A method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys

Abstract

A method for low-temperature diffusion bonding of zirconium alloys assisted by surface electrolytic hydrogenation relates to a diffusion bonding method for zirconium alloys. This method aims to solve the problems of high temperature in diffusion bonding of zirconium alloys and easy deformation of zirconium alloys after gas-phase hydrogenation. Method: The zirconium alloy is surface-grinded and polished to obtain the zirconium alloy to be hydrogenated, and the zirconium alloy to be hydrogenated is prepared into a surface hydrogenated zirconium alloy by oxidation-reduction using electrolytic hydrogenation. The depth of the hydrogenated layer on the surface of the zirconium alloy is at least 24 μm, forming the parts to be welded for diffusion welding. The surface hydrogenated zirconium alloy prepared by the present invention has excellent mechanical properties, is not easily deformed at high temperatures, and is easy to form a diffusion joint with excellent performance and small deformation.

Description

Technical Field

[0001] The invention relates to a diffusion bonding method for zirconium alloys. Background Art

[0002] Zirconium alloys, with their advantages of low thermal neutron absorption cross-section, high hardness, ductility, and corrosion resistance, are often used in nuclear fuel cladding in pressurized water reactors. However, conventional fusion welding has the disadvantage of exceeding the zirconium alloy's phase transition point, degrading its properties. Furthermore, fusion welding temperatures exceeding the fuel core's phase transition point can prematurely irradiate the zirconium alloy.

[0003] Traditional fusion welding methods require the joint to be molten at high temperatures, with the molten liquid on both sides of the weld mixing and solidifying after cooling to securely weld the two workpieces together. However, in the context of new zirconium alloy cladding applications, since the distance between welds is only less than 2mm, the deformation of the joint after melting is inevitably difficult to control. Furthermore, to melt the zirconium alloy, temperatures greater than ~1850°C are required, which significantly exceeds the phase transition temperature of the zirconium alloy, resulting in reduced cladding performance and increased susceptibility to corrosion and cracking during use. This temperature also significantly exceeds the phase transition point of the fuel core, reducing the irradiation performance of the fuel element.

[0004] Gas phase hydrogenation is a method of placing a metal in a vacuum tube furnace, introducing hydrogen at high temperature, and using gas pressure to introduce a large amount of hydrogen into the material. Since the material's ability to absorb hydrogen at high temperatures will increase significantly, after cooling to room temperature, the hydrogen that exceeds the room temperature absorption capacity will precipitate in the form of hydrides and be evenly distributed within the material. Gas phase hydrogenation was first applied to titanium alloys. People found that the titanium alloys after hydrogenation showed an ability to deform more easily during cutting than before. Subsequently, their microstructures were observed, and it was found that after gas phase hydrogenation, the hydrides would be evenly distributed within the titanium alloy, and the phase transition point of the titanium alloy would be lowered, causing its microstructure to change at room temperature. At present, research on gas phase hydrogenation of zirconium alloys has been relatively extensive. The microstructure of zirconium alloys has an hcp structure, so it is difficult to observe microstructure changes at room temperature after gas phase hydrogenation, but the hydrides are also evenly distributed within the zirconium alloy in a dispersed form, which is consistent with gas phase hydrogenation of titanium alloys.

[0005] The affected area of ​​diffusion bonding is mainly on the surface of the material. After the zirconium alloy is hydrogenated in the gas phase, the hydrides in the zirconium alloy are distributed inside the material and mixed with the zirconium matrix. The interior of the zirconium alloy is full of hydrides. Hydrogen embrittlement has a greater impact on the material as a whole. Although the hardness of the zirconium alloy increases, the plasticity decreases, and it is very easy to crack from the inside. In addition, due to the influence of hydrogen-induced plasticity during the diffusion bonding process, it is very easy to produce large deformation under pressure, which will destroy the welded structure. Summary of the Invention

[0006] In order to solve the problems of high temperature of diffusion bonding of zirconium alloys (the zirconium alloys are Zr-2, Zr-4 and other Zr-Sn alloys) and easy deformation of zirconium alloys after gas phase hydrogenation, the present invention proposes a method for surface electrolytic hydrogenation assisted low-temperature diffusion bonding of zirconium alloys.

