CN114959696B

CN114959696B - Hard coating, preparation method and application thereof

Info

Publication number: CN114959696B
Application number: CN202210468664.5A
Authority: CN
Inventors: 陈娜; 孙世棚; 石敏艺
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2022-04-29
Filing date: 2022-04-29
Publication date: 2023-06-23
Anticipated expiration: 2042-04-29
Also published as: CN114959696A

Abstract

The invention relates to the field of coatings, in particular to a hard coating and a preparation method and application thereof. The hard coating comprises a first amorphous metal oxide layer, a second amorphous metal oxide layer and an amorphous alloy layer which are arranged in a laminated manner, wherein the first amorphous metal oxide layer is positioned on the outermost layer; the element composition of the first amorphous metal oxide layer comprises Ti, zr, nb, si and O, the element composition of the second amorphous metal oxide layer comprises a first transition metal, a first rare metal, B and O, the first rare metal is Ta and/or Nb, the first transition metal is Co or Fe, the element composition of the amorphous alloy layer comprises a second transition metal, a second rare metal and B, the second rare metal is Ta and/or Nb, and the second transition metal is Co and/or Fe. The hard coating provided by the invention has excellent hardness, wear resistance and biocompatibility.

Description

Hard coating, preparation method and application thereof

Technical Field

The invention relates to the field of coatings, in particular to a hard coating and a preparation method and application thereof.

Background

Along with the progress of technology and the development of society, the development of small, multifunctional and highly integrated devices or equipment has become a development direction meeting the important requirements in the modern high-tech field, such as the IT field including mobile phones, computers and the like, micro-nano photoelectric devices, automobiles, medical appliances, oil and gas pipelines, power generation, oil drilling, pharmaceutical chemicals, coal and the like, and has very important application prospects, wherein the multifunctional coating material is one of key supporting materials. The coating is coated on the base material, so that the appearance of the base material is selective, and the ornamental value of the base material is improved; on the other hand, the existence of the coating can improve the wear resistance, the surface quality and the like of the matrix material, and particularly has strict requirements on the biocompatibility of the contact surface material of a wearable device or equipment in direct contact with a human body, however, the existing coating material is difficult to simultaneously meet the requirements on the multifunctional characteristics such as high hardness, excellent wear resistance, flexibility, corrosion resistance, biocompatibility and the like.

Disclosure of Invention

Based on the above, the invention provides the hard coating which is rich in color and has high strength, high hardness, excellent wear resistance and biocompatibility, and the preparation method and the application thereof.

In one aspect of the present invention, there is provided a hard coating layer including a first amorphous metal oxide layer, a second amorphous metal oxide layer, and an amorphous alloy layer, which are stacked, and the first amorphous metal oxide layer is located at an outermost layer of a stacked structure; the elemental composition of the first amorphous metal oxide layer comprises Ti, zr, nb, si and O, the elemental composition of the second amorphous metal oxide layer comprises a first transition metal comprising Ta and/or Nb, a first rare metal comprising Co or Fe, B and O, the elemental composition of the amorphous alloy layer comprises a second transition metal comprising Ta and/or Nb, and a second rare metal comprising Co and/or Fe.

Optionally, the material of the first amorphous metal oxide layer comprises (Ti, zr, nb, si) _100-x O _x Wherein 60 < x < 100.

Optionally, the element composition of the second amorphous metal oxide layer includes Co, ta, B, and O, as described above for the hard coating.

Optionally, the element composition of the second amorphous metal oxide layer includes Fe, nb, B and O as the hard coating described above.

Optionally, the material of the second amorphous metal oxide layer comprises (Co, ta, B) _100-y O _y Wherein 35 is<y<100。

Optionally, the material of the second amorphous metal oxide layer comprises (Fe, nb, B) _100-z O _z Wherein 35 is<z<100。

Optionally, the element composition of the amorphous alloy layer includes Co, ta, and B, as described above for the hard coating layer.

Optionally, as the hard coating layer, the element composition of the amorphous alloy layer includes Fe, nb, and B.

Optionally, as described above, the element composition of the amorphous alloy layer further includes an oxygen element, and the mass percentage of the oxygen element is less than 35%.

