High-irradiation shielding granular material and preparation method thereof

Abstract

The invention discloses a high-irradiation shielding granular material and a preparation method thereof, and belongs to the technical field of shielding materials. The invention aims to solve the problems that the existing radiation shielding material cannot have the gamma ray shielding performance, good flexibility, convenient constructability and the like. The particle material is composed of glass microspheres, a chemical nickel-plating layer, an electroplated lead layer, an electroplated tungsten layer and an electroplated tantalum layer. And the thickness of each layer is controlled to be 20 microns. According to the method, nickel is deposited on the surfaces of glass microspheres through a chemical nickel plating method, and then an electroplating lead layer, an electroplating tungsten layer and an electroplating tantalum layer are sequentially deposited through an electroplating method. The glass microspheres are pretreated, and nickel is deposited on the surfaces of the glass microspheres by using a chemical nickel plating method, so that other electroplated layers can be deposited on the surfaces of the glass microspheres more easily; wherein the electroplated lead layer and the electroplated tungsten layer have the characteristic of good gamma ray and neutron composite shielding performance; the metal tantalum layer has good gamma ray shielding performance and excellent mechanical property.

Description

Technical Field

[0001] The invention belongs to the technical field of shielding materials and relates to a high-irradiation shielding granular material and a preparation method thereof. Background Art

[0002] High gamma-ray shielding composite materials play an indispensable protective role in specific places such as hospitals and power stations, and high gamma-ray shielding particles are the basis of shielding composite materials. The design of new shielding particles is of great significance. Traditional gamma-ray radiation shielding materials include glass, concrete and other materials. For current gamma-ray shielding materials, their shielding performance against rays is always limited, and often in the actual ray penetration process, there are multiple rays coexisting. The LBL (layer-by-layer self-assembly) method is used to construct a nano-shielding film on the surface of hollow glass microspheres, which can reduce the density of the shielding material and the sedimentation of the filler powder during the preparation process, and realize the controllable preparation of the multi-layer gradient structure, and improve the ray shielding effect through multi-interface reflection / scattering. Summary of the invention

[0003] The purpose of the present invention is to solve the problems that existing radiation shielding materials cannot have both gamma ray shielding performance, good flexibility and convenient construction, and to provide a high-irradiation shielding granular material and a preparation method thereof. The composite material has excellent high-energy ray shielding performance, good construction performance and versatility, a simple preparation process, low cost, easy operation and good performance.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0005] A high-irradiation shielding granular material consists of glass microspheres, a chemical nickel-plated layer, an electroplated lead layer, an electroplated tungsten layer and an electroplated tantalum layer.

[0006] Furthermore, the thickness of each layer is controlled at 20 μm.

[0007] A method for preparing the above-mentioned high-irradiation shielding granular material, the method comprising: depositing nickel on the surface of glass microspheres by chemical nickel plating, and then sequentially depositing an electroplated lead layer, an electroplated tungsten layer and an electroplated tantalum layer by electroplating.

[0008] Furthermore, the method is:

[0009] Step 1: After pretreatment such as pickling, the glass microspheres are immersed in a nickel sulfate plating solution, and the nickel ions in the plating solution are reduced to metallic nickel on the surface of the glass microspheres and deposited on the glass microspheres to form a plating layer, which is then washed to remove residual impurities;

[0010] Step 2: Place the lead plate in an aqueduct at an angle and connect it to an electrode as a cathode, prepare a basic lead carbonate electroplating solution, and then roll the glass microspheres that have been chemically nickel-plated in step 1 down along the lead plate to allow the reduced lead ions to be evenly deposited on its surface, and then wash it to remove residual impurities;

[0011] Step 3: Place the tungsten plate in the aqueduct at an angle and connect it to the electrode as the cathode, prepare the sodium tungstate electroplating solution, and then roll the glass microspheres that have been electroplated with nickel and lead in step 2 down along the lead plate to make the reduced tungsten ions evenly deposited on its surface, and then clean it to remove the residual impurities;

[0012] Step 4: Place the tantalum plate at an angle in the aqueduct and connect it to the electrode as the cathode, prepare sodium tantalum fluoride electroplating solution, and then roll the glass microspheres that have been electroplated with chemical nickel, lead, and tungsten in step 3 down the lead plate to allow the reduced tantalum ions to be evenly deposited on its surface, and then clean it to remove residual impurities.