[0007] The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys of the present invention is carried out according to the following steps:

[0008] Step 1: Grinding and polishing the surface of the zirconium alloy to obtain the zirconium alloy to be hydrogenated;

[0009] Step 2: Using electrolytic hydrogenation to prepare the zirconium alloy to be hydrogenated prepared in step 1 into a surface hydrogenated zirconium alloy by oxidation-reduction, wherein the thickness of the hydrogenated layer on the surface of the zirconium alloy is at least 24 μm;

[0010] The electrolytic hydrogenation process is as follows: electrolytic hydrogenation is carried out in a water bath with a water bath temperature of 50-70° C. and a current of 0.2-0.8 A / cm 2 , time is 50-70h, electrolyte concentration is 0.3-0.6mol / L, and thiourea concentration in the electrolyte is 2-8g / L;

[0011] Step 3: Remove the oil stains on the surface of the hydrogen-permeated layer of the surface hydrogen-permeated zirconium alloy, place the hydrogen-permeated layers of the surface hydrogen-permeated zirconium alloy opposite to each other and stack them to obtain the parts to be welded, and perform diffusion welding;

[0012] The diffusion welding process is as follows: a heating rate of 5 to 20°C / min, a diffusion welding temperature of 700 to 800°C, an applied pressure of 3 to 10 MPa, and a heat preservation and pressure holding time of 30 to 90 minutes; after the heat preservation and pressure holding is completed, a cooling rate of 5 to 20°C / min is used to cool the temperature to 100 to 200°C.

[0013] The principles and beneficial effects of the present invention are:

[0014] A hydride layer is formed on the surface of the zirconium alloy after electrolytic hydrogenation in the present invention. No obvious hydride appears inside the material and it is mainly a zirconium matrix. Hydrogen embrittlement has almost no effect on the interior of the material, and the overall material properties do not change much. The zirconium matrix will not produce large deformation during the diffusion bonding process, which is more conducive to diffusion bonding.

[0015] In the art, zirconium alloys are corroded by water in pressurized water reactors. Therefore, the current electrolytic hydrogenation method is only used for simulation research on zirconium alloy surface corrosion. The main purpose of the simulation research on zirconium alloy surface corrosion is to focus on the impact of hydrogen embrittlement on the material. Therefore, it is only necessary to generate a hydrogenation layer with a thickness of no more than 10 μm. The present invention uses electrolytic hydrogenation for diffusion bonding. The present invention inserts a surface hydrogenation layer of at least 24 μm into the surface of the zirconium alloy through hydrogenation. A large amount of hydrogen atoms will be completely released as alloying elements, and the diffusion of Zr atoms and the hydrogen-induced plastic deformation effect will promote interface connection during the diffusion bonding process, so that the connection interface can complete good diffusion at low temperature. At the same time, the electrolytic hydrogenation will not remain in the zirconium matrix to cause hydrogen embrittlement. Therefore, the present invention can obtain a connection joint with better performance and a material with good performance after welding.

[0016] In summary, the surface hydrogen-impregnated zirconium alloy prepared by the present invention has excellent mechanical properties, is not easily deformed at high temperatures, and is easy to form a diffusion joint with excellent performance and small deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the microstructure of the zirconium alloy after gas phase hydrogenation (500x); it can be seen that a "window grille"-like microstructure has formed inside the zirconium alloy;

[0018] Figure 2 This is the microstructure of the zirconium alloy after electrolytic hydrogenation;

[0019] Figure 3 This is an enlarged view of the microstructure of the zirconium alloy after electrolytic hydrogenation; Figure 2 and 3 It can be seen that there is no obvious hydride inside the zirconium alloy material.

[0020] Figure 4 This is the room temperature tensile strength curve of the surface hydrogenated zirconium alloy diffusion bonded joint;

[0021] Figure 5 This is the high temperature tensile strength curve of the surface hydrogenated zirconium alloy diffusion bonded joint; DETAILED DESCRIPTION

[0022] The technical solution of the present invention is not limited to the specific implementation methods listed below, but also includes any reasonable combination of the specific implementation methods.

