CN109609953B

CN109609953B - Ultra-limit copper alloy and preparation method thereof

Info

Publication number: CN109609953B
Application number: CN201811645724.6A
Authority: CN
Inventors: 冯晶; 吴福硕; 宋鹏; 种晓宇; 葛振华
Original assignee: Kunming University of Science and Technology
Current assignee: Kunming University of Science and Technology
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2020-01-14
Anticipated expiration: 2038-12-29
Also published as: CN109609953A

Abstract

The invention belongs to the technical field of copper alloy material preparation, and discloses an ultra-limit copper alloy and a preparation method thereof, wherein the ultra-limit copper alloy comprises a copper alloy matrix, and a composite bonding layer, a composite ceramic layer, a reflecting layer, a catadioptric layer, an insulating layer and a foam carbon layer are sequentially deposited on the surface of the copper alloy matrix; the composite bonding layer comprises a bonding layer deposited on the surface of the copper alloy substrate and a noble metal layer deposited on the surface of the bonding layer; the composite ceramic layer comprises a ceramic A layer and a ceramic B layer. According to the invention, the multilayer coating is deposited on the surface of the copper alloy substrate, so that the use temperature of the copper alloy substrate can be raised to be higher than the melting point of the original copper alloy substrate by 100-. The ultra-limit copper alloy provided by the invention has excellent high-temperature mechanical and chemical stability, can be used under the condition of exceeding the melting point of the copper alloy matrix, and increases the application range.

Description

Ultra-limit copper alloy and preparation method thereof

Technical Field

The invention belongs to the technical field of preparation of copper alloy materials, and particularly relates to an ultra-limit copper alloy and a preparation method thereof.

Background

Copper alloy is an important metal material at present, and refers to an alloy which takes copper as a matrix and is added with other elements. Copper has good mechanical, physical and chemical properties, and copper alloy formed by adding proper elements into copper has strong oxidation resistance, corrosion resistance and high-temperature strength and can improve certain physical properties, so the copper alloy is widely used in the fields of energy development, chemical industry, electronics, navigation, aviation and aerospace. The copper alloy has strong comprehensive properties such as strength, hardness, shock resistance, corrosion resistance, oxidation resistance, high-temperature strength, certain physical properties and the like, and plays an irreplaceable role in the field of aerospace. For example: the inner lining of the combustion chamber and thrust chamber of a rocket engine can be cooled by utilizing the excellent thermal conductivity of copper so as to ensure that the temperature of the engine is in an allowable range. The combustion chamber liner of the No. 5 Arira rocket adopts copper-silver alloy, 360 cooling channels are processed in the liner, and liquid hydrogen is introduced for cooling when the rocket is launched.

With the development of technology and the practical requirements of society, the speed requirement of aircrafts is higher and higher, the speed increase of aircrafts means that the running speed of an engine is gradually increased, so that the surface temperature of engine blades is gradually increased, and although copper alloy has many excellent properties, the use of copper alloy under high temperature conditions is greatly limited due to the characteristic that the melting point of copper alloy is about 1080 ℃ and the copper alloy is easily oxidized at high temperature. In addition, when the metal is operated at a temperature exceeding half of its melting point, softening occurs, that is, when the copper alloy is operated at 540 ℃, softening occurs and the performance is lowered. The current copper alloy can not meet the use requirement of the accelerated aircraft (namely, the copper alloy can not be used at the ultra-limit temperature (exceeding the melting point temperature of the copper alloy)), or the service life of the aircraft must be sacrificed in order to meet the requirement of the accelerated aircraft. Therefore, the development of the aircraft and even the development of the whole copper alloy are limited, and the use of the copper alloy is limited, so that the bottleneck is reached.

Disclosure of Invention

The invention aims to provide an ultra-limit copper alloy and a preparation method thereof, and aims to solve the problem that the existing copper alloy cannot be used at an ultra-limit temperature.

To achieve the above object, the present invention provides the following basic solutions:

the ultra-limit copper alloy comprises a copper alloy matrix, wherein a composite bonding layer and a composite ceramic layer are sequentially deposited on the surface of the copper alloy matrix; the composite bonding layer comprises a bonding layer deposited on the surface of the copper alloy substrate and a noble metal layer deposited on the surface of the bonding layer; the composite ceramic layer comprises a ceramic A layer and a ceramic B layer.

