Method for relieving residual stress of yttria transparent ceramic and metal field-assisted rapid joining

Abstract

The application relates to a method for relieving residual stress of yttria transparent ceramic and metal electric field assisted rapid connection. The intermediate layer connecting material for relieving residual stress of yttria transparent ceramic and metal electric field assisted rapid connection comprises a hard metal intermediate layer, a composite intermediate layer or a soft metal intermediate layer from the side of the yttria transparent ceramic; the hard metal intermediate layer is selected from Ti and Cr, the soft metal intermediate layer is selected from Ni and Al, and the composite intermediate layer is selected from Ti / Ni, Ti / Al, Cr / Ni or Cr / Al.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of dissimilar material connection, and particularly relates to an interlayer connection material and method for relieving residual stress of electric field assisted rapid connection of yttrium oxide transparent ceramics and metal. BACKGROUND

[0002] At present, transparent ceramics with high optical quality have been widely used in the fields of laser, military and medical. Among them, yttrium oxide (Y2O3) has great application value in high-temperature window, infrared head cover, luminescent medium and semiconductor industry due to its stable performance and high transmittance in the range of 0.23 μm to 8.0 μm. However, the high brittleness and poor machinability of yttrium oxide transparent ceramics limit its engineering application. Considering the complementary relationship between ceramics and metal, connecting yttrium oxide transparent ceramics with metal is an effective way to overcome these shortcomings. The current developed connection technology of transparent ceramics and metal mainly includes adhesive bonding, brazing and diffusion bonding. The inorganic or organic adhesives used for bonding ceramics and metal are easy to soften and fail at high temperature, and the temperature range for use is limited. The brazing technology is convenient and efficient, but the actual use temperature range is low. Diffusion bonding has the advantages of high connection strength and high temperature resistance, but the long connection time deteriorates the performance of the base material, and the equipment is expensive and energy-consuming.

[0003] In recent years, electric field assisted rapid connection technology has attracted the attention of many researchers. By applying a direct current field exceeding the threshold value to the material, the connection can be completed in a very short time (seconds). Its application in the connection of yttrium oxide transparent ceramics and metal has a profound significance for the development and application of yttrium oxide transparent ceramics. However, due to the mismatch of the thermal expansion coefficients of metal and ceramics, the residual stress of electric field assisted direct connection is too large, which seriously reduces the quality and reliability of the joint. Therefore, it is necessary to design a method for relieving the residual stress of electric field assisted rapid connection of yttrium oxide transparent ceramics and metal, and effectively control the influence of residual stress on the performance of the connection. SUMMARY

[0004] In view of the above problems, the application provides an interlayer connection material and method for relieving the residual stress of electric field assisted rapid connection of yttrium oxide transparent ceramics and metal. The purpose is to design and regulate the transition reaction interface of the interlayer to reduce the generation of residual stress in the joint area, and thus greatly improve the connection performance.

[0005] In one aspect, the application provides an interlayer connection material for relieving the residual stress of electric field assisted rapid connection of yttrium oxide transparent ceramics and metal. The interlayer connection material comprises a hard metal interlayer, a soft metal interlayer or a composite interlayer from the side of yttrium oxide transparent ceramics. The hard metal interlayer is selected from Ti and Cr, the soft metal interlayer is selected from Ni and Al, and the composite interlayer is selected from Ti / Ni, Ti / Al, Cr / Ni or Cr / Al.

[0006] The interlayer material provided by the present invention, which can alleviate residual stress in the connection between yttrium oxide transparent ceramic and metal, includes a specific hard metal interlayer, a soft metal interlayer, or a composite interlayer. In the composite interlayer, the hard metal interlayers of Ti and Cr are positioned closer to the yttrium oxide transparent ceramic, while the soft metal interlayers of Ni and Al are positioned closer to the metal to be connected. This achieves a gradient transition in thermal expansion coefficients, effectively alleviating residual stress.

[0007] The intermediate layer used in the present invention includes a hard metal intermediate layer, a soft metal intermediate layer or a composite intermediate layer. Compared with the electric field assisted direct connection without adding an intermediate layer, the present invention can effectively alleviate the residual stress generated during the connection process, improve the connection strength and quality, and the required connection time is significantly shortened, and the required current density is also significantly reduced. The method provided by the present invention for alleviating the residual stress of yttrium oxide transparent ceramic and metal electric field assisted rapid connection obtains a joint shear strength of ≥40MPa, and the mechanical properties of the connector are significantly improved. This is because the intermediate layer added by the present invention contains active elements, which can make the diffusion reaction process faster. At the same time, under the electromigration effect of the applied current, the diffusion rate of metal atoms is further accelerated. Therefore, the combined effect of the two further shortens the time required for connection.

[0008] The thickness of the hard metal intermediate layer is 400-800nm, the thickness of the soft metal intermediate layer is 400-800nm; the thickness of the composite intermediate layer is 600-800nm. Preferably, the thickness of the hard metal intermediate layer in the composite intermediate layer is 300-400nm, and the thickness of the soft metal intermediate layer is 300-400nm. If the intermediate layer is too thin, the reaction is insufficient, and almost all of the soft metal in the intermediate layer reacts with the parent material, thus having little effect on relieving residual stress. If the intermediate layer is too thick, it will lead to excessive reaction, and excessive products will increase the brittleness of the joint, which is not conducive to improving the connection strength.

[0009] The room temperature flexural strength of the yttrium oxide transparent ceramic to be connected is ≥150 MPa, the elastic modulus is ≥160 GPa, and the optical transmittance at a wavelength of 1050 nm is not less than 80%.

[0010] The metal to be joined comprises one of a titanium-based alloy, an iron-based alloy or a monel alloy. Preferably, the metal to be joined comprises titanium alloy TC4 (Ti-6Al-4V), Kovar alloy 4J29, iron-cobalt-nickel alloy 4J33, or monel alloy Monel400 (Ni68Cu28Fe).

[0011] In another aspect, the present application also provides a method for relieving the residual stress of yttria transparent ceramic and metal electric field assisted rapid connection by using the intermediate layer connecting material, comprising: (1) preparing the intermediate layer on the surface of the yttria transparent ceramic to be connected by using the magnetron sputtering method after grinding, polishing and ultrasonic cleaning pretreatment; (2) assembling the sample to be connected in the order of first electrode / yttria transparent ceramic / intermediate layer / metal / second electrode and placing it in the electric field assisted diffusion connection device, applying an axial pressure of 0.1-1 MPa to the sample to be connected, heating it to 875-925 ℃ under a vacuum degree of 6*10 -3 Pa, and applying an electric field to the sample to be connected by electrodes, when the current density reaches 1-5 mA / mm 2 2, continuing to pass electricity and heat preservation for 30-180 s, and finally cooling to room temperature at a cooling rate of 3-5 ℃ / min to obtain a yttria transparent ceramic / intermediate layer / metal connecting piece.