Optionally, as described above, the number of layers of the first amorphous metal oxide layer, the second amorphous metal oxide layer, and the amorphous alloy layer is 1 to 100 independently;

the thickness of each of the first amorphous metal oxide layer, the second amorphous metal oxide layer, and the amorphous alloy layer is independently 0.01 μm to 10 μm.

In an aspect of the present invention, there is further provided a method for preparing the hard coating, which includes forming the first amorphous metal oxide layer, the second amorphous metal oxide layer and the amorphous alloy layer in a stacked arrangement, where the first amorphous metal oxide layer is formed on an outermost layer of the stacked structure.

Optionally, the method for preparing a hard coating as described above further comprises the steps of providing a substrate and forming a bonding layer on the substrate, wherein the bonding layer is used for bonding the substrate and the hard coating.

In another aspect of the invention, there is further provided the use of a hard coating as described above for the preparation of an electronic device, an optoelectronic device, a medical instrument, a wearable device or an engineering pipeline.

The invention forms the hard coating with the multifunctional characteristics of excellent strength, hardness, wear resistance, biocompatibility, rich colors and the like by laminating the first amorphous metal oxide layer with biocompatibility, the second amorphous metal oxide layer with different colors and the amorphous alloy layer with excellent wear resistance and high hardness. The thickness and the wear resistance of the formed hard coating can be equivalent to or even higher than the currently industrialized TiN coating or WC coating; and the thickness of the hard coating can reach more than 10 mu m, which is far higher than that of the traditional wear-resistant coating or hard coating (the thickness of the TiN coating or WC coating is usually less than 2 mu m). Compared with the traditional wear-resistant coating, the toughness and the service life of the hard coating are better. In addition, the hard coating layer has excellent biocompatibility, which can be similar to or better than that of pure titanium.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a photograph of a yellow coating prepared in example 3 of the present invention;

FIG. 2 is an XRD pattern of the yellow coating obtained in example 3 of the present invention;

FIG. 3 is a graph showing transmittance of the yellow coating prepared in example 3 of the present invention;

FIGS. 4 to 6 are pictures of the coatings produced in examples 4 to 6 of the present invention;

FIG. 7 is a graph showing the reflectance spectrum of the coatings produced in examples 3 to 6 of the present invention;

FIG. 8 is a photograph of an iridescent coating prepared in example 7 of the present invention;

FIG. 9 is an XRD pattern of the first amorphous metal oxide layer in the hard coating layer prepared in example 8 of the present invention;

FIG. 10 shows the results of a biocompatibility test for the hard coat layer prepared in example 8 of the present invention.

Detailed Description

Reference now will be made in detail to embodiments of the invention, one or more examples of which are described below. Each example is provided by way of explanation, not limitation, of the invention. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope or spirit of the invention. For example, features illustrated or described as part of one embodiment can be used on another embodiment to yield still a further embodiment.

Accordingly, it is intended that the present invention cover such modifications and variations as fall within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present invention will be disclosed in or be apparent from the following detailed description. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

The invention relates to a hard coating, which comprises a first amorphous metal oxide layer, a second amorphous metal oxide layer and an amorphous alloy layer which are stacked, wherein the first amorphous metal oxide layer is positioned at the outermost layer of a stacked structure;

wherein the elemental composition of the first amorphous metal oxide layer comprises Ti, zr, nb, si and O; the element composition of the second amorphous metal oxide layer comprises a first transition metal, a first rare metal, B and O, wherein the first rare metal is Ta and/or Nb, the first transition metal is Co or Fe, and the second transition metal is Co or Fe; the element composition of the amorphous alloy layer comprises a second transition metal, a second rare metal and B, wherein the second rare metal is Ta and/or Nb, and the second transition metal is Co and/or Fe.

The first amorphous metal oxide layer has excellent biocompatibility through specific element composition, the second amorphous metal oxide layer has rich color change function, and the amorphous alloy layer has excellent hardness, strength and wear resistance. The thickness and wear resistance of the hard coating formed by arranging the three coating stacks can be equivalent to or even higher than that of the TiN coating or WC coating which is industrialized at present; and the thickness of the hard coating can reach more than 10 mu m, which is far higher than that of the traditional wear-resistant coating or hard coating (the thickness of the TiN coating or WC coating is usually less than 2 mu m). Compared with the traditional wear-resistant coating, the toughness and the service life of the hard coating are better. In addition, the hard coating layer has excellent biocompatibility, which can be similar to or better than that of pure titanium.