The beneficial effects of the technical scheme are as follows:

through extensive research, the inventor develops an ultra-limit copper alloy which meets the requirement that the copper alloy is used at an ultra-limit temperature (exceeding the melting point temperature). In the development process, people generally consider that when the ambient temperature is higher than the use temperature of the alloy, the alloy cannot be used at the temperature, and other high-melting-point alloys are required to be used, and the inventors do not go so far and try to improve the copper alloy to meet the requirements of aircraft manufacturing. In the process of continuous trial by the inventor, the inventor discovers that the use temperature of the copper alloy can be increased to be higher than the original melting point by 100-500 ℃ by depositing a coating with a certain proportion on the surface of the copper alloy, so that the use temperature of the copper alloy can be greatly increased, and the requirement of manufacturing an aircraft can be met; in a high-temperature environment, the use temperature of the copper alloy is difficult to be raised by 2-3 ℃, so that the research of the applicant is a great progress on the use of the copper alloy.

According to the technical scheme, the composite bonding layer and the composite ceramic layer are deposited on the copper alloy substrate, so that the use temperature of the copper alloy can be greatly improved, and the copper alloy is suitable for being used under the condition of exceeding the limit temperature. The composite bonding layer is deposited, so that the bonding effect between each coating and the copper alloy matrix can be improved, and the coating is prevented from falling off in the using process. The composite ceramic layer is deposited, so that the heat conduction can be reduced, and the service temperature of the copper alloy matrix can be increased. According to the technical scheme, the service temperature of the copper alloy is greatly improved through the matching of the coatings.

In summary, the present invention has the following technical effects:

1. the ultra-limit copper alloy provided by the invention has excellent high-temperature mechanical and chemical stability, can be used under the condition of exceeding the melting point of the copper alloy matrix, and increases the application range.

2. According to the invention, the multilayer coating is deposited on the surface of the copper alloy substrate, so that the use temperature of the copper alloy substrate can be raised to be higher than the melting point of the original copper alloy substrate by 100-.

3. The ultra-limit copper alloy provided by the invention has excellent corrosion resistance, so that the service time under acidic or alkaline conditions is greatly increased, the waste caused by material corrosion can be reduced, and the cost is saved.

4. The ultra-limit copper alloy provided by the invention breaks through the development bottleneck of the traditional copper alloy, the use temperature of the copper alloy can be further improved on the basis of higher melting point, and the improved temperature is a dramatic progress. The ultra-limit copper alloy provided by the invention can be applied to preparation of engine blades of aircrafts, and can meet the use requirement of the temperature rise of the engines when the aircrafts increase the speed, thereby realizing the speed increase of the aircrafts.

Further, the thickness of the composite bonding layer is 100-200 μm, the thickness of the composite ceramic layer is 150-500 μm, and a reflecting layer with the thickness of 10-30 μm, a catadioptric layer with the thickness of 10-30 μm, an insulating layer with the thickness of 10-200 μm and a foam carbon layer with the thickness of 20-200 μm are sequentially deposited outside the composite ceramic layer.

Has the advantages that: the reflecting layer has the effect of reflecting heat sources, so that the heat sources on the surface of the copper alloy are reduced, and the use temperature is increased. The deposited catadioptric layer can block the refraction of infrared rays in the coating, thereby reducing the temperature of the copper alloy matrix and improving the service temperature of the prepared copper alloy. The effect of depositing the insulating layer is that the surface of the material is easy to ionize in the ultra-high speed environment, and the insulating layer can prevent conductive ions or electrons generated by ionization from entering the copper alloy matrix, so that the corrosion of charges to the copper alloy matrix is resisted. When in use, the carbon of the foam carbon layer is vaporized and cooled, and a vaporization film is formed on the surface of the copper alloy substrate, so that the heat transmission is further prevented, and the use temperature of the copper alloy is increased. And the thickness of each coating is set, so that the service temperature of the prepared ultra-limit copper alloy can be increased, the heat insulation effect of the coatings is ensured, the weight of the coatings is also controlled, and the aircraft can be conveniently used.

Furthermore, the bonding layer is one or a mixture of more of MCrAlY, NiAl, NiCr-Al and Mo alloy, and the MCrAlY is NiCrCoAlY, NiCoCrAlY, CoNiCrAlY or CoCrAlY; the component of the noble metal layer is one or more of Au, Pt, Ru, Rh, Pd and Ir.

Has the advantages that: in the three materials of NiCrCoAlY, NiCoCrAlY and CoNiCrAlY, the content of each element is reduced in turn according to the chemical formula, and the proportion of each element in the three materials is different, so that the prepared materials are different. The bonding layer has good bonding effect, so that the subsequent coating and the copper alloy matrix have good bonding effect, and the falling probability of the coating is reduced; the noble metal has the characteristic of oxidation resistance, and can effectively prevent oxygen from diffusing into the bonding layer and the copper alloy matrix at high temperature, so that the oxidation resistance of the coating is improved, and the service life of the coating is prolonged.

