral devices. The use of the vacuum method of applying a layer of precious metal is most appropriate when processing large surfaces, while the use of the non-vacuum method is advisable when simultaneously processing a large number of small items.

The wear resistance of the proposed coating is determined by the presence of an inner layer of a solid compound: titanium nitride and / or zirconium nitride. The wear resistance of these compounds, associated with their high microhardness, is confirmed by the numerous applications of these compounds as the material of wear-resistant coatings applied to metal cutting tools (see, for example, Vereshchak A.S. Workability of cutting tools with wear-resistant coatings. - M .: 1993, p. 335). The presence of a thin layer of gold does not actually change the microhardness and wear resistance of the coating.

The biocompatibility of the proposed coating is also associated with the use of titanium and / or zirconium nitrides. The biocompatibility of these compounds is confirmed by the numerous applications of these compounds as a coating material for parts and products implanted in the human body: implants (see, for example, Utility Model Certificate No. 20450 of 04.25.2001), endocardial electrodes of pacemakers (see, for example, Shaldakh Max. Pacemaking. Technical aspects of pacemaking, 1992, 256 pp.). Gold is traditionally considered a biocompatible material, so the presence of gold cannot degrade the biocompatibility of the coating.

High adhesion to the substrate is achieved using an adhesive layer.

Example 1. Obtaining a multilayer coating with an outer layer containing gold

Preliminarily cleaned in an ultrasonic bath, flat steel samples are placed in a working chamber (RC) of a vacuum arc unit equipped with two Zr electric arc evaporators and an Au high-energy ion implant.

Next, the following sequence of technological operations:

1. Cleaning the surfaces of the samples.

It is produced in an argon atmosphere at a pressure of 2.6 Pa by a glow discharge, which is ignited by applying bias voltages of 1000-1200 V to the working table.

2. Heating the samples.

Produced during operation of two evaporators equipped with Zr cathodes in an argon atmosphere at a pressure of 0.13-0.06 Pa; bias voltage on the desktop 1000-1200 V; the arc current of the evaporator is 90-110 A to a temperature of 500 ° C.

3. The deposition of the adhesive layer of Zr.

Produced during operation of two evaporators with Zr cathodes in an argon atmosphere at a pressure of 2 10 ^-2 Pa; bias voltage on the desktop 200 V; arc current of the evaporator 90 -110 A, temperature 500 ° C.

The layer thickness is 0.3 microns.

4. Deposition of the inner layer

When two evaporators are used with Zr cathodes in a nitrogen atmosphere at a pressure of (0.4-0.5) Pa, a bias voltage on the working table of 200 V, and a temperature of 500 ° C.

Layer thickness - 3 microns.

5. Obtaining the outer layer.

Au ions are implanted with an accelerating voltage of 10 kV, with a beam current of 15 mA, an implantation time of 5 minutes, which corresponds to an implantation dose of 0.7 · 10 ¹⁷ ion / cm ² . It was taken into account that Au ions are characterized by an average charge of 2, so that the average ion energy is 20 keV.

6. Cooling products in the Republic of Kazakhstan.

7. Extraction of products from the Republic of Kazakhstan.

Sample research:

1. The distribution of Au concentration in depth from the surface of the sample was carried out on a PHI Versa Probe II photoelectron spectrometer with a monochromatic scanning x-ray source (radiation - K _α Al). Profiling in depth was carried out using an ion argon gun (0.5 kV, the size of the etching region -1 cm ² ). High-resolution Au spectra were taken at every 10 nm. Depth change in Au concentration is shown in FIG. 2, from which it follows that the maximum concentration of Au is observed near the surface of the sample and is equal to 11.5 at. % With increasing depth, the Au concentration monotonically decreases and reaches 8 at. % at a depth of 100 nm.

2. The microhardness Hμ of the coating was determined on a Polivar Met microhardness meter of Reicher-Jung company (Austria) with a load on the diamond indenter of 5-100 g at no less than 5-10 points on the surface of the coated plate.

The obtained value Нµ = 17.3 GPa exceeds the corresponding value for the bulk sample ZrN (Нµ = 15.2 GPa). This indicates high strength properties of the coating.

3. To determine the adhesion strength, a Scratch-Tester scribing device from CSEM REVETEST was used.

The obtained adhesion value is 65 N, which indicates a high adhesion strength of the coating to the substrate.