[0013] Furthermore, the method also includes step five: in step two, step three or step four, repeating this step once or multiple times to obtain one or more layers of nickel, tungsten or tantalum, and finally preparing a heterogeneous multilayer core-shell structured microsphere radiation shielding composite material.

[0014] Furthermore, in step 1, the concentration of the nickel sulfate plating solution is 100-150 g·L -1 , pH is 5-5.5, cathode current density is 0.5-1A·dm -2 .

[0015] Furthermore, in step 2, the concentration of the basic lead carbonate electroplating solution is 130-150 g·L -1 .

[0016] Furthermore, in step 3, the concentration of the sodium tungstate electroplating solution is 160-210 g·L -1 .

[0017] Furthermore, in step 4, the concentration of the sodium tantalum fluoride electroplating solution is 180-220 g·L -1 .

[0018] The beneficial effects of the present invention compared with the prior art are as follows: the heterogeneous multilayer core-shell structure microsphere radiation shielding composite material in the present invention is composed of glass microspheres, chemical nickel plating layer, electroplated lead layer, electroplated tungsten layer and electroplated tantalum layer. Since the surface of the glass microsphere is smooth, it is difficult to deposit the shielding layer directly on the surface, so the surface needs to be pretreated first, and nickel is deposited on the surface by chemical nickel plating, so that other electroplated layers can be deposited on the surface more easily; the electroplated lead layer and the electroplated tungsten layer have good composite shielding performance of gamma rays and neutrons; the metal tantalum layer has good gamma ray shielding performance and excellent mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the preparation of high radiation shielding granular materials;

[0020] Figure 2 This is a HVL schematic diagram of the shielding material of Example 1;

[0021] Figure 3 This is a TVL schematic diagram of the shielding material of Example 1;

[0022] Figure 4 This is a schematic diagram of the RPE of the shielding material of Example 1;

[0023] Figure 5 It is a HVL schematic diagram of the shielding material of Example 2;

[0024] Figure 6 It is a TVL schematic diagram of the shielding material of Example 2;

[0025] Figure 7 Schematic diagram of RPE of shielding material in Example 2. DETAILED DESCRIPTION

[0026] The technical scheme of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the protection scope of the present invention. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0027] Embodiment 1:

[0028] The functional layer of the multi-layer glass microsphere shielding composite material is divided into four layers, the first layer is a metal nickel layer, the second layer is a metal lead layer, the third layer is a metal tungsten layer, and the fourth layer is a metal tantalum layer.

[0029] After acid washing and other pretreatment, the glass microspheres are immersed in a nickel sulfate plating solution. The nickel ions in the plating solution are reduced to metallic nickel on the surface of the glass microspheres and deposited on the sample to form a coating. The temperature is 50-70°C, and the glass microsphere @ nickel structure is finally prepared. After the experiment is completed, the material is taken out of the plating tank and cleaned to remove residual impurities.

[0030] The lead plate is tilted in the electrolytic cell and connected to the electrode as the cathode. When the glass microsphere @ nickel ball rolls down the inclined plate, the lead ions in the electroplating solution will form a coating on the surface of the glass microsphere @ nickel ball under the action of the electric field, with a current density of 1-3A / dm 2 The electroplating temperature is 25-60°C, and the glass microsphere @ nickel @ lead structure is finally prepared. After the electroplating is completed, the material is taken out of the electroplating tank and cleaned to remove the residual electrolyte and impurities.

[0031] The tungsten plate is tilted in the electrolytic cell and connected to the electrode as the cathode. When the glass microsphere @ nickel @ lead ball rolls down the inclined plate, the tungsten ions in the electroplating solution will form a coating on the surface of the glass microsphere @ nickel @ lead ball under the action of the electric field. The current density is 1-2A / dm 2 The electroplating temperature is 25-60°C, and the glass microsphere @ nickel @ lead @ tungsten structure is finally prepared. After the electroplating is completed, the material is taken out of the electroplating tank and cleaned to remove the residual electrolyte and impurities.