[0023] Specific embodiment 1: The method of surface electrolytic hydrogenation assisted low-temperature diffusion bonding of zirconium alloy in this embodiment is carried out according to the following steps:

[0024] Step 1: Grinding and polishing the surface of the zirconium alloy to obtain the zirconium alloy to be hydrogenated;

[0025] Step 2: Using electrolytic hydrogenation to prepare the zirconium alloy to be hydrogenated prepared in step 1 into a surface hydrogenated zirconium alloy by oxidation-reduction, wherein the thickness of the hydrogenated layer on the surface of the zirconium alloy is at least 24 μm;

[0026] The electrolytic hydrogenation process is as follows: electrolytic hydrogenation is carried out in a water bath with a water bath temperature of 50-70° C. and a current of 0.2-0.8 A / cm 2 , time is 50-70h, electrolyte concentration is 0.3-0.6mol / L, and thiourea concentration in the electrolyte is 2-8g / L;

[0027] Step 3: Remove the oil stains on the surface of the hydrogen-permeated layer of the surface hydrogen-permeated zirconium alloy, place the hydrogen-permeated layers of the surface hydrogen-permeated zirconium alloy opposite to each other and stack them to obtain the parts to be welded, and perform diffusion welding;

[0028] The diffusion welding process is as follows: a heating rate of 5 to 20°C / min, a diffusion welding temperature of 700 to 800°C, an applied pressure of 3 to 10 MPa, and a heat preservation and pressure holding time of 30 to 90 minutes; after the heat preservation and pressure holding is completed, a cooling rate of 5 to 20°C / min is used to cool the temperature to 100 to 200°C.

[0029] This embodiment has the following beneficial effects:

[0030] In this embodiment, a hydride layer is formed on the surface of the zirconium alloy after electrolytic hydrogenation. No obvious hydride appears inside the material and it is mainly a zirconium matrix. Hydrogen embrittlement has almost no effect on the interior of the material, and the overall material properties do not change much. The zirconium matrix will not produce large deformation during the diffusion bonding process, which is more conducive to diffusion bonding.

[0031] In this field, zirconium alloys are corroded by water in pressurized water reactors. Therefore, the current electrolytic hydrogenation method is only used for simulation research on zirconium alloy surface corrosion. The main purpose of the simulation research on zirconium alloy surface corrosion is to focus on the impact of hydrogen embrittlement on materials. Therefore, it is only necessary to generate a hydrogenation layer with a thickness of no more than 10 μm. This embodiment uses electrolytic hydrogenation for diffusion bonding. This embodiment inserts a surface hydrogenation layer of at least 24 μm on the surface of the zirconium alloy. A large amount of hydrogen atoms will be completely released as alloying elements, which promotes the diffusion of Zr atoms and the hydrogen-induced plastic deformation to promote interface connection during the diffusion bonding process, so that the connection interface can complete good diffusion at low temperature. At the same time, electrolytic hydrogenation will not remain in the zirconium matrix to cause hydrogen embrittlement. Therefore, this embodiment can obtain a connection joint with better performance and a material with good performance after welding.

[0032] In summary, the surface hydrogen-impregnated zirconium alloy prepared in this embodiment has excellent mechanical properties, is not easily deformed at high temperatures, and is easy to form a diffusion joint with excellent performance and small deformation.

[0033] Specific embodiment 2: This embodiment differs from specific embodiment 1 in that: the purity of the zirconium alloy in step 1 is a rolled plate with a purity of more than 99.8%; the zirconium alloy is a Zr-Sn alloy such as Zr-2, Zr-4, etc.

[0034] Specific embodiment three: This embodiment differs from specific embodiment one or two in that: the method for surface electrolytic hydrogenation assisted low-temperature diffusion bonding of zirconium alloy according to claim 1 is characterized in that: the solvent of the electrolyte in step two is deionized water, and the solute is concentrated sulfuric acid.

[0035] Specific embodiment 4: This embodiment differs from specific embodiment 3 in that the mass fraction of the concentrated sulfuric acid is 98%.

[0036] The diffusion welding process is as follows: a heating rate of 5 to 20°C / min, a diffusion welding temperature of 700 to 800°C, an applied pressure of 3 to 10 MPa, and a heat preservation and pressure holding time of 30 to 90 minutes; after the heat preservation and pressure holding is completed, a cooling rate of 5 to 20°C / min is used to cool the temperature to 100 to 200°C.

[0037] Specific embodiment five: The difference between this embodiment and any one of specific embodiments one to four is that the diffusion welding process described in step three is: the heating rate is 5 to 20°C / min, the diffusion welding temperature is 700 to 800°C, the applied pressure is 3 to 10 MPa, and the insulation and pressure holding time is 30 to 90 minutes; after the insulation and pressure holding is completed, the cooling rate is 5 to 20°C / min, and the temperature is cooled to 150°C.