Further, the ceramic A layer contains YSZ or rare earth zirconate (RE)₂Zr₂O₇) The component of the ceramic B layer is ZrO₂-RETaO₄。

Has the advantages that: YSZ or rare earth zirconate is the most commonly used component of the ceramic layer in the current thermal barrier coating, and the preparation process is mature and convenient to purchase; and ZrO₂-RETaO₄The copper alloy has the effects of high expansion coefficient and low thermal conductivity, wherein the low thermal conductivity can reduce the conduction of external heat into the copper alloy matrix, so that the copper alloy matrix can keep a lower temperature in a high-temperature environment; for the high expansion coefficient, the coating is used as a whole and does not act singly, the high expansion coefficient is matched with the thermal expansion coefficient of the bonding layer, and the thermal mismatch stress (stress generated by different thermal expansion coefficients) of the ceramic layer and the bonding layer is small in the thermal cycle process (namely the process of continuously heating and cooling) because the thermal expansion coefficient of the noble metal bonding layer is large, so that the service life of the coating is prolonged. (colloquially, when two coatings having significantly different coefficients of thermal expansion are deposited together,when the temperature is increased or decreased, the expansion degrees of the two coatings are seriously different, so that the stress between the two coatings is increased, and the two coatings are cracked or even fall off. )

Further, the reflective layer has a composition of REVO₄、RETaO₄、Y₂O₃One or a mixture of several of them.

Has the advantages that: REVO4, RETaO4 and Y2O3 have high reflection coefficients, so that the reflection effect on heat radiation is good, the temperature of a copper alloy matrix in a high-temperature environment is greatly reduced, and the use temperature of the prepared copper alloy is improved.

Furthermore, the component of the catadioptric layer is one or a mixture of two of graphene and boron carbide, and the spatial distribution of the graphene and the boron carbide is in a disordered arrangement state.

Has the advantages that: because the spatial distribution of graphite alkene or boron carbide is the state of unordered range, though graphite alkene or boron carbide have higher refracting index, when the infrared light when shining on graphite alkene catadioptric layer, the graphite alkene of unordered range can strengthen the refraction of light in all directions, avoids the incident light to take place the refraction in same direction, reaches the effect that the refraction is dispersed, enters into the intensity decline of the infrared light in the coating like this to reduce the temperature of coating and copper alloy base member.

Further, the insulating layer is made of one or a mixture of epoxy resin, phenolic resin and ABS resin.

Has the advantages that: taking an aircraft as an example, in the process of high-speed flight, the outer surface of the aircraft rubs with air, so that the air is ionized to form conductive ions or electrons, and the inventor verifies through experiments that the adoption of organic coatings such as epoxy resin and phenolic resin can effectively resist the electric charges from entering the coatings and the copper alloy matrix, thereby reducing the corrosion of the conductive electrons or ions to tin alloy welding seams.

The invention also provides another technical scheme, and the preparation method of the ultra-limit copper alloy comprises the following steps:

step 1: depositing a bonding layer on the surface of the copper alloy substrate; depositing a noble metal layer on the surface of the bonding layer to form a composite bonding layer by the bonding layer and the noble metal layer, wherein the total thickness of the composite bonding layer is 100-200 mu m;

step 2: depositing a ceramic layer A and a ceramic layer B on the surface of the composite bonding layer obtained in the step 1 to form a composite ceramic layer, wherein the total thickness of the composite ceramic layer is 150-500 mu m;

and step 3: depositing a reflecting layer on the surface of the composite ceramic layer obtained in the step 2, wherein the thickness of the reflecting layer is 10-30 mu m;

and 4, step 4: depositing a catadioptric layer on the surface of the reflecting layer obtained in the step (3), wherein the thickness of the catadioptric layer is 10-30 mu m;

and 5: depositing an insulating layer on the surface of the catadioptric layer obtained in the step (4), wherein the thickness of the insulating layer is 10-200 mu m;

step 6: and (5) depositing a foam carbon layer on the surface of the insulating layer obtained in the step 5, wherein the thickness of the foam carbon layer is 20-200 mu m, so that the ultra-limit copper alloy is formed.

The beneficial effects of the technical scheme are as follows:

by controlling the thickness of each coating deposited on the copper alloy substrate, the service temperature of the prepared ultra-limit copper alloy can be increased to 100-500 ℃ higher than the melting point of the original copper alloy, and the prepared ultra-limit copper alloy has excellent corrosion resistance. Meanwhile, the situation that the weight of the prepared ultra-limit copper alloy is increased greatly due to the fact that the thickness of the coating is large can be avoided, and therefore the ultra-limit copper alloy can meet the use requirement of an aircraft.