[0032] The tantalum plate is tilted in the electrolytic cell and connected to the electrode as the cathode. When the glass microsphere @ nickel @ lead @ tungsten ball rolls down the inclined plate, the tantalum ions in the electroplating solution will form a coating on the surface of the glass microsphere @ nickel @ lead @ tungsten ball under the action of the electric field, with a current density of 1-2A / dm 2 The electroplating temperature is 450-500°C, and the glass microsphere @ nickel @ lead @ tungsten @ tantalum structure is finally prepared. After the electroplating is completed, the material is taken out of the electroplating tank and cleaned to remove residual electrolyte and impurities.

[0033] The important parameters of gamma ray shielding are half value layer (HVL), tenth value layer (TVL) and mean free path (MFP). HVL (cm) is the parameter of the material thickness required to reduce the initial radiation intensity to half the value, TVL (cm) is the parameter of the material thickness required to reduce the initial radiation intensity to one tenth the value, and MFP (%) is the radiation shielding efficiency. In order to verify the advantages of shielding materials for gamma ray shielding, the present invention experimentally obtained some gamma ray shielding parameters of shielding materials and shielding parameters of comparison groups of the same thickness (lead, tantalum and tungsten). It can be observed from the accompanying drawings of Example 1 that whether it is HVL or TVL data, the shielding material is the lowest, indicating that the thickness of the shielding material required to reduce the initial radiation intensity to a specific value is the smallest. In addition, the RPE value of the shielding material is also the highest, indicating that its radiation shielding efficiency is the best. All of the above illustrate the advantages of the shielding performance of the shielding material.

[0034] Embodiment 2:

[0035] The functional layer of the multi-layer glass microsphere shielding composite material is divided into four layers, the first layer is a metal nickel layer, the second layer is a metal lead layer, the third, fourth and fifth layers are metal tungsten layers, and the sixth, seventh and eighth layers are metal tantalum layers.

[0036] After pretreatment such as pickling, the glass microspheres are immersed in a nickel sulfate plating solution. The nickel ions in the plating solution are reduced to metallic nickel on the surface of the glass microspheres and deposited on the sample to form a plating layer. The temperature is 50-70°C, and the glass microsphere @ nickel structure is finally prepared. After the electroplating is completed, the material is removed from the plating tank and cleaned to remove residual impurities.

[0037] The lead plate is tilted in the electrolytic cell and connected to the electrode as the cathode. When the glass microsphere @ nickel ball rolls down the inclined plate, the lead ions in the electroplating solution will form a coating on the surface of the glass microsphere @ nickel ball under the action of the electric field, with a current density of 1-3A / dm 2 , the electroplating temperature is 18-30°C, and the glass microsphere @ nickel @ lead structure is finally prepared. After the electroplating is completed, the material is taken out of the electroplating tank and cleaned to remove the residual electrolyte and impurities.

[0038] The tungsten plate is tilted in the electrolytic cell and connected to the electrode as the cathode. When the glass microsphere @ nickel @ lead ball rolls down the inclined plate, the tungsten ions in the electroplating solution will form a coating on the surface of the glass microsphere @ nickel @ lead ball under the action of the electric field. The current density is 1-2A / dm 2 The electroplating temperature is 25-60°C, and the step is repeated three times to finally prepare a glass microsphere @ nickel @ lead @ tungsten 3 structure. After the electroplating is completed, the material is taken out of the electroplating tank and cleaned to remove residual electrolyte and impurities.

[0039] The tantalum plate is tilted in the electrolytic cell and connected to the electrode as the cathode. When the glass microsphere @ nickel @ lead @ lead ball rolls down the inclined plate, the tantalum ions in the electroplating solution will form a coating on the surface of the glass microsphere @ nickel @ lead @ lead ball under the action of the electric field, with a current density of 1-2A / dm 2 The electroplating temperature is 400-450°C, and the step is repeated three times to finally prepare a glass microsphere @ nickel @ lead @ tungsten 3 @ tantalum 3 structure. After the electroplating is completed, the material is taken out of the electroplating tank and cleaned to remove residual electrolyte and impurities.

