CN109609953B - Ultra-limit copper alloy and preparation method thereof - Google Patents

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. The invention comprises a copper alloy substrate, and a composite bonding layer, a composite ceramic layer, a reflection layer and an antireflection layer are sequentially deposited on the surface of the copper alloy substrate. , insulating layer and carbon foam layer; the composite bonding layer includes the bonding layer deposited on the surface of the copper alloy substrate and the precious metal layer deposited on the surface of the bonding layer; the composite ceramic layer includes the ceramic A layer and the ceramic B layer. By depositing a multi-layer coating on the surface of the copper alloy base, the present invention can raise its use temperature to 100-500°C higher than the melting point of the original copper alloy base, so as to realize the use of the copper alloy in an ultra-limited environment. The ultra-limit copper alloy provided by the invention has excellent high-temperature mechanical and chemical stability, and can be used under the conditions exceeding the melting point of the copper alloy matrix, thereby increasing the use range.

Description

A kind of ultra-limit copper alloy and preparation method thereof

technical field

The invention belongs to the technical field of copper alloy material preparation, in particular to an ultra-limit copper alloy and a preparation method thereof.

Background technique

As an important metal material today, copper alloy refers to an alloy composed of copper as the matrix and other elements added. Copper has good mechanical, physical and chemical properties, and copper alloys formed by adding suitable elements to copper have strong oxidation resistance, corrosion resistance, high temperature strength, and can improve some physical properties, so copper alloys are widely used in energy. Development, chemical, electronic, marine, aviation and aerospace fields. Copper alloys have played an irreplaceable role in the aerospace field due to their strong comprehensive properties such as strength, hardness, shock resistance, corrosion resistance, oxidation resistance, high temperature strength and certain physical properties. For example, the lining of the combustion chamber and thrust chamber of a rocket engine can be cooled by the excellent thermal conductivity of copper to ensure that the temperature of the engine is within the allowable range. The combustion chamber lining of the Arizona 5 rocket is made of copper-silver alloy. 360 cooling channels are machined in this lining, and liquid hydrogen is introduced into the rocket for cooling.

With the development of technology and the actual needs of society, the speed requirements for aircraft are also getting higher and higher. The increase in the speed of the aircraft means that the operating speed of the engine gradually increases, which leads to the gradual increase of the surface temperature of the engine blades. Although copper alloys have many It has excellent performance, but its melting point is around 1080°C and its easy oxidation at high temperature greatly limits the use of copper alloys under high temperature conditions. In addition, when the metal works at a temperature exceeding half of its melting point, the phenomenon of softening will occur, that is, when the copper alloy works in an environment of 540 °C, it will soften and reduce its performance. However, the current copper alloys cannot meet the requirements for the use of aircraft after speed-up (that is, copper alloys cannot be used at ultra-limit temperature (exceeding the melting point temperature of copper alloys)), or in order to achieve the requirements of aircraft speed-up, the use of aircraft must be sacrificed. life. Therefore, the development of aircraft, and even the development of copper alloys as a whole has been limited, and the use of copper alloys has been limited, reaching a bottleneck.

SUMMARY OF THE INVENTION

The present invention is intended to provide an ultra-limit copper alloy and a preparation method thereof, so as to solve the problem that the existing copper alloy cannot meet the use at the ultra-limit temperature.

For achieving the above object, the present invention provides following basic scheme:

An ultra-limit copper alloy, comprising a copper alloy base, a composite bonding layer and a composite ceramic layer are sequentially deposited on the surface of the copper alloy base; the composite bonding layer comprises the bonding layer deposited on the surface of the copper alloy base and the bonding layer deposited on the The precious metal layer on the surface of the layer; the composite ceramic layer includes a ceramic A layer and a ceramic B layer.

The beneficial effects of this technical solution:

Through a lot of research, the inventor has developed an ultra-limited copper alloy, which satisfies the use of the copper alloy at the ultra-limited temperature (exceeding its melting temperature). In the process of research and development, people usually think that when the ambient temperature is higher than the use temperature of the alloy, it will be considered that the alloy cannot be used at this temperature, and other alloys with high melting point are required for use, and the inventor does the opposite. OK, try to improve copper alloys to meet the needs of aircraft manufacturing. In the process of continuous attempts, the inventor found that by depositing a certain proportion of coating on the surface of the copper alloy, the service temperature of the copper alloy can be increased to 100-500°C higher than the original melting point, which will greatly improve the use of the copper alloy. Therefore, it is very difficult to increase the use temperature of copper alloys by 2-3 °C in a high temperature environment, so the applicant's research is a very big progress in the use of copper alloys .