In some embodiments, the band gap of the second amorphous metal oxide layer may be any value between 3.5eV and 5.5eV, for example, 4eV, 4.2eV, 4.5eV, 4.8eV, 5eV. The band gap of the second amorphous metal oxide layer is 3.5 eV-5.5 eV, and the second amorphous metal oxide layer can be used as a light-transmitting layer material and is suitable for a color display component of an optoelectronic device. The preparation process and raw materials are simple and easy to obtain, the cost is low, the environment friendliness is achieved, and the coating can be used as an excellent protective coating to be applied to devices or equipment.

In some embodiments, the material of the first amorphous metal oxide layer comprises (Ti, zr, nb, si) _100-x O _x Wherein 60 < x < 100.

In some embodiments, the elemental composition of the second amorphous metal oxide layer includes Co, ta, B, and O. Preferably, the material of the second amorphous metal oxide layer comprises (Co, ta, B) _100-y O _y Wherein 35 is<y<100. In other embodiments, the elemental composition of the second amorphous metal oxide layer includes Fe, nb, B, and O. Preferably, the material of the second amorphous metal oxide layer comprises (Fe, nb, B) _100-z O _z Wherein 35 is<z<100. The color of the hard coat layer can be changed by changing the content of oxygen element in the second amorphous metal oxide layer.

In some embodiments, the elemental composition of the amorphous alloy layer includes Co, ta, and B. In other embodiments, the elemental composition of the amorphous alloy layer includes Fe, nb, and B.

In some embodiments, the elemental composition of the amorphous alloy layer further includes an oxygen element, and the mass percent of the oxygen element is less than 35%. By changing the oxygen element content in the amorphous alloy layer, the wear resistance, strength and hardness thereof can be changed. Preferably, the elemental composition in the amorphous alloy layer is the same as the elemental composition of the metal in the second amorphous metal oxide layer.

In some embodiments, the number of first amorphous metal oxide layers may be 1 to 100; wherein the thickness of each of the first amorphous metal oxide layers may be 0.01 μm to 1 μm.

In some embodiments, the number of second amorphous metal oxide layers may be 1 to 100. Wherein the thickness of each of the second amorphous metal oxide layers may be 0.01 μm to 1 μm. The color of the hard coat layer may be changed by changing the number of layers or thickness of the second amorphous metal oxide layer. And the second amorphous metal oxide layer may have a continuously varying thickness or a continuously varying number of layers from one side of the hard coating layer to the other, thereby imparting a graded color to the hard coating layer.

In some embodiments, the number of amorphous alloy layers may be 1 to 100. Wherein the thickness of each amorphous alloy layer may be 0.05 μm to 10 μm. The wear resistance, hardness and strength of the amorphous alloy layer can be changed by changing the number of layers or the thickness of the amorphous alloy layer.

In some embodiments, the amorphous alloy layer may also be provided with a first amorphous metal oxide layer on a side facing away from the second amorphous metal oxide layer to improve its bonding with the titanium-containing substrate.

In some embodiments, the second amorphous metal oxide layer and the amorphous alloy layer are each a plurality of layers, and the second amorphous metal oxide layer and the amorphous alloy layer are alternately stacked.

In one aspect of the present invention, a method for preparing the hard coating layer is provided, which includes forming a first amorphous metal oxide layer, a second amorphous metal oxide layer and an amorphous alloy layer that are stacked, where the first amorphous metal oxide layer is formed on an outermost layer of the stacked structure.

In some embodiments, the process of preparing the hard coating may be any known coating preparation technique commonly used in the art, for example, may be a magnetron sputtering technique. The vacuum degree of the specific magnetron sputtering chamber is about 10 ^-4 Pa, the high-purity gas can be argon or a mixed gas of argon and oxygen, and the gas pressure can be 0.4Pa. Wherein, the high purity refers to the purity of more than or equal to 99.999 weight percent.

In some embodiments, the method of making further comprises the steps of providing a substrate and forming a tie layer on the substrate, the tie layer being used to bond the substrate to the hardcoat layer.