[0012] The advantages of the present application in preparing the intermediate layer by using the magnetron sputtering method mainly include two points, one is the diversity of material selection, and the magnetron sputtering has no requirement on the target material such as high temperature resistance and heat radiation resistance, while the thermal spraying method has certain limitations in the selection of the intermediate layer material; the other is that the intermediate layer prepared by the magnetron sputtering method has better quality, high bonding strength and no obvious defects compared with the thermal spraying method and the like.

[0013] In a preferred scheme, the surfaces of the yttria transparent ceramic and the metal to be connected are subjected to grinding and polishing treatment and are placed in an ethanol solution for ultrasonic cleaning so that the surface roughness Ra of the surface of the yttria transparent ceramic to be connected is ≤0.1 μm, and the surface roughness Ra of the surface of the metal to be connected is ≤5 μm.

[0014] Preferably, in step (1), the magnetron sputtering method comprises: placing the pretreated yttria transparent ceramic into a magnetron sputtering sample chamber, vacuumizing to 0.05-0.1 Pa, and performing radio frequency cleaning on the yttria transparent ceramic surface to be sputtered for 2-5 min under a power of 75-85 W; then vacuumizing the sputtering cavity to 5*10 -3 -8*10 -3 Pa and heating to 175-225 ℃, pre-sputtering for 5-10 min under a power of 200-250 W, and then opening the target material baffle and base rotation switch and performing magnetron sputtering under a sputtering power of 200-250 W.

[0015] Preferably, in step (1), the intermediate layer comprises a hard metal intermediate layer, a soft metal intermediate layer or a composite intermediate layer; wherein the sputtering time of the hard metal intermediate layer is 20-40 min, the sputtering time of the soft metal intermediate layer is 20-40 min, the sputtering time of the hard metal intermediate layer in the composite intermediate layer is 15-20 min, and the sputtering time of the soft metal intermediate layer is 15-20 min.

[0016] Preferably, in step (1), the hard metal intermediate layer is Ti or Cr, the soft metal intermediate layer is Ni or Al, and the composite intermediate layer comprises one of Ti / Ni, Ti / Al, Cr / Ni, and Cr / Al.

[0017] Preferably, in step (1), the thickness of the hard metal intermediate layer is 400-800 nm, and the thickness of the soft metal intermediate layer is 400-800 nm; when the composite intermediate layer is sputtered, the thickness of the hard metal intermediate layer is 300-400 nm, and the thickness of the soft metal intermediate layer is 300-400 nm.

[0018] Preferably, in step (2), the direction of the applied electric field is from the first electrode to the second electrode, i.e., from the yttria transparent ceramic side to the intermediate layer and then to the metal side.

[0019] The mechanism of the present application for relieving the residual stress of the yttria transparent ceramic and the metal in the electric field assisted rapid connection is that the soft metal intermediate layer uses the plastic deformation capacity of the soft metal to relieve the residual stress of the joint; the hard metal intermediate layer, due to its low thermal expansion coefficient, is close to the ceramic base material and can relieve the residual stress; and the composite intermediate layer relieves the residual stress through the gradient transition of the thermal expansion coefficient. The traditional intermediate layer, such as a metal foil, is too thick for the present application, and the intermediate layer prepared by the magnetron sputtering method of the present application can precisely adjust the thickness to nm level, more effectively relieve the residual stress, and has good bonding strength.

[0020] The reason for applying a direct current electric field in the present application is that the threshold direct current electric field is applied to stimulate the generation of a large number of oxygen defects in the ceramic, so as to realize the connection within seconds. The mechanism of the electric field assisted connection of the ceramic and the metal under an alternating current electric field is essentially different from that under the direct current electric field of the present application. The greatest advantage of applying a direct current electric field in the present application is that the connection time can be shortened from hours to seconds, thereby avoiding the damage to the base material itself caused by the long high-temperature connection time.

[0021] The main reaction of the generation of oxygen defects is as follows:

[0022]

[0023] As can be seen, the gas concentration gradient in the vacuum environment of the present application is more conducive to the release of oxygen, i.e., more conducive to the reaction and the generation of oxygen defects. Compared with the alternating current electric field, the mechanism of the direct current electric field is obviously different. The alternating current electric field assisted diffusion connection mainly uses the thermal effect of the electric current joule effect, but still needs a long time (h); the threshold electric field used in the present application mainly stimulates a large number of oxygen defects in the ceramic by applying a threshold direct current electric field, so as to realize the connection within seconds and avoid the damage to the base material itself caused by the long connection time, wherein the electric current joule heat effect is only a secondary effect.

[0024] The intermediate layer species, the intermediate layer thickness, the current density, the connection time, the connection temperature and the like of the present application play a decisive role in the rapid connection of yttria transparent ceramic and metal. The intermediate layer species is directly linked to the actual effect of the reaction product and the mitigation of residual stress. The intermediate layer thickness affects the reaction degree, if the intermediate layer is too thin, the reaction is insufficient, and the soft metal of the intermediate layer almost reacts with the base material, so that the effect of mitigating residual stress is small; if the intermediate layer is thicker, the reaction is excessive, and the excessive product makes the joint brittle, which is not conducive to the improvement of the connection strength. If the current density is too large, the excessive brittle phase generated at the connection interface will affect the connection strength; if the current density is too small, the reaction is insufficient to achieve effective combination. If the connection time is too long, the interface reaction is excessive, which will affect the connection strength; if the connection time is too short, the reaction is incomplete and the connection cannot be achieved. If the connection temperature is too low, the reaction cannot be fully carried out, and if the connection temperature is too high, the reaction is too intense, which will affect the strength.

[0025] Advantages

[0026] The method for mitigating the residual stress of the field-assisted rapid connection of yttria transparent ceramic and metal of the present application has the following advantages:

[0027] (1) Compared with the field-assisted direct connection without adding an intermediate layer, the present application realizes the indirect connection of transparent ceramic and metal under the joint action of electric field and current by designing the intermediate layer material, which can effectively mitigate the residual stress generated in the connection process and improve the connection strength and quality.

[0028] (2) Compared with the field-assisted direct connection without adding an intermediate layer, the field-assisted connection process is easier after adding a metal intermediate layer, the required connection time is significantly shortened, and the required current density is also significantly reduced, which has greater advantages in production efficiency.