By depositing the composite bonding layer and the composite ceramic layer on the copper alloy substrate, the technical solution can greatly improve the service temperature of the copper alloy, so as to adapt to the use of the copper alloy under the condition of ultra-limit temperature. Deposition of the composite bonding layer can improve the bonding effect between each coating and the copper alloy substrate, and prevent the coating from falling off during use. Depositing a composite ceramic layer can reduce heat conduction, thereby increasing the service temperature of the copper alloy substrate. In this technical solution, the use temperature of the copper alloy is greatly improved through the cooperation of various coatings.

To sum up, the present invention has the following technical effects:

1. The ultra-limit copper alloy provided by the present invention has excellent high-temperature mechanical and chemical stability, and can be used under the conditions exceeding the melting point of the copper alloy matrix, thereby increasing the scope of use.

2. In the present invention, by depositing a multi-layer coating on the surface of the copper alloy base, the service temperature can be raised to 100-500°C higher than the melting point of the original copper alloy base, so as to realize the use of the copper alloy in an ultra-limited environment.

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

4. The ultra-limit copper alloy provided by the present invention breaks through the development bottleneck of traditional copper alloys, and can further increase its service temperature on the basis of its higher melting point, and the increased temperature is a leap forward. The ultra-limit copper alloy provided by the invention can be applied to the preparation of the engine blade of the aircraft, and can meet the use requirement of the temperature increase of the engine when the aircraft is accelerated, and realize the acceleration of the aircraft.

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 10-30 μm thick reflective layer, a 10-30 μm thick antireflection layer, 10-200μm thick insulating layer and 20-200μm thick foam carbon layer.

Beneficial effects: the reflective layer has the effect of reflecting the heat source, thereby reducing the heat source on the surface of the copper alloy, thereby increasing the use temperature. Deposition of the anti-refractive layer can block the refraction of infrared rays in the coating layer, thereby reducing the temperature of the copper alloy substrate, thereby increasing the service temperature of the prepared copper alloy. The effect of depositing the insulating layer is that in the ultra-high-speed environment, the surface of the material is prone to ionization, and the insulating layer can isolate the conductive ions or electrons generated by the ionization from entering the copper alloy matrix, thereby resisting the corrosion of the copper alloy matrix by charges. . During use, the carbon of the foamed carbon layer vaporizes and cools down, and a vaporized film is formed on the surface of the copper alloy substrate, which further prevents heat transfer, thereby increasing the service temperature of the copper alloy. And by setting the thickness of each coating, the use temperature of the prepared ultra-limit copper alloy can be increased, and the weight of the coating can be controlled while ensuring the thermal insulation effect of the coating, which is convenient for the use of aircraft.

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

Beneficial effects: In the three materials NiCrCoAlY, NiCoCrAlY and CoNiCrAlY, the content of each element decreases in turn according to the chemical formula, and the proportions of each element in the three materials are different, so the prepared materials are different. The bonding layer has a good bonding effect, so that the subsequent coating has a good bonding effect with the copper alloy substrate and reduces the probability of the coating falling off; and the precious metal itself has anti-oxidation properties, which can effectively prevent the oxidation of oxygen at high temperatures. It diffuses into the bonding layer and the copper alloy matrix, thereby improving the oxidation resistance of the coating and prolonging the life of the coating.

Further, the composition of the ceramic A layer is YSZ or rare earth zirconate (RE ₂ Zr ₂ O ₇ ), and the composition of the ceramic B layer is ZrO ₂ -RETaO ₄ .

Beneficial effects: YSZ or rare earth zirconate is the most commonly used component of the ceramic layer in the thermal barrier coating at present, and the preparation process is mature and convenient to buy; while ZrO ₂ -RETaO ₄ has the effect of high expansion coefficient and low thermal conductivity, among which low thermal conductivity Conductivity can reduce the conduction of external heat into the copper alloy matrix, so that the copper alloy matrix can maintain a lower temperature in a high temperature environment; and for high expansion coefficients, since the coatings are used as a whole, not a single The high expansion coefficient is in order to match the thermal expansion coefficient of the bonding layer. Since the thermal expansion coefficient of the precious metal bonding layer is also large, in the process of thermal cycling (that is, during the continuous heating and cooling process), the ceramic The thermal mismatch stress (stress caused by different thermal expansion coefficients) between the layer and the bonding layer is small, thereby increasing the service life of the coating. (In layman's terms, when two coatings with a large difference in thermal expansion coefficient are deposited together, when the temperature increases or decreases, the expansion degrees of the two coatings are seriously different, which will lead to an increase in the stress between the two coatings. This leads to the problem of cracks or even peeling between the two coatings.)