In some embodiments, the substrate is not particularly limited, and may be any substrate commonly used in the art, for example, a substrate such as a semiconductor, a polymer substrate, or a metal substrate. Wherein, the metal substrate can be a stainless steel or titanium alloy substrate.

In some embodiments, the material of the adhesive layer is not limited, so that the amorphous alloy layer and the substrate can form good adhesion. Preferably, the bonding layer is a nano diphase amorphous layer, and the nano diphase amorphous layer comprises an amorphous alloy with the same element type as the amorphous alloy layer or an amorphous metal oxide with the same element type as the second amorphous metal oxide layer. The same elements are selected to omit the step of changing the target material in the process of preparing the coating, so that the production efficiency of the hard coating can be improved, the influence on the integral quality of the hard coating caused by pollution to the surface of the amorphous alloy layer or the second amorphous metal oxide layer in the process of changing the target material is avoided, and the quality of the hard coating is improved. The thickness of the bonding layer is not limited in the invention, and can be adjusted according to the actual requirement of the product so as to realize good bonding between the substrate and the amorphous alloy layer.

In some embodiments, the target composition for forming the first amorphous metal oxide layer is Ti _a Zr _b Nb _c Si _d Wherein a, b, c and d are all atomic percentages, a is more than or equal to 0 and less than or equal to 86,0, b is more than or equal to 91,0, c is more than or equal to 82.5,9 and d is more than or equal to 86.

In some embodiments, the target composition for forming the second amorphous metal oxide layer is Co _n Ta _m B _k Wherein n, m and k are all atomic percentages, n is more than or equal to 35 and less than or equal to 80, m is more than or equal to 5 and less than or equal to 25, and k is more than or equal to 15 and less than or equal to 45.

In some embodiments, the target composition for forming the second amorphous metal oxide layer is Fe _w Nb _r B _t Wherein w, r and t are atomic percentages, w is more than or equal to 35 and less than or equal to 80, r is more than or equal to 5 and less than or equal to 25, and t is more than or equal to 15 and less than or equal to 45.

In some embodiments, the target composition for forming the amorphous alloy layer may be Co _q Ta _u B _p Wherein q, u and p are atomic percentages, q is more than or equal to 35 and less than or equal to 80, u is more than or equal to 5 and less than or equal to 25, and p is more than or equal to 15 and less than or equal to 45.

In some embodiments, the target composition for forming the amorphous alloy layer may be Fe _s Nb _g B _j Wherein s, g and j are all atomic percent, and s is more than or equal to 35 and less than or equal to s80，5＜g≤25，15≤j≤45。

Preferably, the composition of the target material for forming the second amorphous metal oxide layer and the composition of the target material for forming the amorphous alloy layer are the same, so that the same alloy target material can be ensured to be used in the preparation process, the step of changing the target material is avoided, the production efficiency is improved, the influence on the integral quality of the hard coating due to pollution to the surface of the bonding layer and the surface of the amorphous alloy layer in the process of changing the target material is avoided, the quality of the hard coating is improved, the operation process is simplified, and the mass production of the hard coating is facilitated.

In some embodiments, the method for preparing the hard coating may specifically include the steps of:

placing a first alloy target and a substrate in a closed chamber;

introducing inert gas and oxygen into the chamber to enable the oxygen to react with target atoms of the first alloy target after gasification, and forming a nano diphase amorphous layer on the substrate;

closing oxygen, gasifying the first alloy target in inert atmosphere and forming an amorphous alloy layer on the nano diphase amorphous layer;

opening oxygen, regulating and controlling the partial pressure ratio of inert gas and oxygen in the chamber, so that the oxygen reacts with target atoms gasified by the first alloy target, and forming a second amorphous metal oxide layer on the amorphous alloy layer;

and replacing the first alloy target with a second alloy target, regulating and controlling the partial pressure ratio of inert gas and oxygen in the chamber, so that the oxygen reacts with target atoms gasified by the second alloy target, and forming a first amorphous metal oxide layer on the second amorphous metal oxide layer.

The present invention will be described in further detail with reference to specific examples.