[0029] (3) The present application can improve the mitigation effect of residual stress by adjusting the intermediate layer thickness, current density, connection time and the like. If the intermediate layer is too thin, the reaction is insufficient, and the soft metal of the intermediate layer almost reacts with the base material, so that the effect of mitigating residual stress is small; if the intermediate layer is too thick, the generation of excessive brittle phase in the connection interface will affect the joint strength. If the current density is too large, the reaction is excessive and excessive brittle phase is generated, which is not conducive to the mitigation of residual stress; if the current density is too small, the reaction is insufficient to achieve effective combination. If the connection time is too long, the intermediate layer material reacts excessively with the base material, which is not conducive to the mitigation of residual stress; if the connection time is too short, the reaction is incomplete and effective connection cannot be achieved. Different process parameters are coupled and affect each other, so it is necessary to adjust the process parameters according to the specific intermediate layer species and thickness to effectively improve the mitigation effect of residual stress. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1Schematic diagram of the electric field assisted diffusion bonding device used in Example 1;

[0031] Figure 2 This is a scanning electron microscope image of the interface between the yttrium oxide transparent ceramic / Ni / TC4 titanium alloy in Example 1;

[0032] Figure 3 This is the X-ray diffraction pattern at the connection interface of the yttrium oxide transparent ceramic / Ni / TC4 titanium alloy connector of Example 1. DETAILED DESCRIPTION

[0033] To further illustrate the content, features and practical effects of the present invention, the present invention is described in detail below in conjunction with the embodiments. It should be noted that the modification method of the design of the present invention is not limited to these specific embodiments. Without departing from the spirit and connotation of the design of the present invention, equivalent replacements and modifications made by those skilled in the art based on the content of the present invention are also within the scope of the present invention.

[0034] The following is an exemplary description of a method for alleviating residual stress in electric field-assisted rapid connection between yttria transparent ceramic and metal using the intermediate layer connection material provided by the present invention.

[0035] An intermediate layer is prepared by magnetron sputtering on the surface to be connected of the yttrium oxide transparent ceramic that has been pretreated by grinding, polishing and ultrasonic cleaning.

[0036] In an optional embodiment, the surfaces of the yttrium oxide transparent ceramic and metal to be joined are ground and polished, and then ultrasonically cleaned in an ethanol solution to achieve a surface roughness Ra ≤ 0.1 μm for the yttrium oxide transparent ceramic surface and a surface roughness Ra ≤ 5 μm for the metal surface. Excessive roughness on the ceramic side can affect the quality of the intermediate layer prepared by magnetron sputtering. However, the roughness requirement on the metal side, which contacts the intermediate layer, can be appropriately reduced.

[0037] The magnetron sputtering method comprises: placing the pretreated yttrium oxide transparent ceramic into a magnetron sputtering sample chamber, evacuating the chamber to a vacuum of 0.05 to 0.1 Pa, and performing radio frequency cleaning on the surface of the yttrium oxide transparent ceramic to be sputtered for 2 to 5 minutes at a power of 75 to 85 W; then evacuating the sputtering chamber to a vacuum of 5×10 -3 ~8×10 -3 Pa and heat to 175-225 ° C, pre-sputter at a power of 200-250 W for 5-10 minutes, then open the target baffle and base rotation switch, and perform magnetron sputtering at a sputtering power of 200-250 W.

[0038] The intermediate layer comprises a hard metal intermediate layer, a soft metal intermediate layer or a composite intermediate layer; wherein the sputtering time of the hard metal intermediate layer is 20-40 min, the sputtering time of the soft metal intermediate layer is 20-40 min, the sputtering time of the hard metal intermediate layer in the composite intermediate layer is 15-20 min, and the sputtering time of the soft metal intermediate layer is 15-20 min. Too long sputtering time of the intermediate layer will result in too thick intermediate layer, which is not conducive to residual stress relief, and will result in failure to achieve effective connection.

[0039] The hard metal intermediate layer is selected from Ti or Cr, because its thermal expansion coefficient is close to that of the ceramic material, and can relieve the joint residual stress to a certain extent; the soft metal intermediate layer is selected from Ni or Al, which utilizes the plastic deformation and creep deformation of the soft metal to relieve the joint residual stress; the composite intermediate layer is selected from one of Ti / Ni, Ti / Al, Cr / Ni and Cr / Al, so as to realize the gradient transition of the thermal expansion coefficient of the connection interface, thereby relieving the joint residual stress. As described above, the present application excites a large number of oxygen defects by a threshold electric field to achieve ultra-fast connection within seconds, and the main role is to reduce the required connection time to avoid damage to the base material. In order to further improve the connection strength, the present application selects to add a soft metal layer, a hard metal layer and a composite metal layer. The selection of the soft metal intermediate layer utilizes the plastic deformation ability of the soft metal to relieve the joint residual stress; the selection of the hard metal intermediate layer can relieve the residual stress because of its low thermal expansion coefficient, which is close to that of the ceramic base material; the selection of the composite intermediate layer is to relieve the residual stress by the gradient transition of the thermal expansion coefficient. It is found in specific tests that the addition of these intermediate metal layers promotes diffusion and reaction, further shortening the connection time and the required current density.

[0040] The thickness of the hard metal intermediate layer is controlled to be 400-800 nm; the thickness of the soft metal intermediate layer is controlled to be 400-800 nm; when the composite intermediate layer is sputtered, the total thickness of the composite intermediate layer is controlled to be 600-800 nm, wherein the thickness of the hard metal intermediate layer is controlled to be 300-400 nm, and the thickness of the soft metal intermediate layer is controlled to be 300-400 nm. If the intermediate layer is too thin, the residual stress cannot be effectively relieved; if the intermediate layer is too thick, the generation of excessive brittle phase in the connection interface will affect the joint strength.

[0041] The sample to be connected is assembled in the order of first electrode / yttrium oxide transparent ceramic / intermediate layer / metal / second electrode and placed in an electric field assisted diffusion connection device, an axial pressure of 0.1-1 MPa is applied to the sample to be connected, and the sample to be connected is heated to 875-925 DEG C under a vacuum degree of ≤6*10 -3 Pa, and an electric field is applied to the sample to be connected through the electrodes, when the current density reaches 1-5 mA / mm 2After that, the power is kept on for 30-180s, and finally, the temperature is cooled to room temperature at a rate of 3-5℃ / min, and the yttria transparent ceramic / interlayer / metal connector is obtained.

[0042] In an optional embodiment, the direction of the applied electric field is from the first electrode to the second electrode, i.e. from the yttria transparent ceramic side to the intermediate layer and finally to the metal side.

[0043] The axial pressure is preferably 0.5MPa, and too small pressure cannot achieve effective connection; and too large vacuum degree in the furnace chamber is not conducive to creating an environment for promoting oxygen defects.

[0044] The heating temperature is preferably 900℃, and too low heating temperature will result in insufficient reaction, and too high heating temperature will result in excessive reaction and residual stress.