Further, the composition of the reflective layer is one or a mixture of REVO ₄ , RETaO ₄ and Y ₂ O ₃ .

Beneficial effects: REVO4, RETaO4, Y2O3 have high reflection coefficients, so the reflection effect on thermal radiation is good, greatly reducing the temperature of the copper alloy substrate in a high temperature environment, thereby increasing the use temperature of the prepared copper alloy.

Further, the composition of the antireflection layer is one or a mixture of graphene and boron carbide, and the spatial distribution of graphene and boron carbide is in a disordered state.

Beneficial effect: Since the spatial distribution of graphene or boron carbide is in a disordered state, although graphene or boron carbide has a higher refractive index, when infrared light is irradiated on the graphene antireflection layer, the disordered arrangement Graphene can enhance the refraction of light in all directions, avoid the refraction of incident light in the same direction, and achieve the effect of refraction dispersion, so that the intensity of infrared light entering the coating decreases, thereby reducing the temperature of the coating and the copper alloy substrate .

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

Beneficial effects: Take an aircraft as an example. During high-speed flight, the outer surface of the aircraft rubs against the air, causing the air to be ionized to form conductive ions or electrons. The coating can effectively resist the charge into the coating and the copper alloy matrix, thereby reducing the erosion of the tin alloy weld by conductive electrons or ions.

The present invention also provides another technical solution, a preparation method of ultra-limit copper alloy, comprising the following steps:

Step 1: depositing a bonding layer on the surface of the copper alloy substrate; depositing a precious metal layer on the surface of the bonding layer, so that the bonding layer and the precious metal layer form a composite bonding layer, and the total thickness of the composite bonding layer is 100-200 μm;

Step 2: depositing the ceramic A layer and the ceramic B layer on the surface of the composite bonding layer obtained in the step 1, so that the ceramic A layer and the ceramic B layer form a composite ceramic layer, and the total thickness of the composite ceramic layer is 150-500 μm;

Step 3: deposit a reflective layer on the surface of the composite ceramic layer obtained in step 2, and the thickness of the reflective layer is 10-30 μm;

Step 4: deposit a catadioptric layer on the surface of the reflective layer obtained in step 3, and the thickness of the catadioptric layer is 10-30 μm;

Step 5: deposit an insulating layer on the surface of the antireflection layer obtained in step 4, and the thickness of the insulating layer is 10-200 μm;

Step 6: deposit a carbon foam layer on the surface of the insulating layer obtained in step 5, and the thickness of the carbon foam layer is 20-200 μm, thereby forming an ultra-limit copper alloy.

The beneficial effects of this technical solution:

By controlling the thickness of each coating deposited on the copper alloy substrate, the use temperature of the prepared ultra-limit copper alloy can be increased to 100-500°C higher than the melting point of the original copper alloy, and it has excellent corrosion resistance. . At the same time, it can also avoid the situation that the weight of the prepared ultra-limit copper alloy increases greatly due to the larger coating thickness, so that the ultra-limit copper alloy can meet the use of aircraft.

Further, in the step 2, the ZrO _{2 -RETaO 4 powder is used to form the ceramic B layer, and the ZrO 2 -RETaO 4 powder has} a particle size of 10-70 μm and a spherical shape.

Beneficial effects: The coating is prepared by using ZrO ₂ -RETaO ₄ powder with a particle size of 10-70 μm and a spherical shape. Because the powder is spherical, the surface of the powder is smooth and the fluidity of the powder is better. , a high-quality ceramic coating was obtained.

Further, in the step 1, before depositing the bonding layer, the surface of the copper alloy substrate is pretreated, and the pretreatment includes degreasing and impurity removal; after the surface pretreatment of the copper alloy substrate, the surface of the copper alloy substrate is pretreated. The surface is shot peened so that the surface roughness of the copper alloy substrate is 60-100 μm.