[0038] Specific embodiment six: The difference between this embodiment and any one of specific embodiments one to five is that the diffusion welding process described in step three is: the heating rate is 15°C / min, the diffusion welding temperature is 700-800°C, the applied pressure is 3-10MPa, and the insulation and pressure holding time is 30-90min; after the insulation and pressure holding is completed, the cooling rate is 5-20°C / min, and the temperature is cooled to 100-200°C.

[0039] Specific embodiment seven: The difference between this embodiment and any one of specific embodiments one to six is ​​that the diffusion welding process described in step three is: the heating rate is 5 to 20°C / min, the diffusion welding temperature is 750°C, the applied pressure is 3 to 10 MPa, and the insulation and pressure holding time is 30 to 90 minutes; after the insulation and pressure holding is completed, the cooling rate is 5 to 20°C / min, and the temperature is cooled to 100 to 200°C.

[0040] Specific embodiment eight: The difference between this embodiment and any one of specific embodiments one to seven is that the diffusion welding process described in step three is: the heating rate is 5 to 20°C / min, the diffusion welding temperature is 700 to 800°C, the applied pressure is 6MPa, and the insulation and pressure holding time is 30 to 90min; after the insulation and pressure holding is completed, the cooling rate is 5 to 20°C / min, and the temperature is cooled to 100 to 200°C.

[0041] Specific embodiment nine: The difference between this embodiment and any one of specific embodiments one to eight is that the diffusion welding process described in step three is: the heating rate is 5 to 20°C / min, the diffusion welding temperature is 700 to 800°C, the applied pressure is 3 to 10 MPa, and the insulation and pressure holding time is 45 minutes; after the insulation and pressure holding is completed, the cooling rate is 5 to 20°C / min, and the temperature is cooled to 100 to 200°C.

[0042] Specific embodiment ten: The difference between this embodiment and any one of specific embodiments one to nine is that the diffusion welding process described in step three is: the heating rate is 5 to 20°C / min, the diffusion welding temperature is 700 to 800°C, the applied pressure is 3 to 10 MPa, and the insulation and pressure holding time is 30 to 90 minutes; after the insulation and pressure holding is completed, the cooling rate is 10°C / min, and the temperature is cooled to 100 to 200°C.

[0043] Example 1

[0044] The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys in this embodiment is carried out in the following steps:

[0045] Step 1: Grinding and polishing the surface of the zirconium alloy to obtain the zirconium alloy to be hydrogenated;

[0046] The zirconium alloy is a rolled plate with a purity of more than 99.8%; the zirconium alloy is Zr-4.

[0047] Step 2: Using electrolytic hydrogenation to prepare the hydrogenated zirconium alloy prepared in step 1 into a surface hydrogenated zirconium alloy by oxidation-reduction;

[0048] The electrolytic hydrogenation process is as follows: electrolytic hydrogenation is carried out in a water bath with a water bath temperature of 60° C. and a current of 0.30 A / cm 2 , time is 45h, electrolyte concentration is 0.45mol / L; thiourea concentration in the electrolyte is 4g / L;

[0049] The solvent of the electrolyte is deionized water, the solute is concentrated sulfuric acid, and the mass fraction of the concentrated sulfuric acid is 98%;

[0050] Step 3: Remove the oil stains on the surface of the hydrogen-permeated layer of the surface hydrogen-permeated zirconium alloy, place the hydrogen-permeated layers of the surface hydrogen-permeated zirconium alloy opposite to each other and stack them to obtain the parts to be welded, and perform diffusion welding;

[0051] The diffusion welding process is as follows: a heating rate of 15°C / min, a diffusion welding temperature of 750°C, an applied pressure of 6 MPa, and a heat preservation and pressure holding time of 45 minutes; after the heat preservation and pressure holding is completed, the cooling rate is 10°C / min, and the temperature is lowered to 150°C.

[0052] Figure 1 This is a microstructure image of a zirconium alloy after vapor-phase hydrogenation (500x); a "window-patterning" microstructure can be seen within the zirconium alloy. The vapor-phase hydrogenation process involves placing the metal in a vacuum tube furnace and introducing hydrogen at 700°C for 135 minutes, with a hydrogen dosage of 0.3 wt.%. The zirconium alloy measures 55×55×3.5 mm. Because the material's ability to absorb hydrogen increases significantly at high temperatures, any excess hydrogen, after cooling to room temperature, precipitates as hydrides, evenly distributed throughout the material.