[0045] The cooling rate is preferably 3℃ / min, and too low cooling rate will result in a long connection process and affect the efficiency, and too high cooling rate will result in excessive residual stress.

[0046] The electric field assisted rapid connection of the present application is performed in a vacuum environment, and the purpose is to promote the generation of oxygen defects and prevent metal oxidation. Compared with the prior art in a non-vacuum environment, the vacuum environment has the following advantages: the gas concentration gradient in the vacuum environment is more conducive to the release of oxygen, i.e. more conducive to the reaction and the generation of oxygen defects, and the oxidation of the metal base material can be effectively avoided.

[0047] The current density can be controlled to be 1-5mA / mm 2 If the current density is too large, the excessive brittle phase generated at the connection interface will affect the connection strength; and if the current density is too small, the reaction is insufficient and effective bonding cannot be achieved. The time for maintaining the constant current density, i.e. the connection time, can be 30-180s. If the connection time is too long, the interface reaction is excessive and the connection strength is damaged; and if the connection time is too short, the reaction is incomplete and the connection cannot be achieved.

[0048] The present application effectively relieves the residual stress at the connection interface by a method for relieving the residual stress of the electric field assisted rapid connection of yttria transparent ceramic and metal under the condition of adding a hard metal intermediate layer, a soft metal intermediate layer or a composite intermediate layer. Compared with the electric field assisted direct connection of yttria transparent ceramic and metal, the addition of the intermediate layer can significantly improve the joint quality and reliability, and further shorten the required connection time.

[0049] The following examples are further illustrated in detail to explain the present application. It should also be understood that the following examples are only used to further illustrate the present application, and cannot be understood as limiting the scope of protection of the present application. Some non-essential improvements and adjustments made by those skilled in the art according to the above content of the present application are within the scope of protection of the present application. The specific process parameters and the like described in the following examples are only one example in the appropriate range, i.e. those skilled in the art can make appropriate selection within the range according to the description herein, and are not limited to the specific values of the examples below.

[0050] Example 1

[0051] In this example 1, Ni is used as a soft metal intermediate layer to electric field assisted connect yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic parent material at room temperature is ≥160 MPa, the elastic modulus is ≥150 GPa, and the optical transmittance at 1050 nm wavelength is not less than 80%. The specific connection method is as follows:

[0052] (1) The ceramic parent material and the metal parent material are processed into blocks with a size of 15×12×2 mm 3 . The surfaces to be connected of the two are ground and polished respectively, and the impurities and oil stains are removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic is ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the TC4 titanium alloy is ≤5 μm.

[0053] (2) The yttria transparent ceramic after ultrasonic cleaning is placed in a magnetron sputtering sample chamber, the sample chamber is vacuumed to 10 - 1 Pa, and the transparent ceramic surface to be sputtered is cleaned by radio frequency for 3 min at a power of 80 W. Then the sputtering cavity is vacuumed, and the sample feeding process is carried out. When the vacuum degree of the magnetron sputtering cavity reaches 6×10 -3 Pa, the temperature is raised to 200℃, the Ni target is pre-sputtered at a power of 200 W for 10 min, and then the target baffle and the base rotation switch are opened. The Ni target is magnetron sputtered at a sputtering power of 230 W for 30 min.

[0054] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer is combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode (as shown in Figure 1 ). The assembly is assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa is applied to the assembly, and when the vacuum degree in the furnace cavity reaches 6×10 -3 Pa, the temperature is raised to 900℃, and then an electric field is applied in the direction from the first electrode to the second electrode. When the current density reaches 1 mA / mm 2 , it is maintained for 60 s. The yttria transparent ceramic / Ni / TC4 titanium alloy connecting piece is obtained by cooling to room temperature at a cooling rate of 3℃ / min.

[0055] The joint shear strength of the connecting piece prepared in this embodiment 2 was 69 MPa, and the thickness of the Ni intermediate layer was 550 nm, detected by a universal testing machine CLY30.

[0056] Figure 2 The scanning electron microscope image of the yttria transparent ceramic / Ni / TC4 titanium alloy connecting interface of embodiment 1 showed that the connecting piece achieved effective connection, and the interface had no obvious defects and good bonding. The intermediate layer Ni reacted with the base material through diffusion, and the reaction product was distributed at the α phase grain boundary of TC4.

[0057] Figure 3 The X-ray diffraction image of the connecting interface of the yttria transparent ceramic / Ni / TC4 titanium alloy connecting body of embodiment 1 showed that the relevant reaction product was generated at the interface after connection.

[0058] Embodiment 2

[0059] In this embodiment 2, Ni was used as a soft metal intermediate layer to electric field assisted connect yttria transparent ceramic and Monel400 alloy, wherein the yttria transparent ceramic base material had a room temperature bending strength≥160 MPa, an elastic modulus≥150 GPa, and an optical transmittance at 1050 nm wavelength not less than 80%. The specific connection method was as follows:

[0060] (1) The ceramic base material and the metal base material were processed into blocks with a size of 15×12×2 mm 3 . The surfaces to be connected of the two were ground and polished, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic was≤0.1 μm, and the surface roughness Ra of the surface to be connected of the Monel400 alloy was≤5 μm.

[0061] (2) The yttria transparent ceramic after ultrasonic cleaning was placed in a magnetron sputtering sample chamber, the sample chamber was vacuumed to 10 - 1 Pa, and the transparent ceramic surface to be sputtered was cleaned by radio frequency for 3 min under a power of 80 W. Then the sputtering cavity was vacuumed, and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering cavity reached 5×10 -3 Pa, the temperature was raised to 200℃, the Ni target was pre-sputtered for 10 min at a power of 200 W, and then the target baffle and the base rotating switch were opened. The Ni target was magnetron sputtered at a sputtering power of 210 W for 25 min.

[0062] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer was combined with the Monel400 alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and was assembled in an electric field assisted diffusion connection device. An axial pressure of 0.5 MPa was applied to the combined piece, and the vacuum degree in the furnace cavity reached 4×10-3 After heating to 900℃, an electric field is applied in the direction of the first electrode to the second electrode, and when the current density reaches 3 mA / mm 2 After maintaining for 120 s, the temperature is cooled to room temperature at a rate of 3℃ / min, and a yttria transparent ceramic / Ni / Monel 400 alloy connecting piece is obtained.

[0063] The connecting piece joint prepared in this embodiment 5 has a shear strength of 62 MPa, and the thickness of the Ni intermediate layer is 460 nm.