Further, in the step 2, ZrO is formed to form the ceramic B layer₂-RETaO₄Is powder, the ZrO₂-RETaO₄The particle size of the powder is 10-70 mu m, and the shape of the powder is spherical.

Has the advantages that: ZrO with particle size of 10-70 mu m and spherical shape is adopted₂-RETaO₄The coating prepared from the powder is spherical, so that the surface of the powder is smooth, the powder has good fluidity, and a high-quality ceramic coating is obtained.

Further, in the step 1, before depositing the bonding layer, the surface of the copper alloy substrate is pretreated, wherein the pretreatment comprises degreasing and impurity removal; after the surface of the copper alloy matrix is pretreated, shot blasting is carried out on the surface of the copper alloy matrix, so that the surface roughness of the copper alloy matrix is 60-100 mu m.

Has the advantages that: the surface of the copper alloy substrate is degreased and decontaminated before the bonding layer is deposited, so that the oil stain and impurities can be prevented from entering the coating, the quality of the coating is influenced, and the problem that the coating is cracked or even falls off is avoided. The surface roughness of the copper alloy substrate can be improved by performing shot blasting on the surface of the copper alloy substrate, so that the bonding strength between the surface of the copper alloy substrate and the bonding layer is improved, and the probability of falling off of the bonding layer is reduced.

Drawings

FIG. 1 is a schematic structural view of an ultra-limited copper alloy according to the present invention;

FIG. 2 is a graph showing the high temperature creep test of example 1 and comparative example 13 under a stress of 50MPa and a temperature of 1300 ℃;

FIG. 3 is a graph of salt spray corrosion experiments for example 1 and comparative example 13 of the present invention.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: the light-emitting diode comprises a copper alloy substrate 1, a bonding layer 2, a precious metal layer 3, a ceramic A layer 4, a ceramic B layer 5, a reflecting layer 6, a catadioptric layer 7, an insulating layer 8 and a carbon foam layer 9.

The invention provides an ultra-limit copper alloy, which comprises a copper alloy substrate 1, wherein a composite bonding layer with the thickness of 100-200 mu m, a composite ceramic layer with the thickness of 150-500 mu m, a reflecting layer 6 with the thickness of 10-30 mu m, a catadioptric layer 7 with the thickness of 10-30 mu m, an insulating layer 8 with the thickness of 10-200 mu m and a foam carbon layer 9 with the thickness of 20-200 mu m are sequentially deposited on the surface of the copper alloy substrate 1 as shown in figure 1. Wherein the composite bonding layer is a bonding layer 2 deposited on the surface of the copper alloy matrix 1 and a noble metal layer 3 deposited on the surface of the bonding layer 2, the bonding layer 2 comprises one or a mixture of more of MCrAlY, NiAl, NiCr-Al and Mo alloy, and the MCrAlY is NiCrCoAlY and NiCoCrAlY, CoNiCrAlY or CoCrAlY; the component of the noble metal layer 3 is one or more of Au, Pt, Ru, Rh, Pd and Ir; the composite ceramic layer comprises a ceramic A layer 4 and a ceramic B layer 5, wherein the ceramic A layer 4 comprises YSZ or rare earth zirconate (RE)₂Zr₂O₇RE ═ Y, Gd, Nd, Sm, Eu, or Dy), the component of the ceramic B layer 5 is ZrO₂-RETaO₄(RE ═ Y, Gd, Nd, Sm, Eu, Dy, Er, Yb, or Lu); the reflecting layer 6 is REVO₄、RETaO₄、Y₂O₃Wherein RE is Y, Nd, Sm, Eu, Gd, Dy, Er, Yb or Lu. The component of the catadioptric layer 7 is one or a mixture of two of graphene and boron carbide, and the spatial distribution of the graphene and the boron carbide is in a disordered arrangement state; the insulating layer 8 is made of one or a mixture of epoxy resin, phenolic resin and ABS resin.

Wherein ZrO₂-RETaO₄The powder is prepared by the following method, which comprises the following steps:

step (1): ZrO 2 is mixed with₂Powder, rare earth oxide (RE)₂O₃) Powder, tantalum pentoxide (Ta)₂O₅) Pre-drying the powder at 600 ℃ for 8 h; according to ZrO₂-RETaO₄The dried ZrO was weighed in a molar ratio of₂Powder, rare earth oxide (RE)₂O₃) Powder, tantalum pentoxide (Ta)₂O₅) Powder; adding the pre-dried powder into an ethanol solvent to obtain a mixed solution, wherein the molar ratio of RE to Ta to Zr in the mixed solution is 1:1: 1; and then ball milling is carried out on the mixed solution for 10 hours by adopting a ball mill, and the rotating speed of the ball mill is 300 r/min.