Beneficial effects: Degreasing and removing impurities on the surface of the copper alloy substrate before depositing the bonding layer can prevent oil and impurities from entering the coating, thereby affecting the quality of the coating, thereby avoiding the problem of cracking or even falling off of the coating . The surface roughness of the copper alloy substrate can be improved by shot peening on the surface of the copper alloy substrate, thereby improving the bonding strength between the surface of the copper alloy substrate and the bonding layer, and reducing the probability of the bonding layer falling off.

Description of drawings

Fig. 1 is the structural representation of a kind of ultra-limit copper alloy of the present invention;

Fig. 2 is the experimental curve diagram of high temperature creep under 50MPa stress and 1300°C temperature of Example 1 and Comparative Example 13 of the present invention;

FIG. 3 is a graph of salt spray corrosion experiments of Example 1 and Comparative Example 13 of the present invention.

Detailed ways

The following is further described in detail by specific embodiments:

Reference numerals in the accompanying drawings include: copper alloy substrate 1, adhesive layer 2, precious metal layer 3, ceramic A layer 4, ceramic B layer 5, reflective layer 6, antireflection layer 7, insulating layer 8, foam carbon layer 9.

The present invention provides an ultra-limit copper alloy, as shown in FIG. 1 , comprising a copper alloy substrate 1, and the surface of the copper alloy substrate 1 is sequentially deposited with a composite bonding layer with a thickness of 100-200 μm, and a composite ceramic with a thickness of 150-500 μm. layers, a reflective layer 6 with a thickness of 10-30 μm, a retroreflection layer 7 with a thickness of 10-30 μm, an insulating layer 8 with a thickness of 10-200 μm and a foamed carbon layer 9 with a thickness of 20-200 μm. The composite bonding layer is the bonding layer 2 deposited on the surface of the copper alloy substrate 1 and the precious metal layer 3 deposited on the surface of the bonding layer 2. The composition of the bonding layer 2 is MCrAlY, NiAl, NiCr-Al, Mo alloys. One or more mixtures, MCrAlY is NiCrCoAlY, NiCoCrAlY, CoNiCrAlY or CoCrAlY; the composition of noble metal layer 3 is one or more alloys in Au, Pt, Ru, Rh, Pd, Ir; the composite ceramic layer includes deposition In the ceramic A layer 4 and the ceramic B layer 5, the composition of the ceramic A layer 4 is YSZ or rare earth zirconate (RE ₂ Zr ₂ O ₇ , RE=Y, Gd, Nd, Sm, Eu or Dy), and the ceramic B layer is The composition of 5 is ZrO ₂ -RETaO ₄ (RE=Y, Gd, Nd, Sm, Eu, Dy, Er, Yb or Lu); the reflective layer 6 is one of REVO ₄ , RETaO ₄ , Y ₂ O ₃ or Mixtures of several where RE=Y, Nd, Sm, Eu, Gd, Dy, Er, Yb or Lu. The composition of the antireflection layer 7 is a mixture of one or both of graphene and boron carbide, and the spatial distribution of graphene and boron carbide is in a disordered state; the composition of the insulating layer 8 is epoxy resin, phenolic resin , One or more mixtures of ABS resin.

The ZrO ₂ -RETaO ₄ powder is prepared by the following method, including the following steps:

Step (1): pre-drying ZrO ₂ powder, rare earth oxide (RE ₂ O ₃ ) powder, and tantalum pentoxide (Ta ₂ O ₅ ) powder, the pre-drying temperature is 600° C., and the pre-drying time is 8h ; Weigh the dried ZrO ₂ powder, rare earth oxide (RE ₂ O ₃ ) powder, and tantalum pentoxide (Ta ₂ O ₅ ) powder according to the molar ratio of ZrO ₂ -RETaO ₄ ; add the pre-dried powder to the In an ethanol solvent, a mixed solution is obtained, so that the molar ratio of RE:Ta:Zr in the mixed solution is 1:1:1; the mixed solution is then ball-milled for 10 hours by a ball mill, and the rotational speed of the ball mill is 300 r/min.

The slurry obtained after ball milling was dried with a rotary evaporator (model: N-1200B) at a drying temperature of 60° C. and a drying time of 2 hours. The dried powder was sieved with a 300-mesh sieve to obtain powder A.

Step (2): The powder A obtained in the step (1) is prepared by a high-temperature solid-phase reaction method to obtain a powder B with the composition ZrO ₂ -RETaO ₄ , the reaction temperature is 1700 ° C, and the reaction time is 10 h; and a 300-mesh sieve is used to Powder B is sieved.