[0064] Embodiment 3

[0065] In this embodiment 3, Al is used as the soft metal intermediate layer to electric field assisted connect yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic parent material at room temperature is ≥160 MPa, the elastic modulus is ≥150 GPa, and the optical transmittance at 1050 nm is not less than 80%. The specific connecting method is as follows:

[0066] (1) The ceramic parent material and the metal parent material are processed into blocks with a size of 15×12×2 mm 3 , the surfaces to be connected of the two are ground and polished, and the impurities and oil stains are removed by ultrasonic cleaning in an ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic is ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the TC4 titanium alloy is ≤5 μm.

[0067] (2) The yttria transparent ceramic after ultrasonic cleaning is placed in a magnetron sputtering sample chamber, the sample chamber is vacuumed to 10 - 1 Pa, and the transparent ceramic surface to be sputtered is cleaned by radio frequency for 3 min at a power of 80 W. Then the sputtering cavity is vacuumed, and the sample feeding process is carried out. When the vacuum degree of the magnetron sputtering cavity reaches 8×10 -3 Pa, the temperature is raised to 200℃, the Al target is pre-sputtered at a power of 200 W for 10 min, and then the target shutter and the base rotation switch are opened. The Al target is magnetron sputtered at a sputtering power of 225 W for 20 min.

[0068] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer is combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and is assembled in the electric field assisted diffusion connecting device. An axial pressure of 0.5 MPa is applied to the combined piece, and when the vacuum degree in the furnace cavity reaches 6×10 -3 Pa, the temperature is heated to 900℃, an electric field is applied in the direction of the first electrode to the second electrode, and when the current density reaches 4 mA / mm 2 After maintaining for 120 s, the temperature is cooled to room temperature at a rate of 3℃ / min, and a yttria transparent ceramic / Al / TC4 titanium alloy connecting piece is obtained.

[0069] The joint shear strength of the connecting piece prepared in Example 3 was 53 MPa, and the thickness of the Al intermediate layer was 360 nm, detected by a universal testing machine CLY30.

[0070] Example 4

[0071] In Example 4, Al was used as a soft metal intermediate layer to electric field-assisted connect yttrium oxide transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttrium oxide transparent ceramic at room temperature was ≥160 MPa, the elastic modulus was ≥150 GPa, and the optical transmittance at 1050 nm was not less than 80%. The specific connecting method was as follows:

[0072] (1) The ceramic and metal parent materials were processed into blocks with the size of 15x12x2 mm 3 . The surfaces to be connected of the two were ground and polished, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttrium oxide transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the TC4 titanium alloy was ≤5 μm.

[0073] (2) The yttrium oxide transparent ceramic after ultrasonic cleaning was placed in a magnetron sputtering sample chamber, the sample chamber was vacuumed to 10 - 1 Pa, and the transparent ceramic surface to be sputtered was cleaned by radio frequency for 3 min under a power of 80 W. Then the sputtering cavity was vacuumed, and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering cavity reached 8x10 -3 Pa, the temperature was raised to 200℃, the Al target was pre-sputtered for 10 min at a power of 200 W, and then the target shutter and base rotation switch were opened. The Al target was magnetron sputtered for 30 min at a sputtering power of 210 W.

[0074] (3) The yttrium oxide transparent ceramic after magnetron sputtering of the intermediate layer was combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and assembled in an electric field-assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and when the vacuum degree in the furnace cavity reached 5x10 -3 Pa, the temperature was raised to 900℃, and then an electric field was applied in the direction from the first electrode to the second electrode. When the current density reached 3.5 mA / mm 2 , it was maintained for 30 s. The temperature was cooled to room temperature at a rate of 3℃ / min to obtain a yttrium oxide transparent ceramic / Al / TC4 titanium alloy connecting piece.

[0075] The joint shear strength of the connecting piece prepared in Example 4 was 48 MPa, and the thickness of the Al intermediate layer was 550 nm, detected by a universal testing machine CLY30.

[0076] Example 5

[0077] This embodiment 5 uses Ti as the hard metal interlayer to field-assisted join yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic at room temperature is ≥160 MPa, the elastic modulus is ≥150 GPa, and the optical transmittance at 1050 nm is not less than 80%. The specific joining method is as follows:

[0078] (1) The ceramic and metal parent materials are processed into 15x12x2mm 3 blocks, and the surfaces to be joined of the two are ground and polished, respectively, and ultrasonic cleaning is performed in ethanol solution to remove impurities and oil stains. The surface roughness Ra of the surface to be joined of the required yttria transparent ceramic is ≤0.1μm, and the surface roughness Ra of the surface to be joined of the TC4 titanium alloy is ≤5μm.

[0079] (2) The yttria transparent ceramic after ultrasonic cleaning is placed in a magnetron sputtering sample chamber, the sample chamber is vacuumed to 10 - 1 Pa, and the transparent ceramic surface to be sputtered is radio frequency cleaned at a power of 80W for 3min. Then the sputtering cavity is vacuumed, and the sample feeding process is performed. When the vacuum of the magnetron sputtering cavity reaches 8x10 -3 Pa, it is heated to 200℃, the Ti target is pre-sputtered at a power of 200W for 10min, then the target shutter and base rotation switch are opened, and the Ti target is magnetron sputtered at a power of 200W for 30min.

[0080] (3) The yttria transparent ceramic after magnetron sputtering of the interlayer is combined with the TC4 titanium alloy in the order of electrode / ceramic / interlayer / metal / electrode, and is assembled in a field-assisted diffusion joining device. An axial pressure of 0.5MPa is applied to the assembly, and when the vacuum degree in the furnace cavity reaches 6x10 -3 Pa, it is heated to 900℃, and then an electric field is applied in the direction from the first electrode to the second electrode, and when the current density reaches 1mA / mm 2 , it is maintained for 180s, and then it is cooled to room temperature at a cooling rate of 3℃ / min to obtain a yttria transparent ceramic / Ti / TC4 titanium alloy joint.

[0081] The joint shear strength of the joint prepared in this embodiment 5 is 50MPa, and the thickness of the Ti interlayer is 450nm, which is detected by a universal testing machine CLY30.

[0082] Embodiment 6

[0083] This embodiment 6 uses Ti as the hard metal interlayer to field-assisted join yttria transparent ceramic and 4J29 alloy, wherein the bending strength of the yttria transparent ceramic at room temperature is ≥160 MPa, the elastic modulus is ≥150 GPa, and the optical transmittance at 1050 nm is not less than 80%. The specific joining method is as follows:

[0084] (1) The ceramic and metal parent materials were processed into 15x12x2mm blocks, and the surfaces of the two to be connected were ground and polished, respectively, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the to-be-connected surface of the desired yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the to-be-connected surface of the 4J29 alloy was ≤5 μm. 3

[0085] (2) The yttria transparent ceramic after ultrasonic cleaning was placed in a magnetron sputtering sample chamber, the sample chamber was vacuumed to 10 - 1 Pa, and the transparent ceramic surface to be sputtered was radio frequency cleaned at a power of 80 W for 3 min. Then the sputtering cavity was vacuumed, and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering cavity reached 7x10 -3 Pa, the temperature was raised to 200℃, the Ti target was pre-sputtered at a power of 200 W for 10 min, and then the target shutter and base rotation switch were opened. The Ti target was magnetron sputtered at a sputtering power of 250 W for 20 min.