Drying the slurry obtained after ball milling by using a rotary evaporator (model: N-1200B), wherein the drying temperature is 60 ℃, the drying time is 2h, and sieving the dried powder by using a 300-mesh sieve to obtain powder A.

Step (2): preparing ZrO from the powder A obtained in the step (1) by adopting a high-temperature solid-phase reaction method₂-RETaO₄The powder B of (1) is reacted at 1700 ℃ for 10 h; and the powder B was sieved using a 300 mesh sieve.

And (3): mixing the powder B sieved in the step (2) with a deionized water solvent and an organic adhesive to obtain slurry C, wherein the mass percent of the powder B in the slurry C is 25%, the mass percent of the organic adhesive is 2%, and the balance is the solvent, and the organic adhesive is polyvinyl alcohol or gum arabic; drying the slurry C by using a centrifugal atomization method at the temperature of 600 ℃ at the centrifugal speed of 8500r/min to obtain dried granules D;

and (4): sintering the material particles D obtained in the step (3) at 1200 ℃ for 8h, and sieving the sintered material particles D by using a 300-mesh sieve to obtain ZrO with particle size of 10-70 mu m and spherical appearance₂-RETaO₄Ceramic powder.

The invention utilizes ZrO₂-RETaO₄As the ceramic B layer, the ceramic B layer has the effects of low thermal conductivity and high expansion rate, and can reduce the heat conduction; and ZrO prepared by the above method₂-RETaO₄Can meet the requirements of APS spraying technology on the particle size and the shape of the powder.

The inventor finds out through a large number of experiments that the service temperature of the prepared ultra-limit copper alloy is increased to the maximum within the parameter range of the invention, the weight increase of the copper alloy is small, and the ultra-limit copper alloy with the optimal coating composition and thickness is provided, and 30 groups are listed for description in the invention.

The parameters of examples 1 to 30 of an ultra-limited copper alloy and a method for producing the same according to the present invention are shown in tables 1, 2 and 3:

TABLE 1 composition and thickness of each coating layer in examples 1-10 of an ultra-limiting copper alloy and a method for preparing the same

TABLE 2 composition and thickness of each coating layer in examples 11 to 20 of an ultra-limiting copper alloy and a method for preparing the same

TABLE 3 composition and thickness of each coating layer in examples 21 to 30 of an ultra-limiting copper alloy and a method for preparing the same

Now, a method for producing an ultra-limited copper alloy according to another embodiment of the present invention will be described with reference to example 1.

A preparation method of an ultra-limit copper alloy comprises the following steps:

step 1: the method comprises the steps of removing oil stains and impurities on the surface of a copper alloy matrix by using a soaking method, selecting C86100 copper alloy as a material of the copper alloy matrix in the embodiment, soaking the copper alloy matrix for 0.5-1.5 hours by using a solvent or an alkaline solution, wherein the main components of the solvent are ethanol and a surfactant, the main components of the alkaline solution are sodium hydroxide, trisodium phosphate, sodium carbonate, sodium silicate and the like, the pH value of the alkaline solution is 10-11, cleaning the surface of the copper alloy matrix by using the solvent in the embodiment, taking out the copper alloy matrix after cleaning the oil stains and the impurities, washing the copper alloy matrix by using deionized water, and drying the copper alloy matrix.

Shot blasting is carried out on the surface of the copper alloy substrate by using a shot blasting machine, the used shot blasting machine is a JCK-SS500-6A automatic transmission type shot blasting machine, the shot blasting material adopted in shot blasting is any one of iron sand, glass shot and ceramic shot, the iron sand is used in the embodiment, the particle size of the iron sand is 0.3-0.8mm, and the particle size of the iron sand is 0.5mm in the embodiment; the surface roughness of the copper alloy matrix after shot blasting is 60-100 μm, and the surface roughness of the copper alloy matrix in the embodiment is 80 μm, so that the coating and the copper alloy matrix can be conveniently bonded.

Step 2: depositing a composite bonding layer on the surface of the copper alloy matrix after shot blasting, firstly spraying a NiCrCoAlY layer on the surface of the copper alloy matrix by using an HVOF method (supersonic flame spraying method) or a supersonic electric arc spraying method as the bonding layer, wherein the HVOF method is used in the embodiment, and the HVOF method has the process parameters as follows: the powder particle diameter was 25-65 μm, the oxygen flow rate was 2000SCFH, the kerosene flow rate was 18.17LPH, the carrier gas was 12.2SCFH, the powder feed rate was 5RPM, the barrel length was 5in, and the spray distance was 254 mm.