Step (3): Mix the sieved powder B in step (2) with a deionized water solvent and an organic binder to obtain a slurry C, wherein the mass percentage of the powder B in the slurry C is 25%, and the organic bonding The mass percentage of the agent is 2%, the rest is solvent, and the organic binder is polyvinyl alcohol or gum arabic; and then the slurry C is dried by centrifugal atomization, the drying temperature is 600 ℃, and the centrifugal speed is 8500r /min, to obtain dry pellets D;

Step (4): sintering the particles D obtained in step (3) at a temperature of 1200° C. for 8 hours, and then sieving the sintered particles D with a 300-mesh sieve to obtain a particle size of 10-70 μm and a shape of 10 μm. Spherical ZrO ₂ -RETaO ₄ ceramic powder.

The present invention uses ZrO ₂ -RETaO ₄ as the ceramic B layer, which has the effects of low thermal conductivity and high expansion rate, and can reduce heat conduction; and the ZrO ₂ -RETaO ₄ prepared by the above method can meet the requirements of APS spraying technology for powder Particle size and morphology requirements.

The inventor has obtained through a large number of experiments that within the parameter range of the present invention, the use temperature of the prepared ultra-limit copper alloy is the largest, and the weight increase of the copper alloy is small, and the ultra-limit copper with the best composition and thickness of each coating layer. Alloys, and 30 groups of which are listed in the present invention are described.

The parameters of Examples 1-30 of an ultra-limit copper alloy of the present invention and its preparation method are shown in Table 1, Table 2, and Table 3:

Table 1 Composition and thickness of each coating in Examples 1-10 of an ultra-limit copper alloy and its preparation method

The composition and thickness of each coating in the embodiment 11-20 of table 2 a kind of ultra-limit copper alloy and preparation method thereof

The composition and thickness of each coating in the embodiment 21-30 of table 3 a kind of ultra-limit copper alloy and preparation method thereof

Taking Example 1 as an example, another technical solution of the present invention, a method for preparing an ultra-limit copper alloy, will be described.

A preparation method of ultra-limit copper alloy, comprising the following steps:

Step 1: Use the immersion method to remove oil stains and impurities on the surface of the copper alloy substrate. In this embodiment, the material of the copper alloy substrate is C86100 copper alloy, and the copper alloy substrate is soaked in a solvent or an alkaline solution for 0.5 to 1.5 hours, wherein the main components of the solvent are It is ethanol and surfactant. The main components of the alkaline solution are sodium hydroxide, trisodium phosphate, sodium carbonate, sodium silicate, etc. The pH value of the alkaline solution is 10 to 11. In this embodiment, a solvent is used to clean the surface of the copper alloy substrate. , after cleaning the oil and impurities, take out the copper alloy substrate, rinse it with deionized water, and then dry it.

The surface of the copper alloy substrate is then shot peened by a shot peening machine. The shot peening machine used is a JCK-SS500-6A automatic transmission shot peening machine. The shot peening materials used in the shot peening are iron sand, glass shot and ceramic shot. Any one, iron sand is used in this embodiment, and the particle size of iron sand is 0.3-0.8mm, and the particle size of iron sand in this embodiment is 0.5mm; the surface roughness of the copper alloy substrate after shot peening is 60-100μm, this In the examples, the surface roughness of the copper alloy substrate is 80 μm, which facilitates the bonding between the coating and the copper alloy substrate.

Step 2: deposit a composite bonding layer on the surface of the copper alloy substrate after shot peening. First, use the HVOF method (supersonic flame spraying method) or supersonic arc spraying method to spray a layer of NiCrCoAlY on the surface of the copper alloy substrate as the bonding layer, In this example, the HVOF method is used. The process parameters of the HVOF method are: the powder particle size is 25-65 μm, the oxygen flow rate is 2000SCFH, the kerosene flow rate is 18.17LPH, the carrier gas is 12.2SCFH, the powder feeding rate is 5RPM, and the barrel length is 5in , The spraying distance is 254mm.

Then, a layer of Au is deposited on the NiCrCoAlY bonding layer as a precious metal layer by EB-PVD method (electron beam physical vapor deposition method) to form a composite bonding layer. The gas pressure when depositing Au is less than 0.01Pa, the process parameters of EB-PVD method are: pressure 0.008Pa, deposition rate 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 tie layer was 45 μm and the thickness of the precious metal layer was 45 μm.