Example 1 preparation of amorphous alloy layer

Alloy target material with Co-Ta-B as raw material is selected, and is not selectedAnd (3) placing the target and the substrate into a chamber of the magnetron sputtering device together with the stainless steel substrate. Pre-evacuating the chamber to 10 ^-4 And (3) introducing argon and oxygen below Pa, adjusting the partial pressure ratio of the oxygen to the argon to be 0.01, and sputtering under a mixed atmosphere to obtain the bonding transition layer (namely the nano diphase amorphous layer) with the thickness of 50 nm. The oxygen was then turned off and an amorphous alloy layer about 2 μm thick was sputtered under a pure argon atmosphere. The hardness of the amorphous alloy layer was about 10GPa and the elastic modulus was about 153GPa as shown in table 1.

TABLE 1

Number of tests	Elastic modulus (GPa)	Hardness (GPa)
			1	163.5	12.26
2	153.6	10.88
			3	142.4	9.39
Average value of	153.1	10.84
			Standard deviation of	10.5	1.44

Example 2 preparation of amorphous alloy layer

The preparation method of this example is basically the same as that of example 1, except that: alloy targets are different. The method comprises the following specific steps:

alloy targets with the components of Fe-Nb-B are selected as raw materials, a stainless steel substrate is selected, and the targets and the substrate are put into a chamber of a magnetron sputtering device together. Pre-evacuating the chamber to 10 ^-4 And (3) introducing argon and oxygen below Pa, adjusting the partial pressure ratio of the oxygen to the argon to be 0.01, and sputtering under a mixed atmosphere to obtain the bonding transition layer (namely the nano diphase amorphous layer) with the thickness of 50 nm. The oxygen was then turned off and an amorphous alloy layer about 2 μm thick was sputtered under a pure argon atmosphere.

Example 3 preparation of yellow coating

Selecting an alloy target material with a component of Co-Ta-B as a raw material, and placing the amorphous alloy layer prepared in the embodiment 1 into a chamber of a magnetron sputtering device; pre-evacuating the chamber to 10 ^-4 Introducing argon and oxygen below Pa, adjusting the partial pressure ratio of the oxygen and the argon to 0.053, and sputtering on the amorphous alloy layer to obtain a second amorphous metal oxide layer with the thickness of 180nm, wherein the composition of the second amorphous metal oxide layer is (Co, ta, B) _51.70 O _48.30 Thus, a yellow coating as shown in fig. 1 was produced. As shown in fig. 2, when XRD test is performed, the second amorphous metal oxide layer is truly amorphous. Referring to fig. 3, the transmittance of the coating prepared in this example is higher.

EXAMPLE 4 preparation of a rose-red coating

The preparation method of this example is basically the same as that of example 2, except that: the second amorphous metal oxide layer has a different thickness. The method comprises the following specific steps:

selecting an alloy target material with a component of Co-Ta-B as a raw material, and placing the amorphous alloy layer prepared in the embodiment 1 into a chamber of a magnetron sputtering device; pre-evacuating the chamber to 10 ^-4 Argon and oxygen are introduced below Pa, and the oxygen and the argon are regulatedThe gas partial pressure ratio was 0.053, and a second amorphous metal oxide layer with a thickness of 215nm was sputtered on the amorphous alloy layer, the second amorphous metal oxide layer having a composition of (Co, ta, B) _51.70 O _48.30 Thus, a rose-red coating as shown in fig. 4 was produced.

Example 5 preparation of blue coating

selecting an alloy target material with a component of Fe-Nb-B as a raw material, and placing the amorphous alloy layer prepared in the embodiment 1 in a chamber of a magnetron sputtering device; pre-evacuating the chamber to 10 ^-4 Introducing argon and oxygen below Pa, adjusting the partial pressure ratio of the oxygen and the argon to 0.053, and sputtering on the amorphous alloy layer to obtain 257nm thick second amorphous metal oxide layer with the composition of (Fe, nb, B) ₄₅ O ₅₅ Thus, a blue coating as shown in fig. 5 was produced.