Example 2. Obtaining a multilayer coating with an outer layer containing gold.

This example differs from example 1 only in the method of obtaining the outer layer, so that operations 1-4 of example 1 are repeated.

Obtaining the outer layer is as follows:

5.1. After applying an inner layer of zirconium nitride with a thickness of 3 μm, its surface is treated with a beam of gold ions with an accelerating voltage of 20 kV, with a beam current of 20 mA, an implantation time of 5 min, which corresponds to an implantation dose of 10 ¹⁷ ion / cm ² .

5.2. Cooling samples in the Republic of Kazakhstan.

5.3. Extracting samples from the RK.

5.4. Application by selective electrochemical deposition of an Au layer 0.05 μm thick.

5.5. Cleaning samples in an ultrasonic bath

5.6. Samples are placed in the RK, the chamber is evacuated.

5.7. Cleaning the surfaces of the samples using a glow discharge is carried out similarly to operation 1 in example 1.

5.8. The samples are treated with an Au ion beam with an accelerating voltage of 20 kV, with a beam current of 20 mA, an implantation time of 15 min, which corresponds to an implantation dose of 2.8 · 10 ¹⁷ ion / cm ² .

Analogously to example 1, the final operations are cooling products in the Republic of Kazakhstan and removing products from the Republic of Kazakhstan. Research samples.

The depth concentration of Au was carried out by the method described above. The change in Au concentration in depth from the surface of the sample is shown in FIG. 3, from which it follows that the maximum concentration of Au is observed on the surface of the sample and is equal to 100 at. % At the boundary of the deposited Au layer and the inner layer, a sharp decrease in the Au concentration is observed, after which a monotonic decrease in the Au concentration with depth is observed.

Microhardness and adhesion were determined using the methods described above. Received: Нµ = 17.2 GPa, adhesion is 65 N.

Using the present invention allows to obtain a wear-resistant protective and decorative coating with an outer layer containing a precious metal (gold) having the color of this precious metal; the coating is characterized by abrasion resistance, biocompatibility, high adhesion and moderate cost of the coated product.

Claims (9)

1. The method of obtaining a protective and decorative coating on the product, including physical PVD deposition in vacuum of the adhesive layer on the product, applying the inner layer to the adhesive layer and then performing the outer layer, characterized in that the inner layer is applied from titanium nitride or zirconium nitride with a thickness of 1- 5 μm by PVD deposition, and the outer layer is 0.05-0.2 μm thick by implanting gold ions with ion energies of 20-150 keV and a dose of more than 5 · 10 ¹⁷ ion / cm ² , while the adhesive layer is 0.2 thick -0.3 microns made of metal or alloy based on it, which is part of the material of the inner layer. 2. Protective and decorative coating of the product containing the adhesive layer in contact with the product, the inner layer and the outer layer, characterized in that it is obtained by the method according to p. 1. 3. The protective and decorative coating of the product according to claim 2, characterized in that the concentration of gold in the outer layer decreases from the limit on its surface to zero to the inner layer. 4. A method of obtaining a protective and decorative coating on an article, including physical PVD deposition in vacuum of an adhesive layer on an article, applying an inner layer to an adhesive layer and then performing an outer layer, characterized in that the inner layer is made of titanium nitride or zirconium nitride with a thickness of 1- 5 μm by PVD deposition, and the outer layer is performed by applying a gold layer with a thickness of 0.05-0.2 μm and ion-mixing it by irradiation with gold ions with ion energies of 20-150 keV and a dose of more than 2 · 10 ¹⁷ ion / cm ² , at this adhesive layer 0.2-0.3 microns thick made of metal or alloy thereof constituting the inner layer material. 5. The method according to p. 4, characterized in that the gold layer is applied by physical deposition in a vacuum. 6. The method according to p. 4, characterized in that the gold layer is deposited by selective electrochemical deposition. 7. The method according to p. 4, characterized in that before applying the gold layer, the surface of the inner layer is irradiated with gold ions with an ion energy of 20-150 keV and an implantation dose greater than 10 ¹⁷ ion / cm ² . 8. Protective and decorative coating of the product containing the adhesive layer in contact with the product, the inner layer and the outer layer, characterized in that it is obtained by the method according to one of claims. 4-7. 9. The protective and decorative coating of the product according to claim 8, characterized in that the concentration of gold in the outer layer decreases from the limit on its surface to zero to the inner layer.

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