[0040] The important parameters of gamma ray shielding are half value layer (HVL), tenth value layer (TVL) and mean free path (MFP). HVL (cm) is the parameter of the material thickness required to reduce the initial radiation intensity to half the value, TVL (cm) is the parameter of the material thickness required to reduce the initial radiation intensity to one tenth the value, and MFP (%) is the radiation shielding efficiency. In order to verify the advantages of shielding materials for gamma ray shielding, the present invention experimentally obtained some gamma ray shielding parameters of shielding materials and shielding parameters of comparison groups of the same thickness (lead, tantalum and tungsten). It can be observed from the accompanying drawings of Example 1 that whether it is HVL or TVL data, the shielding material is the lowest, indicating that the thickness of the shielding material required to reduce the initial radiation intensity to a specific value is the smallest. In addition, the RPE value of the shielding material is also the highest, indicating that its radiation shielding efficiency is the best. All of the above illustrate the advantages of the shielding performance of the shielding material.

Claims

1. A high radiation shielding granular material, characterized in that: The particle material consists of glass microspheres, a chemically plated nickel layer, an electroplated lead layer, an electroplated tungsten layer and an electroplated tantalum layer.

2. The high radiation shielding granular material according to claim 1, characterized in that: The thickness of each layer is controlled at 20 μm.

3. A method for preparing the high-irradiation shielding granular material according to claim 1 or 2, characterized in that: The method comprises the following steps: depositing nickel on the surface of the glass microspheres by a chemical nickel plating method, and then sequentially depositing an electroplated lead layer, an electroplated tungsten layer and an electroplated tantalum layer by an electroplating method.

4. The method for preparing the high-irradiation shielding granular material according to claim 3, characterized in that: The method is: Step 1: After pretreatment such as pickling, the glass microspheres are immersed in a nickel sulfate plating solution, and the nickel ions in the plating solution are reduced to metallic nickel on the surface of the glass microspheres and deposited on the glass microspheres to form a plating layer, which is then washed to remove residual impurities; Step 2: Place the lead plate in an aqueduct at an angle and connect it to an electrode as a cathode, prepare a basic lead carbonate electroplating solution, and then roll the glass microspheres that have been chemically nickel-plated in step 1 down along the lead plate to allow the reduced lead ions to be evenly deposited on its surface, and then wash it to remove residual impurities; Step 3: Place the tungsten plate in the aqueduct at an angle and connect it to the electrode as the cathode, prepare the sodium tungstate electroplating solution, and then roll the glass microspheres that have been electroplated with nickel and lead in step 2 down along the lead plate to make the reduced tungsten ions evenly deposited on its surface, and then clean it to remove the residual impurities; Step 4: Place the tantalum plate at an angle in the aqueduct and connect it to the electrode as the cathode, prepare sodium tantalum fluoride electroplating solution, and then roll the glass microspheres that have been electroplated with chemical nickel, lead, and tungsten in step 3 down the lead plate to allow the reduced tantalum ions to be evenly deposited on its surface, and then clean it to remove residual impurities.

5. The method for preparing a high-irradiation shielding granular material according to claim 4, characterized in that: The method also includes step five: repeating the step one or more times in step two, step three or step four to obtain one or more layers of nickel, tungsten or tantalum, and finally preparing a heterogeneous multilayer core-shell structured microsphere radiation shielding composite material.

6. The method for preparing a high-irradiation shielding granular material according to claim 4 or 5, characterized in that: In step 1, the concentration of the nickel sulfate plating solution is 100-150g·L -1 , pH is 5-5.5, cathode current density is 0.5-1A·dm -2 .

7. The method for preparing a high-irradiation shielding granular material according to claim 4 or 5, characterized in that: In step 2, the concentration of the basic lead carbonate electroplating solution is 130-150 g·L -1 .

8. The method for preparing a high-irradiation shielding granular material according to claim 4 or 5, characterized in that: In step 3, the concentration of the sodium tungstate electroplating solution is 160-210 g·L -1 .

9. The method for preparing a high-irradiation shielding granular material according to claim 4 or 5, characterized in that: In step 4, the concentration of the sodium tantalum fluoride electroplating solution is 180-220 g·L -1 .

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