And then, a layer of Au is deposited on the NiCrCoAlY bonding layer by using an EB-PVD method (an electron beam physical vapor deposition method) to serve as a noble metal layer, so that the composite bonding layer is formed. The gas pressure when depositing Au is less than 0.01Pa, and the technological parameters of the EB-PVD method are as follows: the pressure is 0.008Pa, the deposition rate is 6nm/min, and the ratio of the temperature of the copper alloy matrix to the melting point of the copper alloy matrix is less than 0.3. The thickness of the deposited bonding layer was 45 μm and the thickness of the noble metal layer was 45 μm.

And step 3: spraying a layer of YSZ on the surface of the composite bonding layer by APS (atmospheric plasma spraying), HVOF, PS-PVD or EB-PVD method to serve as a ceramic A layerIn the examples, HVOF method is used, and then HVOF method is used to spray a layer of ZrO on YSZ ceramic A layer₂-YTaO4 as a ceramic B layer forming a composite ceramic layer, the process parameters of the HVOF process being the same as in step 2; wherein the thickness of the ceramic A layer is 70 μm and the thickness of the ceramic B layer is 50 μm.

And 4, step 4: spraying a layer of Y on the surface of the composite ceramic layer by using HVOF method₂O₃The transparent ceramic material is used as a reflecting layer, and the thickness of the sprayed reflecting layer is 20 mu m.

And 5: by applying a brush on Y₂O₃The surface of the reflecting layer is coated with a layer of graphene as a catadioptric layer, and the thickness of the catadioptric layer is 10 mu m.

The graphene has a high specific surface area and is extremely difficult to dissolve in a solution, so that the graphene needs to be subjected to ultrasonic dispersion and solid-liquid separation before coating, namely, the graphene and a micron-sized carbon powder material are uniformly mixed, then mixed powder is introduced into the solution to be subjected to ultrasonic vibration mixing, the solution in the embodiment is an ethanol solution added with 1% of a dispersing agent, the micron-sized carbon powder is separated from the uniformly mixed solution by using filter paper, finally the solution mixed with the graphene is coated on the surface of a reflecting layer, and then the copper alloy coated with a graphene catadioptric layer is placed into a drying box and dried for 2 hours at the temperature of 60 ℃.

In addition, after the graphene is subjected to ultrasonic dispersion, the spatial distribution of the graphene is rearranged in all directions, so that the spatial distribution of the graphene is in a disordered arrangement state, the graphene has a higher refractive index, when incident light irradiates on a graphene catadioptric layer, the refraction of light in all directions can be enhanced by the disordered arranged graphene, the incident light is prevented from being refracted in the same direction, the effect of refraction dispersion is achieved, and the incident light intensity entering the coating is reduced.

Step 6: and (3) coating a layer of epoxy resin as an insulating layer on the surface of the graphene catadioptric layer by using a coating method, wherein the thickness of the insulating layer is 15 microns.

And 7: a carbon foam layer was coated on the epoxy resin insulation layer by a brushing method, and the carbon foam layer had a thickness of 20 μm.

Examples 2-29 were prepared in the same manner as example 1, except that the composition and thickness of each coating layer was different as shown in table 1; example 30 differs from example 1 in the spraying sequence of the ceramic a layer and the ceramic B layer in step 3.

In addition, 13 sets of comparative experiments were carried out on the comparative examples and examples 1 to 30.

Table 4 shows the composition and thickness of each coating of comparative examples 1-12:

comparative examples 1 to 12 were the same as in example 1 except that the composition and thickness of each coating layer were different as shown in table 3, and comparative example 13 was a C86100 copper alloy matrix on which no coating layer was deposited.

The following experiments were carried out using the copper alloys provided in examples 1 to 30 and comparative examples 1 to 13:

1. high temperature creep test:

the copper alloys prepared in examples 1 to 30 and comparative examples 1 to 13 were processed into tensile test pieces, and a high-temperature creep test was performed using an electronic high-temperature creep rupture strength tester of type RMT-D5, wherein the maximum test load was 50KN, the test load control accuracy was within. + -. 5%, the deformation measurement range was 0 to 10mm, and the rate adjustment range was 0 to 50mm/min^-1The deformation resolution is 0.001mm, the temperature control range of the high-temperature furnace is 200-2000 ℃, and the length of the soaking zone is 150 mm.