[0053] Figure 2 The microstructure of zirconium alloy after electrolytic hydrogenation is shown in Figure 2. Figure 3 This is an enlarged view of the microstructure of the zirconium alloy after electrolytic hydrogenation. Figure 2 and 3 It can be seen that there is no obvious hydride inside the zirconium alloy material, and a 24μm surface hydrogen permeation layer is formed on the surface of the zirconium alloy. Figure 4 This is the room temperature tensile strength curve of the surface hydrogenated zirconium alloy diffusion bonded joint. Figure 5 This is a high-temperature tensile strength curve of the surface hydrogenated zirconium alloy diffusion bonded joint; the tensile strength of the joint reaches 92% of the parent material strength at room temperature and 90% of the parent material strength at a high temperature of 350°C.

[0054] Example 2

[0055] The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys in this embodiment is carried out in the following steps:

[0056] Step 1: Grinding and polishing the surface of the zirconium alloy to obtain the zirconium alloy to be hydrogenated;

[0057] The zirconium alloy is a rolled plate with a purity of more than 99.8%; the zirconium alloy is Zr-4.

[0058] Step 2: Using electrolytic hydrogenation to prepare the hydrogenated zirconium alloy prepared in step 1 into a surface hydrogenated zirconium alloy by oxidation-reduction;

[0059] The electrolytic hydrogenation process is as follows: electrolytic hydrogenation is carried out in a water bath with a water bath temperature of 55°C and a current of 0.80A / cm 2, time is 50h, electrolyte concentration is 0.6mol / L, thiourea concentration in the electrolyte is 6g / L; the solvent of the electrolyte is deionized water, the solute is concentrated sulfuric acid, and the mass fraction of concentrated sulfuric acid is 98%;

[0060] Step 3: Remove the oil stains on the surface of the hydrogen-permeated layer of the surface hydrogen-permeated zirconium alloy, place the hydrogen-permeated layers of the surface hydrogen-permeated zirconium alloy opposite to each other and stack them to obtain the parts to be welded, and perform diffusion welding;

[0061] The diffusion welding process is as follows: a heating rate of 15°C / min, a diffusion welding temperature of 750°C, an applied pressure of 6 MPa, and a heat preservation and pressure holding time of 45 minutes; after the heat preservation and pressure holding is completed, the cooling rate is 10°C / min, and the temperature is lowered to 150°C.

[0062] In this embodiment, the thickness of the hydrogen permeation layer on the surface of the zirconium alloy is 24 μm; the tensile strength of the joint is 403 MPa at room temperature, and the tensile strength of the joint is 173 MPa at a high temperature of 350°C.

[0063] Example 3

[0064] The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys in this embodiment is carried out in the following steps:

[0065] Step 1: Grinding and polishing the surface of the zirconium alloy to obtain the zirconium alloy to be hydrogenated;

[0066] The zirconium alloy is a rolled plate with a purity of more than 99.8%; the zirconium alloy is Zr-4.

[0067] Step 2: Using electrolytic hydrogenation to prepare the hydrogenated zirconium alloy prepared in step 1 into a surface hydrogenated zirconium alloy by oxidation-reduction;

[0068] The electrolytic hydrogenation process is as follows: electrolytic hydrogenation is carried out in a water bath with a water bath temperature of 70°C and a current of 0.20A / cm 2 , time is 70h, electrolyte concentration is 0.4mol / L, and thiourea concentration in the electrolyte is 8g / L;

[0069] The solvent of the electrolyte is deionized water, the solute is concentrated sulfuric acid, and the mass fraction of the concentrated sulfuric acid is 98%;

[0070] Step 3: Remove the oil stains on the surface of the hydrogen-permeated layer of the surface hydrogen-permeated zirconium alloy, place the hydrogen-permeated layers of the surface hydrogen-permeated zirconium alloy opposite to each other and stack them to obtain the parts to be welded, and perform diffusion welding;

[0071] The diffusion welding process is as follows: a heating rate of 15°C / min, a diffusion welding temperature of 750°C, an applied pressure of 6 MPa, and a heat preservation and pressure holding time of 45 minutes; after the heat preservation and pressure holding is completed, the cooling rate is 10°C / min, and the temperature is lowered to 150°C.