Step 3: Use APS (atmospheric plasma spraying), HVOF, PS-PVD or EB-PVD method to spray a layer of YSZ on the surface of the composite bonding layer as a ceramic A layer. A layer of ZrO ₂ -YTaO4 is sprayed on the YSZ ceramic A layer as the ceramic B layer to form a composite ceramic layer. The process parameters of the HVOF method are the same as those in step 2; the thickness of the ceramic A layer is 70 μm, and the thickness of the ceramic B layer is 50 μm .

Step 4: Spray a layer of Y ₂ O ₃ transparent ceramic material on the surface of the composite ceramic layer by HVOF method as a reflection layer, and the thickness of the sprayed reflection layer is 20 μm.

Step 5: Use a brushing method to paint a layer of graphene on the surface of the Y ₂ O ₃ reflective layer as a retroreflection layer, and the thickness of the antireflection layer is 10 μm.

Because graphene has a high specific surface area and is extremely insoluble in solution, graphene needs to be ultrasonically dispersed and solid-liquid separated before coating. The mixed powder is introduced into the solution for ultrasonic vibration mixing. In this embodiment, the solution is an ethanol solution with 1% dispersant added. After the solution is evenly mixed, filter paper is used to separate the micron-scale carbon powder, and finally the graphene is mixed with it. The solution was coated on the surface of the reflective layer, and then the copper alloy coated with the graphene antireflection layer was placed in a drying oven and dried at 60 °C for 2 h.

In addition, after graphene is ultrasonically dispersed, the spatial distribution of graphene is rearranged in all directions, so that the spatial distribution of graphene is in a disordered state, so that although graphene has a high refractive index, when the incident light is irradiated to the graphite When the graphene is placed on the antirefractive layer, the disordered graphene can enhance the refraction of light in all directions, avoid the refraction of incident light in the same direction, and achieve the effect of refraction dispersion, so that the intensity of incident light entering the coating decreases.

Step 6: Apply a layer of epoxy resin as an insulating layer on the surface of the graphene antireflection layer by a brushing method, and the thickness of the insulating layer is 15 μm.

Step 7: Apply a layer of carbon foam on the epoxy resin insulating layer by a brushing method, and the thickness of the carbon foam layer is 20 μm.

The preparation process of Examples 2-29 is the same as that of Example 1, except that the composition and thickness of each coating are different as shown in Table 1; the difference between Example 30 and Example 1 is that the ceramic A layer and the ceramic layer in step 3 are different The spraying sequence of layer B is different.

In addition, 13 groups of comparative examples were set up to carry out comparative experiments with Examples 1-30.

Table 4 is the composition and thickness of each coating of Comparative Examples 1-12:

The preparation method of Comparative Examples 1-12 is the same as that of Example 1, the only difference is that the composition and thickness of each coating are different as shown in Table 3. Comparative Example 13 is a C86100 copper alloy substrate without a coating.

The following experiments were carried out using the copper alloys provided in Examples 1-30 and Comparative Examples 1-13:

1. High temperature creep test:

The copper alloys prepared by using Examples 1-30 and Comparative Examples 1-13 were processed into tensile specimens, and a high-temperature creep test was carried out by using an electronic high-temperature creep endurance strength tester with a model of RMT-D5. The maximum test load was 50KN, the test load control accuracy is within ±5%, the deformation measurement range is 0 ~ 10mm, the rate adjustment range is 0 ~ 50mm/min ^-1 , the deformation resolution is 0.001mm, the high temperature furnace temperature control range is 200 ~ 2000 ℃, Homogeneous zone length is 150mm.

Put the specimens of Examples 1-30 and Comparative Examples 1-13 into the electronic high-temperature creep endurance testing machine, and make the specimens in a stress-free state (in the stress-free state, the specimens can expand freely, while High temperature creep is the increase in deformation over time under the combined action of temperature and stress, so the heating rate has no effect on creep). Adjust the testing machine to a stress of 50MPa and a temperature of 1300°C, and record the following data, as shown in Table 5. In Table 5, a represents the stable creep time (min) of each specimen; b represents the creep of each specimen Time to break (min).

Taking Example 1 and Comparative Example 13 as examples, as shown in Figure 2, it is the high temperature creep test curve diagram of Example 1 and Comparative Example 13, and (A) in Figure 2 represents the C86100 without coating in Comparative Example 13. Copper alloy base material, Figure 2 (B) represents the material prepared in Example 1.