[0086] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer was combined with the 4J29 alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and when the vacuum degree in the furnace cavity reached 5x10 -3 Pa, the temperature was raised to 900℃, and then an electric field was applied in the direction from the first electrode to the second electrode. When the current density reached 5 mA / mm 2 , it was maintained for 30 s. The temperature was cooled to room temperature at a rate of 3℃ / min to obtain a yttria transparent ceramic / Ti / 4J29 alloy connecting piece.

[0087] The connecting piece joint prepared in Example 6 had a shear strength of 45 MPa, and the Ti intermediate layer had a thickness of 325 nm, as detected by the universal testing machine CLY30.

[0088] Example 7

[0089] In this example 7, Cr was used as a hard metal intermediate layer to electric field assisted connect yttria transparent ceramic and TC4 titanium alloy. The yttria transparent ceramic parent material had a room temperature bending strength ≥160 MPa, an elastic modulus ≥150 GPa, and an optical transmittance at 1050 nm not less than 80%. The specific connection method is as follows:

[0090] (1) The ceramic and metal parent materials were processed into 15x12x2mm blocks, and the surfaces of the two to be connected were ground and polished, respectively, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the to-be-connected surface of the desired yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the to-be-connected surface of the 4J29 alloy was ≤5 μm. 3 ​The two surfaces to be connected of the bulk-shaped yttria transparent ceramic and the bulk-shaped TC4 titanium alloy were ground and polished, respectively, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the TC4 titanium alloy was ≤5 μm.

[0091] (2) The yttria transparent ceramic cleaned by ultrasonic cleaning was placed in a magnetron sputtering sample chamber, and the sample chamber was vacuumed to 10 - 1 Pa, and the surface to be sputtered of the transparent ceramic was cleaned by radio frequency for 3 min at a power of 80 W. Then, the sputtering cavity was vacuumed, and a sample feeding process was performed. When the vacuum of the magnetron sputtering cavity reached 5×10 -3 Pa, the temperature was increased to 200 ℃, the Cr target was pre-sputtered at a power of 200 W for 10 min, the target shutter and the base rotation switch were opened, and the Cr target was magnetron sputtered at a sputtering power of 220 W for 40 min.

[0092] (3) The yttria transparent ceramic after the magnetron sputtering of the intermediate layer was combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and was assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and after the vacuum degree in the furnace cavity reached 3×10 -3 Pa, the temperature was increased to 900 ℃, an electric field was applied in the direction from the first electrode to the second electrode, and when the current density reached 2 mA / mm 2 , it was maintained for 120 s, and the temperature was cooled to room temperature at a cooling rate of 3 ℃ / min, to obtain a yttria transparent ceramic / Cr / TC4 titanium alloy connecting piece.

[0093] It was detected by a universal testing machine CLY30 that the shear strength of the connecting piece prepared in Example 7 was 43 MPa, and the thickness of the Cr intermediate layer was 580 nm.

[0094] Example 8

[0095] In this example 8, Cr was used as a hard metal intermediate layer to electric field assisted connect yttria transparent ceramic and 4J33 alloy, wherein the bending strength of the yttria transparent ceramic at room temperature was ≥160 MPa, the elastic modulus was ≥150 GPa, and the optical transmittance at 1050 nm was not less than 80%. The specific connecting method was as follows:

[0096] (1) The ceramic matrix and the metal matrix were processed into bulk-shaped pieces with a size of 15×12×2 mm 3 , and the surfaces to be connected of the two were ground and polished, respectively, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the 4J33 alloy was ≤5 μm.

[0097] (2) Put the ultrasonic cleaned yttria transparent ceramic into the magnetron sputtering sample chamber, vacuumize the sample chamber to 10 - 1 Pa, and perform radio frequency cleaning on the transparent ceramic surface to be sputtered at 80W power for 3min. Then vacuumize the sputtering chamber, and perform sample feeding process. When the vacuum degree of the magnetron sputtering chamber reaches 8x10 -3 Pa, heat to 200℃, pre-sputter the Cr target at 200W power for 10min, open the target shutter and the base rotation switch, and perform magnetron sputtering on the Cr target at 200W sputtering power for 30min.

[0098] (3) Assemble the yttria transparent ceramic after magnetron sputtering of the intermediate layer and the 4J33 alloy in the order of electrode / ceramic / intermediate layer / metal / electrode in the field-assisted diffusion bonding device. Apply an axial pressure of 0.5MPa to the assembly, heat to 900℃ after the vacuum degree in the furnace chamber reaches 5x10 -3 Pa, and apply an electric field in the direction from the first electrode to the second electrode, maintain for 90s when the current density reaches 2.5mA / mm 2 2, and cool to room temperature at a cooling rate of 3℃ / min to obtain a yttria transparent ceramic / Cr / 4J33 alloy connecting piece.

[0099] The connecting piece prepared in this embodiment 8 is detected by the universal testing machine CLY30, and the shear strength of the connecting piece is 45MPa, and the thickness of the Cr intermediate layer is 440nm.

[0100] Embodiment 9

[0101] This embodiment 9 uses Ti / Ni as a composite intermediate layer to field-assisted connect yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic parent material at room temperature is ≥160MPa, the elastic modulus is ≥150GPa, and the optical transmittance at 1050nm wavelength is not less than 80%. The specific connecting method is as follows:

[0102] (1) Process the ceramic parent material and the metal parent material into blocks with the size of 15x12x2mm 3 2, respectively grind and polish the connecting surfaces of the two, and ultrasonically remove impurities and oil stains in ethanol solution. The surface roughness Ra of the connecting surface of the required yttria transparent ceramic is ≤0.1μm, and the surface roughness Ra of the connecting surface of the TC4 titanium alloy is ≤5μm.

[0103] (2) Put the ultrasonic cleaned yttria transparent ceramic into the magnetron sputtering sample chamber, vacuumize the sample chamber to 10 - 1Pa and the transparent ceramic was radio frequency cleaned for 3 min at 80 W power. Then the sputtering chamber was vacuumized and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering chamber reached 6 x 10 -3 Pa, the temperature was raised to 200℃, the Ti target was pre-sputtered for 10 min at 200 W power, then the target shutter and the base rotation switch were opened, the Ti target was magnetron sputtered for 15 min at 235 W power, then the Ni target was pre-sputtered for 10 min, the target shutter and the base rotation switch were opened, and the Ni target was magnetron sputtered for 15 min at 235 W power.