The test pieces of examples 1 to 30 and comparative examples 1 to 13 were placed in an electronic high temperature creep rupture strength tester and the test pieces were left in an unstressed state (in the unstressed state, the test pieces were free to expand, and high temperature creep is deformation that increases with time under the combined action of temperature and stress, so that the rate of temperature rise had no effect on creep). The tester was adjusted to a stress of 50MPa and a temperature of 1300 ℃, and the following data was recorded, as shown in table 5, wherein a in table 5 represents the steady creep time (min) of each test piece; b represents the time (min) for creep rupture of each test piece.

Taking example 1 and comparative example 13 as examples, as shown in fig. 2, the high temperature creep test graphs of example 1 and comparative example 13 are shown, wherein (a) in fig. 2 shows a C86100 copper alloy base material without a deposited coating in comparative example 13, and (B) in fig. 2 shows the material prepared in example 1.

As can be seen from FIG. 2, there are 3 stages of creep of the test pieces (A) and (B) at a temperature of 1300 ℃ under a stress of 50 MPa: the first stage is short and has a large creep rate, and the first stage is quickly transited to a creep second stage, wherein the creep rate of the second stage reaches a minimum value, and the second stage is long and is basically in a steady-state creep process; in the third stage, the creep rate is rapidly increased, and creep deformation rapidly develops until the material is damaged and creep fracture occurs. Under the stress of 50MPa and the temperature condition of 1300 ℃, the test piece (A) is cracked in a very short time, which shows that the copper alloy can hardly bear load under the temperature condition of being higher than the melting point, while the test piece (B) can keep good mechanical property for a long time without cracking under the condition of 1300 ℃ and has excellent high-temperature resistance.

2. Salt spray corrosion test:

the copper alloys provided in examples 1 to 30 and comparative examples 1 to 13 were processed into 50mm × 25mm × 2mm test pieces, subjected to oil and rust removal treatment, and cleaned and dried. An YWX/Q-250B salt spray corrosion box is used as experimental equipment, and an atmospheric corrosion environment of GB/T2967.3-2008 is simulated.

The test pieces provided in examples 1 to 30 and comparative examples 1 to 13 were hung in a test apparatus, the temperature of the test apparatus was adjusted to 50 ± 1 ℃ and the PH was adjusted to 3.0 to 3.1, the test pieces were continuously sprayed with a NaCl solution having a concentration of 5 ± 0.5%, and the weight loss ratios of the respective test pieces were recorded in table 5 after a certain time (8, 24, 48, 72 hours).

As shown in FIG. 3, the weight loss by salt spray corrosion is plotted against corrosion time for examples 1 and comparative examples 13, wherein (A) in FIG. 3 represents the C86100 copper alloy base material without the deposited coating in comparative example 13, and (B) in FIG. 3 represents the material prepared in example 1.

From FIG. 3Therefore, the two copper alloys have obviously different corrosion laws, and the corrosion weight loss value of the test piece (A) (C86100 copper alloy test piece) tends to increase along with the prolonging of the corrosion time. In the initial stage of corrosion (8-24h), an oxide film exists on the surface of the sample, so that the contact between a copper alloy matrix and a solution is prevented, and the corrosion rate is low. In the middle stage of corrosion (24-48h), Cl in the solution^-(chloride ion) has penetrated the oxide film and a large amount of Cl^-The corrosion inhibitor is adsorbed on a substrate, so that pitting pits are increased, original pitting pits are deepened, and the corrosion rate is obviously accelerated. After 48h of continuous spraying, the corrosion products were distributed uniformly and increased in thickness, covering almost the entire surface of the test specimen, with Cl^-Needs to penetrate through corrosion products to be contacted with the copper alloy substrate, thereby reducing the Cl adsorbed on the surface of the substrate^-In such an amount that the corrosion rate is reduced. In general, the corrosion weight loss of the C86100 copper alloy is much higher than that of the copper-based surface composite material, the copper-based surface composite material is basically not corroded due to the existence of the coating, and the quality of the copper-based surface composite material is hardly changed.

In table 5, a represents the steady creep time (min) of each test piece; b represents the time (min) for creep rupture of each test piece;

c represents the weight loss rate (v/mg. cm) of the test piece after the NaCl solution is continuously sprayed on the test piece for 8 hours²)；

d represents the weight loss rate (v/mg. cm) of the test piece after spraying NaCl solution to the test piece for 24 hours continuously²)；

e represents the weight loss rate (v/mg. cm) of the test piece after spraying NaCl solution to the test piece for 48 hours continuously²)；

f represents the weight loss rate (v/mg. cm) of the test piece after the NaCl solution is continuously sprayed on the test piece for 72 hours²)。

Table 5 shows the results of the high temperature creep test and the salt spray test

As can be seen from table 5, the copper alloy obtained in the comparative example, which is out of the parameter range of the present invention, has a greatly reduced stability at high temperature, is fractured in a short time, and has poor corrosion resistance.