It can be seen from Figure 2 that under 50MPa stress, there are three stages of creep of (A) and (B) specimens at 1300℃: the first stage is short, and the creep rate is relatively large, and it quickly transitions to In the second stage of creep, the creep rate of the second stage reaches the minimum value, and this stage is relatively long, and it is basically in the steady-state creep process; in the third stage, the creep rate increases rapidly, and the creep deformation develops rapidly until the material Creep rupture occurs. It can be found that under the stress of 50MPa and the temperature of 1300℃, the (A) test piece breaks in a very short time, indicating that the copper alloy can hardly bear the load at the temperature higher than the melting point, while the (B) test piece can hardly bear the load. The parts can maintain good mechanical properties for a long time without breaking under the condition of 1300 ℃, and have excellent high temperature resistance.

2. Salt spray corrosion test:

The copper alloys provided in Examples 1-30 and Comparative Examples 1-13 were processed into test pieces of 50 mm×25 mm×2 mm, which were then subjected to degreasing and rust removal treatments, and washed and dried. The YWX/Q-250B salt spray corrosion chamber was used as the experimental equipment, and the atmospheric corrosion environment of GB/T2967.3-2008 was simulated.

Suspend the test pieces provided in Example 1-30 and Comparative Example 1-13 in the experimental equipment, and adjust the experimental equipment to a temperature of 50±1°C, a pH of 3.0-3.1, and a reuse concentration of 5±0.5% NaCl The solution was continuously sprayed on the test pieces, and the weight loss rate of each test piece was recorded in Table 5 after a certain period of time (8, 24, 48, 72h).

As shown in Figure 3, it is the relationship between the weight loss and corrosion time of salt spray corrosion in Example 1 and Comparative Example 13. (A) in Figure 3 represents the C86100 copper alloy base material without coating in Comparative Example 13, Figure 3 In (B) represents the material prepared in Example 1.

It can be seen from Figure 3 that the two copper alloys have significantly different corrosion laws. For the specimen (A) (C86100 copper alloy specimen), with the prolongation of the corrosion time, the corrosion weight loss value shows an increasing trend. Among them, in the early stage of corrosion (8-24h), there is an oxide film on the surface of the sample, which hinders the contact between the copper alloy matrix and the solution, and the corrosion rate is small. In the middle stage of corrosion (24-48h), the Cl ^- (chloride ion) in the solution has penetrated the oxide film, and a large amount of Cl ^- is adsorbed on the substrate, which increases the pitting pits and deepens the original pitting pits, which significantly accelerates the corrosion rate. . After 48 hours of continuous spraying, the corrosion products were uniformly distributed and the thickness increased, covering almost the entire surface of the sample. Cl ^- had to pass through the corrosion products to contact the copper alloy substrate, which reduced the amount of adsorbed Cl ^- on the surface of the substrate and reduced the corrosion rate. Overall, the corrosion weight loss of C86100 copper alloy is much higher than that of the copper-based surface composite material. The copper-based surface composite material basically does not corrode due to the existence of the coating, and its quality hardly changes.

In Table 5, a represents the stable creep time (min) of each specimen; b represents the creep rupture time (min) of each specimen;

c represents the weight loss rate (v/mg.cm ² ) of the specimen after continuously spraying NaCl solution on the specimen for 8 hours;

d represents the weight loss rate (v/mg.cm ² ) of the specimen after continuously spraying NaCl solution on the specimen for 24 hours;

e represents the weight loss rate (v/mg.cm ² ) of the specimen after continuously spraying NaCl solution on the specimen for 48 hours;

f represents the weight loss rate (v/mg.cm ² ) of the specimen after continuously spraying NaCl solution on the specimen for 72 hours.

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

It can be seen from Table 5 that the copper alloy obtained by the comparative example beyond the parameter range of the present invention has greatly reduced stability at high temperature, fracture occurs in a short time, and the corrosion resistance is poor.

To sum up, by depositing an anti-oxidative composite bonding layer, a composite ceramic layer, a reflective layer, a retroreflection layer, an insulating layer and a foamed carbon layer on the copper alloy, the service temperature of the copper alloy can be raised to 100°C higher than the original melting point. -500℃, and the corrosion resistance is also greatly improved. The ultra-limit copper alloy prepared by the ultra-limit copper alloy preparation method provided by the present invention has a large service temperature range and strong corrosion resistance, and each effect of Example 1 is the best.