Example 6 preparation of Green coating

selecting an alloy target material with a component of Co-Ta-B as a raw material, and placing the amorphous alloy layer prepared in the embodiment 1 into a chamber of a magnetron sputtering device; pre-evacuating the chamber to 10 ^-4 Introducing argon and oxygen below Pa, adjusting the partial pressure ratio of the oxygen and the argon to 0.053, and sputtering on the amorphous alloy layer to obtain a 305nm thick second amorphous metal oxide layer with the composition of (Co, ta, B) _51.70 O _48.30 Thus, a green coating as shown in fig. 6 was produced. As can be seen from fig. 7, the coatings of different colors and thicknesses prepared in examples 2 to 5 are capable of reflecting light waves of different wavelengths, i.e., different reflectivities for light of different colors.

EXAMPLE 7 preparation of iridescent coating

selecting an alloy target material with a component of Co-Ta-B as a raw material, and placing the amorphous alloy layer prepared in the embodiment 1 into a chamber of a magnetron sputtering device; pre-evacuating the chamber to 10 ^-4 Introducing argon and oxygen below Pa, regulating the partial pressure ratio of the oxygen and the argon to 0.053, and continuously sputtering on the amorphous alloy layer to obtain a second amorphous metal oxide layer with the thickness of 170 nm-300 nm, wherein the composition of the second amorphous metal oxide layer is (Co, ta, B) _51.70 O _48.30 Thus, an iridescent coating as shown in fig. 8 was produced.

EXAMPLE 8 preparation of hard coating

Selecting an alloy target material with a component of Ti-Zr-Nb-Si as a raw material, and placing the yellow coating prepared in the embodiment 2 in a chamber of a magnetron sputtering device; pre-evacuating the chamber to 10 ^-4 Argon is introduced under Pa, and Ti with the thickness of 350nm is obtained after sputtering for 60min ₃₀ Zr ₄ Nb ₇ Si ₇ O ₅₂ The first amorphous metal oxide layer of (2) to obtain the hard coating. The XRD pattern of the first amorphous metal oxide layer is shown in fig. 9. As can be seen from fig. 9, the first amorphous metal oxide layer is amorphous. The coating was tested for biocompatibility as shown in fig. 10. As can be seen from fig. 10, the first amorphous metal oxide layer has biocompatibility similar to that of pure titanium, in contrast to pure titanium.

As can be seen from the characterization results of the above embodiments, the hard coating provided by the invention has rich colors, high wear resistance, high hardness and excellent biocompatibility.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims

1. The hard coating is characterized by comprising a first amorphous metal oxide layer, a second amorphous metal oxide layer and an amorphous alloy layer which are sequentially laminated, wherein the first amorphous metal oxide layer is positioned at the outermost layer of the laminated structure; the material of the first amorphous metal oxide layer comprises (Ti, zr, nb, si) _100-x O _x Wherein 60 < x < 100, the material of the second amorphous metal oxide layer comprises (Co, ta, B) _100-y O _y Wherein 35 is<y<100; or the material of the second amorphous metal oxide layer comprises (Fe, nb, B) _100-z O _z Wherein 35 is<z<100, wherein the element composition of the amorphous alloy layer comprises a second transition metal, a second rare metal, an oxygen element and B, the second rare metal is Ta and/or Nb, the second transition metal is Co and/or Fe, and the mass percentage of the oxygen element is less than 35%.

2. The hard coat according to claim 1, wherein the amorphous alloy layer has an elemental composition of Co, ta, O, and B; or (b)

The amorphous alloy layer has the element composition of Fe, nb, O and B.

3. The hard coat according to any one of claims 1 to 2, wherein the number of layers of the first amorphous metal oxide layer, the second amorphous metal oxide layer, and the amorphous alloy layer is 1 to 100 each independently;

the thickness of each of the first amorphous metal oxide layer, the second amorphous metal oxide layer and the amorphous alloy layer is respectively and independently 0.01-10 mu m.

4. A method of producing a hard coating according to any one of claims 1 to 3, comprising forming the first amorphous metal oxide layer, the second amorphous metal oxide layer, and the amorphous alloy layer in a stacked arrangement, wherein the first amorphous metal oxide layer is formed on an outermost layer of the stacked structure.

5. The method of claim 4, further comprising the steps of providing a substrate and forming a bonding layer on the substrate, the bonding layer being used to bond the substrate to the hard coating.

6. Use of a hard coating according to any one of claims 1 to 3 for the preparation of electronic devices, optoelectronic devices, medical devices, wearable devices or engineering pipelines.