In conclusion, the anti-oxidation composite bonding layer, the composite ceramic layer, the reflecting layer, the catadioptric layer, the insulating layer and the foam carbon layer are deposited on the copper alloy, so that the use temperature of the copper alloy can be increased to be higher than 100-500 ℃ of the original melting point, and the corrosion resistance is greatly improved. The ultra-limit copper alloy prepared by the preparation method of the ultra-limit copper alloy provided by the invention has the advantages of wide use temperature range and strong corrosion resistance, wherein each effect of the embodiment 1 is the best.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. An ultra-limit copper alloy comprising a copper alloy matrix, characterized in that: a composite bonding layer and a composite ceramic layer are sequentially deposited on the surface of the copper alloy substrate; the composite bonding layer comprises a bonding layer deposited on the surface of the copper alloy substrate and a noble metal layer deposited on the surface of the bonding layer; the composite ceramic layer comprises a ceramic layer A and a ceramic layer B; a reflecting layer, a catadioptric layer, an insulating layer and a foam carbon layer are sequentially deposited outside the composite ceramic layer, the thickness of the composite bonding layer is 100-200 mu m, the thickness of the composite ceramic layer is 150-500 mu m, the thickness of the reflecting layer is 10-30 mu m, the thickness of the catadioptric layer is 10-30 mu m, the thickness of the insulating layer is 10-200 mu m and the thickness of the foam carbon layer is 20-200 mu m; the bonding layer is one or a mixture of more of MCrAlY, NiAl, NiCr-Al and Mo alloy, and the MCrAlY is NiCrCoAlY, NiCoCrAlY, CoNiCrAlY or CoCrAlY; the components of the noble metal layer are Au, Pt, Ru,An alloy of one or more of Rh, Pd, Ir; the ceramic layer A contains YSZ or rare earth zirconate (RE)₂Zr₂O₇) The component of the ceramic B layer is ZrO₂-RETaO₄(ii) a The composition of the reflecting layer is REVO₄、RETaO₄、Y₂O₃One or a mixture of several of them; the component of the catadioptric layer is one or a mixture of two of graphene or boron carbide, and the spatial distribution of the graphene and the boron carbide is in a disordered arrangement state; the insulating layer is composed of one or a mixture of more of epoxy resin, phenolic resin and ABS resin.

2. The method of claim 1, comprising the steps of:

step 1: depositing a bonding layer on the surface of the copper alloy substrate by using an HVOF method; depositing a noble metal layer on the surface of the bonding layer by using an EB-PVD method so that the bonding layer and the noble metal layer form a composite bonding layer, wherein the total thickness of the composite bonding layer is 100-200 mu m;

step 2: depositing a ceramic layer A and a ceramic layer B on the surface of the composite bonding layer obtained in the step 1 by using an HVOF method, so that the ceramic layer A and the ceramic layer B form a composite ceramic layer, and the total thickness of the composite ceramic layer is 150-500 mu m;

and step 3: depositing a reflecting layer on the surface of the composite ceramic layer obtained in the step 2 by using an HVOF method, wherein the thickness of the reflecting layer is 10-30 mu m;

and 4, step 4: depositing a catadioptric layer on the surface of the reflecting layer obtained in the step (3) by using a painting method, wherein the thickness of the catadioptric layer is 10-30 mu m;

and 5: depositing an insulating layer on the surface of the catadioptric layer obtained in the step (4) by using a brushing method, wherein the thickness of the insulating layer is 10-200 mu m;

step 6: and (5) depositing a foam carbon layer on the surface of the insulating layer obtained in the step (5) by using a brushing method, wherein the thickness of the foam carbon layer is 20-200 mu m, so that the ultra-limit copper alloy is formed.

3. The method of claim 2, wherein the step of preparing the ultra-limited copper alloy comprises: the steps areIn step 2, ZrO of ceramic B layer is formed₂-RETaO₄Is powder, the ZrO₂-RETaO₄The particle size of the powder is 10-70 mu m, and the shape of the powder is spherical.

4. The method of claim 3, wherein the step of preparing the ultra-limited copper alloy comprises: in the step 1, before depositing the bonding layer, the surface of the copper alloy substrate is pretreated, wherein the pretreatment comprises degreasing and impurity removal; after the surface of the copper alloy matrix is pretreated, shot blasting is carried out on the surface of the copper alloy matrix, so that the surface roughness of the copper alloy matrix is 60-100 mu m.