The above descriptions are only embodiments of the present invention, and common knowledge such as well-known specific structures and characteristics in the solution are not described too much here. It should be pointed out that for those skilled in the art, some modifications and improvements can be made without departing from the structure of the present invention. These should also be regarded as the protection scope of the present invention, and these will not affect the implementation of the present invention. Effectiveness and utility of patents. The scope of protection claimed in this application shall be based on the content of the claims, and the descriptions of the specific implementation manners in the description can be used to interpret the content of the claims.

Claims (4)

1. an ultra-limit copper alloy, comprising a copper alloy substrate, characterized in that: the surface of the copper alloy substrate is deposited with a composite bonding layer and a composite ceramic layer successively; the composite bonding layer comprises the bonding deposited on the surface of the copper alloy substrate layer and a precious metal layer deposited on the surface of the bonding layer; the composite ceramic layer includes a ceramic A layer and a ceramic B layer; a reflective layer, a retroreflection layer, an insulating layer and a foam carbon layer are deposited in sequence outside the composite ceramic layer, and the composite bonding layer The thickness of the composite ceramic layer is 100-200μm, the thickness of the composite ceramic layer is 150-500μm, the thickness of the reflective layer is 10-30μm, the thickness of the antireflection layer is 10-30μm, the thickness of the insulating layer is 10-200μm and the thickness of the foam carbon layer is 20-200μm; the composition of the bonding layer is one or a mixture of MCrAlY, NiAl, NiCr-Al, and Mo alloys, and MCrAlY is NiCrCoAlY, NiCoCrAlY, CoNiCrAlY or CoCrAlY; the composition of the noble metal layer is Au, Pt, Ru Alloy of one or more of , Rh, Pd and Ir; the composition of ceramic A layer is YSZ or rare earth zirconate (RE ₂ Zr ₂ O ₇ ), and the composition of ceramic B layer is ZrO ₂ -RETaO ₄ ; reflection The composition of the layer is a mixture of one or more of REVO ₄ , RETaO ₄ , and Y ₂ O ₃ ; the composition of the antireflection layer is a mixture of one or two of graphene or boron carbide, and graphene and carbon The spatial distribution of boron is in disordered arrangement; the composition of the insulating layer is one or a mixture of epoxy resin, phenolic resin and ABS resin. 2. the preparation method of a kind of ultra-limit copper alloy according to claim 1, is characterized in that, comprises the following steps: Step 1: depositing a bonding layer on the surface of the copper alloy substrate by using the HVOF method; and depositing a precious metal layer on the surface of the bonding layer by using the EB-PVD method, so that the bonding layer and the precious metal layer form a composite bonding layer, the composite bonding layer The total thickness of 100-200μm; Step 2: use the HVOF method to deposit a ceramic A layer and a ceramic B layer on the surface of the composite bonding layer obtained in step 1, so that the ceramic A layer and the ceramic B layer form a composite ceramic layer, and the total thickness of the composite ceramic layer is 150-500 μm; Step 3: use the HVOF method to deposit a reflection layer on the surface of the composite ceramic layer obtained in step 2, and the thickness of the reflection layer is 10-30 μm; Step 4: deposit a catadioptric layer on the surface of the reflective layer obtained in step 3 by brushing, and the thickness of the catadioptric layer is 10-30 μm; Step 5: deposit an insulating layer on the surface of the antireflection layer obtained in step 4 by brushing, and the thickness of the insulating layer is 10-200 μm; Step 6: A carbon foam layer is deposited on the surface of the insulating layer obtained in step 5 by a brushing method, and the thickness of the carbon foam layer is 20-200 μm, thereby forming an ultra-limit copper alloy. 3. The preparation method of a super-limit copper alloy according to claim 2, characterized in that: in the step 2, the ZrO ₂ -RETaO ₄ forming the ceramic B layer is a powder, and the ZrO ₂ -RETaO ₄ The particle size of the powder is 10-70 μm, and the shape is spherical. 4 . The method for preparing an ultra-limit copper alloy according to claim 3 , wherein in the step 1, before depositing the bonding layer, the surface of the copper alloy substrate is pretreated, and the pretreatment includes: 5 . Degreasing and removing impurities; after the surface pretreatment of the copper alloy substrate, the surface of the copper alloy substrate is subjected to shot blasting treatment, so that the surface roughness of the copper alloy substrate is 60-100 μm.

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