[0072] In this embodiment, the thickness of the hydrogen permeation layer on the surface of the zirconium alloy is 24 μm; the tensile strength of the joint is 403 MPa at room temperature, and the tensile strength of the joint is 173 MPa at a high temperature of 350°C.

Claims

1. A method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys, characterized in that: The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys is carried out in the following steps: Step 1: Grinding and polishing the surface of the zirconium alloy to obtain the zirconium alloy to be hydrogenated; Step 2: Using electrolytic hydrogenation to prepare the zirconium alloy to be hydrogenated prepared in step 1 into a surface hydrogenated zirconium alloy by oxidation-reduction, wherein the thickness of the hydrogenated layer on the surface of the zirconium alloy is at least 24 μm; The electrolytic hydrogenation process is as follows: electrolytic hydrogenation is carried out in a water bath with a water bath temperature of 50-70° C. and a current of 0.2-0.8 A / cm 2 , time is 50-70h, electrolyte concentration is 0.3-0.6mol / L, and thiourea concentration in the electrolyte is 2-8g / L; The solvent of the electrolyte in step 2 is deionized water, and the solute is concentrated sulfuric acid; the mass fraction of the concentrated sulfuric acid is 98%; Step 3: Remove the oil stains on the surface of the hydrogen-permeated layer of the surface hydrogen-permeated zirconium alloy, place the hydrogen-permeated layers of the surface hydrogen-permeated zirconium alloy opposite to each other and stack them to obtain the parts to be welded, and perform diffusion welding; The diffusion welding process is as follows: a heating rate of 5 to 20°C / min, a diffusion welding temperature of 700 to 800°C, an applied pressure of 3 to 10 MPa, and a heat and pressure holding time of 30 to 90 minutes; After the heat preservation and pressure holding is completed, the cooling rate is 5-20℃ / min, and the temperature is reduced to 100-200℃.

2. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: In step 1, the purity of the zirconium alloy is a rolled plate of more than 99.8%, and the zirconium alloy is Zr-2 or Zr-4.

3. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: The diffusion welding process in step 3 is as follows: a heating rate of 5 to 20°C / min, a diffusion welding temperature of 700 to 800°C, an applied pressure of 3 to 10 MPa, and a heat and pressure holding time of 30 to 90 minutes; After the heat preservation and pressure holding is completed, the cooling rate is 5-20℃ / min, and the temperature is reduced to 150℃.

4. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: The diffusion welding process in step three is as follows: the heating rate is 15°C / min, the diffusion welding temperature is 700-800°C, the applied pressure is 3-10 MPa, and the insulation and pressure holding time is 30-90 min; after the insulation and pressure holding is completed, the cooling rate is 5-20°C / min, and the temperature is lowered to 100-200°C.

5. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: The diffusion welding process in step three is as follows: the heating rate is 5-20°C / min, the diffusion welding temperature is 750°C, the applied pressure is 3-10 MPa, and the insulation and pressure holding time is 30-90 min; after the insulation and pressure holding is completed, the cooling rate is 5-20°C / min, and the temperature is lowered to 100-200°C.

6. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: The diffusion welding process in step three is as follows: the heating rate is 5-20°C / min, the diffusion welding temperature is 700-800°C, the applied pressure is 6MPa, and the heat preservation and pressure holding time is 30-90min; after the heat preservation and pressure holding is completed, the cooling rate is 5-20°C / min, and the temperature is cooled to 100-200°C.

7. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: The diffusion welding process in step three is as follows: the heating rate is 5-20°C / min, the diffusion welding temperature is 700-800°C, the applied pressure is 3-10 MPa, and the heat preservation and pressure holding time is 45 minutes; after the heat preservation and pressure holding is completed, the cooling rate is 5-20°C / min, and the temperature is cooled to 100-200°C.

8. The method for surface electrolytic hydrogenation-assisted low-temperature diffusion bonding of zirconium alloys according to claim 1, characterized in that: The diffusion welding process in step 3 is as follows: a heating rate of 5 to 20°C / min, a diffusion welding temperature of 700 to 800°C, an applied pressure of 3 to 10 MPa, and a heat and pressure holding time of 30 to 90 minutes; After the heat preservation and pressure holding is completed, the cooling rate is 10℃ / min, and the temperature is reduced to 100-200℃.

Images