[0104] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer was combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and was assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and after the vacuum degree in the furnace chamber reached 6 x 10 -3 Pa, the temperature was raised to 900℃, then an electric field was applied in the direction from the first electrode to the second electrode, and when the current density reached 1.5 mA / mm 2 , it was maintained for 180 s, and the temperature was cooled to room temperature at a rate of 3℃ / min, to obtain a yttria transparent ceramic / Ti / Ni / TC4 titanium alloy connecting piece.

[0105] The connecting piece prepared in this embodiment 9 was detected by a universal testing machine CLY30, and the shear strength of the connecting piece was 78 MPa, and the thickness of the Ti / Ni intermediate layer was 500 nm.

[0106] Embodiment 10

[0107] In this embodiment 10, Ti / Al was used as a composite intermediate layer to electric field assisted connect yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic at room temperature was ≥160 MPa, the elastic modulus was ≥150 GPa, and the optical transmittance at 1050 nm wavelength was not less than 80%. The specific connecting method was as follows:

[0108] (1) The ceramic parent material and the metal parent material were processed into blocks with a size of 15 x 12 x 2 mm 3 , the connecting surfaces of the two were ground and polished respectively, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the connecting surface of the required yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the connecting surface of the TC4 titanium alloy was ≤5 μm.

[0109] (2) The yttria transparent ceramic after ultrasonic cleaning was placed in a magnetron sputtering sample chamber, the sample chamber was vacuumized to 10 - 1Pa and the transparent ceramic was radio frequency cleaned for 3 min at 80 W power. Then the sputtering chamber was vacuumized and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering chamber reached 6 x 10 -3 Pa, the temperature was raised to 200℃, the Ti target was pre-sputtered for 10 min at 200 W power, then the target shutter and the base rotation switch were opened, the Ti target was magnetron sputtered for 15 min at 220 W power, then the Al target was pre-sputtered for 10 min, the target shutter and the base rotation switch were opened, and the Al target was magnetron sputtered for 20 min at 220 W power.

[0110] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer was combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and was assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and after the vacuum degree in the furnace chamber reached 5 x 10 -3 Pa, the temperature was raised to 900℃, and then an electric field was applied in the direction from the first electrode to the second electrode, and when the current density reached 1 mA / mm 2 , it was maintained for 120 s, and then the temperature was cooled to room temperature at a rate of 3℃ / min, to obtain a yttria transparent ceramic / Ti / Al / TC4 titanium alloy connecting piece.

[0111] The connecting piece prepared in Example 10 was detected by a universal testing machine CLY30, and the shear strength of the connecting piece was 72 MPa, and the thickness of the Ti / Al intermediate layer was 580 nm.

[0112] Example 11

[0113] In this example 11, Cr / Ni was used as a composite intermediate layer to electric field assisted connect yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic at room temperature was ≥160 MPa, the elastic modulus was ≥150 GPa, and the optical transmittance at 1050 nm wavelength was not less than 80%. The specific connecting method was as follows:

[0114] (1) The ceramic and metal parent materials were processed into blocks with a size of 15 x 12 x 2 mm 3 , the surfaces to be connected of the two were ground and polished, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the TC4 titanium alloy was ≤5 μm.

[0115] (2) The yttria transparent ceramic after ultrasonic cleaning was placed in a magnetron sputtering sample chamber, the sample chamber was vacuumized to 10 - 1Pa and the transparent ceramic was radio frequency cleaned for 3 min at 80 W power. Then the sputtering chamber was vacuumized and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering chamber reached 8 x 10 -3 Pa, the temperature was raised to 200℃, the Cr target was pre-sputtered for 10 min at 200 W power, then the target shutter and the base rotation switch were opened, the Cr target was magnetron sputtered for 20 min at 200 W power, then the Ni target was pre-sputtered for 10 min, the target shutter and the base rotation switch were opened, and the Ni target was magnetron sputtered for 20 min at 200 W power.

[0116] (3) The yttria transparent ceramic after the magnetron sputtering of the intermediate layer was combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and was assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and after the vacuum degree in the furnace chamber reached 5 x 10 -3 Pa, the temperature was raised to 900℃, then an electric field was applied in the direction from the first electrode to the second electrode, and when the current density reached 4.5 mA / mm 2 , it was maintained for 30 s, and the temperature was cooled to room temperature at a rate of 3℃ / min, to obtain a yttria transparent ceramic / Cr / Ni / TC4 titanium alloy connecting piece.

[0117] The connecting piece prepared in this embodiment 11 was detected by a universal testing machine CLY30, and the shear strength of the connecting piece was 67 MPa, and the thickness of the Cr / Ni intermediate layer was 700 nm.

[0118] Embodiment 12

[0119] In this embodiment 12, Cr / Al was used as a composite intermediate layer to electric field assisted connect yttria transparent ceramic and TC4 titanium alloy, wherein the bending strength of the yttria transparent ceramic at room temperature was ≥160 MPa, the elastic modulus was ≥150 GPa, and the optical transmittance at 1050 nm wavelength was not less than 80%. The specific connecting method was as follows:

[0120] (1) The ceramic and metal parent materials were processed into blocks with the size of 15 x 12 x 2 mm 3 , the surfaces to be connected of the two were ground and polished, and the impurities and oil stains were removed by ultrasonic cleaning in ethanol solution. The surface roughness Ra of the surface to be connected of the required yttria transparent ceramic was ≤0.1 μm, and the surface roughness Ra of the surface to be connected of the TC4 titanium alloy was ≤5 μm.

[0121] (2) The yttria transparent ceramic after ultrasonic cleaning was placed in a magnetron sputtering sample chamber, the sample chamber was vacuumized to 10 - 1Pa and the transparent ceramic was radio frequency cleaned for 3 min at 80 W power. Then the sputtering chamber was vacuumized and the sample feeding process was carried out. When the vacuum degree of the magnetron sputtering chamber reached 8 x 10 -3 Pa, the temperature was raised to 200°C, the Cr target was pre-sputtered for 10 min at 200 W power, then the target shutter and the base rotation switch were opened, the Cr target was magnetron sputtered for 20 min at 220 W power, then the Al target was pre-sputtered for 10 min, the target shutter and the base rotation switch were opened, and the Al target was magnetron sputtered for 15 min at 220 W power.

[0122] (3) The yttria transparent ceramic after magnetron sputtering of the intermediate layer was combined with the TC4 titanium alloy in the order of electrode / ceramic / intermediate layer / metal / electrode, and was assembled in an electric field assisted diffusion bonding device. An axial pressure of 0.5 MPa was applied to the assembly, and after the vacuum degree in the furnace chamber reached 6 x 10 -3 Pa, the temperature was raised to 900°C, then an electric field was applied in the direction from the first electrode to the second electrode, and when the current density reached 2 mA / mm 2 , it was maintained for 60 s, and the temperature was cooled to room temperature at a cooling rate of 3°C / min, to obtain a yttria transparent ceramic / Cr / Al / TC4 titanium alloy connecting piece.

[0123] The connecting piece joint prepared in this embodiment 12 was detected by a universal testing machine CLY30, and the shear strength of the connecting piece joint was 70 MPa, and the thickness of the Cr / Al intermediate layer was 570 nm.

[0124] Comparative Example 1

[0125] In this comparative example 1, the process of magnetron sputtering of the intermediate layer and electric field assisted rapid connection was referred to embodiment 5, except that the connection time of the electric field assisted rapid connection was extended to 300 s. The obtained yttria transparent ceramic / Ti / TC4 titanium alloy was not connected.

[0126] Comparative Example 2

[0127] In this comparative example 2, the process of magnetron sputtering of the intermediate layer and electric field assisted rapid connection was referred to embodiment 2, except that the current density of the electric field assisted rapid connection was increased to 10 mA / mm 2 . The obtained yttria transparent ceramic / Ni / Monel400 alloy was not connected.

[0128] Comparative Example 3

[0129] In this comparative example 3, the process of magnetron sputtering of the intermediate layer and electric field assisted rapid connection was referred to embodiment 4, except that the magnetron sputtering time was extended to 50 min, and the thickness of the prepared Al soft metal intermediate layer was 950 nm. The obtained yttria transparent ceramic / Al / TC4 titanium alloy was not connected.

[0130] Comparative Example 4

[0131] The magnetron sputtering interlayer and electric field-assisted rapid bonding process in Comparative Example 4 was similar to that in Example 10, except that the magnetron sputtering time was extended to 25 or 35 minutes, and the resulting Ti / Al composite interlayer had a thickness of 1050 nm. However, the resulting yttrium oxide transparent ceramic / Ti / Al / TC4 titanium alloy was not bonded.

[0132] Table 1 lists the thickness of the intermediate layers and the shear strength of the connector joints prepared in Examples 1 to 12 and Comparative Examples 1 to 4.

[0133] Table 1:

[0134]

[0135]

[0136] It can be seen from Table 1 that the strength of the connector with the composite intermediate layer is generally higher than the strength of the connector with a simple intermediate layer, but the specific shear strength still needs to be combined with the process parameters used. The results of Example 4 and Comparative Example 3, and Example 10 and Comparative Example 4 show that too long a magnetron sputtering time causes the intermediate layer to be too thick, which is not conducive to the relief of residual stress and will result in an inability to achieve effective connection. The results of Example 5 and Comparative Example 1 show that the connection strength is affected by the connection time. If the connection time is too long, the reaction will be excessive, and the excess product will make it impossible to achieve connection, which is also not conducive to the relief of residual stress. The results of Example 2 and Comparative Example 2 show that the connection strength is affected by the current density. If the current density is too large, excessive intermetallic compounds will be generated, which is not conducive to the relief of residual stress and effective connection.

Claims

1. A method for alleviating residual stress in electric field-assisted quick connection of yttrium oxide transparent ceramic and metal, characterized in that: include: (1) Using magnetron sputtering to prepare an intermediate layer on the surface to be joined of the yttrium oxide transparent ceramic that has been pre-treated by grinding, polishing and ultrasonic cleaning; The intermediate layer is a composite intermediate layer, and the composite intermediate layer is selected from Ti / Ni, Ti / Al, Cr / Ni or Cr / Al; in the composite intermediate layer, the hard metal intermediate layer Ti and Cr are close to the yttrium oxide transparent ceramic side, and the soft metal intermediate layer Ni and Al are close to the metal side to be connected, so that the thermal expansion coefficient achieves a gradient transition and effectively relieves residual stress; the thickness of the composite intermediate layer is 600-800nm; the thickness of the hard metal intermediate layer in the composite intermediate layer is 300-400nm, and the thickness of the soft metal intermediate layer is 300-400nm; (2) Assemble the sample to be connected in the order of first electrode / yttrium oxide transparent ceramic / intermediate layer / metal / second electrode and place it in the electric field assisted diffusion bonding device. Apply an axial pressure of 0.1 to 1 MPa to the sample to be connected. -3 Pa, heat it to 875-925℃ and apply an electric field to the sample to be connected through the electrode. When the current density reaches 1-5 mA / mm 2 Then, the power is continued to be turned on and the temperature is kept for 30 to 180 seconds, and finally cooled to room temperature at a cooling rate of 3 to 5°C / min to obtain a yttrium oxide transparent ceramic / intermediate layer / metal connecting piece; the metal is one of titanium-based alloy, iron-based alloy or monel alloy.

2. The method according to claim 1, characterized in that The room temperature flexural strength of the yttrium oxide transparent ceramic is ≥150 MPa, the elastic modulus is ≥160 GPa, and the optical transmittance at a wavelength of 1050 nm is not less than 80%.

3. The method according to claim 1, characterized in that The surfaces of the yttrium oxide transparent ceramic and the metal to be connected are ground and polished and ultrasonically cleaned in an ethanol solution to ensure that the surface roughness Ra of the surface of the yttrium oxide transparent ceramic to be connected is less than or equal to 0.1 μm and the surface roughness Ra of the surface of the metal to be connected is less than or equal to 5 μm.

4. The method according to claim 1, wherein The metal includes TC4, 4J29, 4J33 or Monel400.

5. The method according to claim 1, wherein In step (1), the magnetron sputtering method includes: placing the pretreated yttrium oxide transparent ceramic into the magnetron sputtering sample chamber, evacuating the chamber to a vacuum of 0.05-0.1 Pa, and performing radio frequency cleaning on the surface of the yttrium oxide transparent ceramic to be sputtered at a power of 75-85 W for 2-5 minutes; then evacuating the sputtering chamber to a vacuum of 5×10 -3 ~8×10 - 3 Pa and heat to 175-225 ° C, pre-sputter at a power of 200-250 W for 5-10 minutes, then open the target baffle and base rotation switch, and perform magnetron sputtering at a sputtering power of 200-250 W.

6. The method according to claim 1, characterized in that In step (1), the sputtering time of the hard metal intermediate layer in the composite intermediate layer is 15 to 20 minutes, and the sputtering time of the soft metal intermediate layer is 15 to 20 minutes.

7. The method according to claim 1, characterized in that In step (2), the direction of the applied electric field is from the first electrode to the second electrode, that is, from the yttrium oxide transparent ceramic side to the intermediate layer and finally to the metal side.

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