Glass scintillator with high neutron detection efficiency and high light yield and preparation method and application thereof

Abstract

The invention discloses a glass scintillator with high photon detection efficiency and high light yield, and a preparation method and application thereof, and belongs to the technical field of scintillator materials. The scintillator comprises a main component and a reducing agent. The main body component comprises the following components in percentage by mass: 40-60% of SiO2, 10-22% of Li2O, 4-10% of Al2O3, 4-12% of CeO2, 2-10% of MgO and 0-25% of XFn, X is one or more of alkaline metal, alkaline earth metal, boron group and rare earth, and XFn is not equal to 0. The scintillation performance of the neutron detection glass scintillator is improved through component regulation and control, the light yield reaches up to 8000ph / MeV and reaches the BGO commercial crystal level, and the energy resolution is 1t; the neutron gamma misjudgment rate is smaller than or equal to 14%, and the neutron detection efficiency is larger than or equal to 95%. The glass scintillator is free of micro-bubbles inside, good in uniformity, high in product yield and good in batch stability, and has an application prospect in the field of neutron detection.

Description

Technical Field

[0001] The invention belongs to the technical field of scintillator materials, and in particular relates to a glass scintillator with high neutron detection efficiency and high light yield, and a preparation method and application thereof. Background Art

[0002] Neutron detection technology has wide application value in many fields such as high-energy physics, atomic energy and medicine. The core of neutron detectors lies in scintillator materials. Scintillator materials, as a luminescent material, can absorb high-energy rays such as gamma rays, x-rays and neutrons, and convert these energies into visible photons. Traditional neutron detectors mostly use gas scintillators or crystal scintillators. These scintillators generally use isotopes with large absorption cross-sections for neutrons as sensitive components, such as 3 He, 6 Li, 10 B and 157 Gd, etc., but in practical applications, it is mainly used 6 Li and 10 B isotope acts as a neutron absorber. Gas scintillator has certain limitations in neutron detection, such as relatively low detection efficiency and easy performance degradation in high-energy neutrons or strong radiation environments. Although crystal scintillator has a high detection efficiency, its preparation process is complicated and the cost is high. Glass scintillator, as a new type of scintillator material, has gradually attracted people's attention. Glass scintillator has excellent properties such as non-deliquescent, acid and alkali resistance, high and low temperature resistance, and can maintain stable detection performance in harsh environments. In addition, the preparation process of glass scintillator is relatively simple and the cost is low. At present, the most widely used glass scintillator for neutron detection is lithium glass of the commercial grade GS series, such as GS20, which is an enriched 6 Li's Ce 3+ Doped lithium aluminosilicate oxide glass.

[0003] At present, the preparation temperature of neutron detection glass based on lithium aluminum silicate oxide is above 1550℃. The viscosity of glass liquid is relatively high at high temperature, and micro bubbles and streaks are easily generated during the preparation process. At the same time, high temperature preparation also has Ce 3+ Problems such as difficulty in controlling ion valence state lead to poor batch stability and low yield rate of products. 3+ It is difficult for the ion valence state to remain single and stable, resulting in a low light yield of the glass scintillator, which in turn affects the neutron and gamma discrimination capabilities, causing neutron and gamma misjudgment. 3+ Ionic valence, carbon powder and other substances are often added to the glass mixture as a reducing agent. However, the introduction of reducing agents can easily cause glass coloring at high temperatures, resulting in a serious decrease in the transmittance of the glass in the visible light band, seriously affecting the performance of the scintillator, and also bringing about problems such as unstable glass quality, which has brought obstacles to the practical application of the product.

[0004] At present, there are not many patents related to scintillating microcrystalline glass. Chinese patent CN100526244C discloses a glass scintillator and its preparation method and thermal neutron detection method, which have high luminous efficiency and thermal neutron detection efficiency of about 90%. However, due to its complicated preparation steps, it needs to use a platinum crucible for secondary melting, and the preparation temperature is high and the insulation time is long, which greatly increases the production energy consumption. Chinese patent CN114133137A discloses a neutron detection glass scintillator and its preparation method and application, which has the characteristics of one-time melting and molding, and provides a strong reducing atmosphere by using a graphite crucible, but the color of the obtained glass is transparent light gray, which will affect the scintillation performance of the glass. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention proposes a glass scintillator with high neutron detection efficiency and high light yield and its preparation method and application. The first technical problem solved by the present invention is to provide a glass scintillator with high neutron detection efficiency and high light yield, which is a new type of Ce 3+ Compared with commercial neutron detection glasses based on lithium aluminum silicate oxide, such as GS20, Ce 3+ Doped fluorosilicate neutron detection glass has higher Li + Ion doping concentration helps to improve the efficiency of neutron detection. And due to the introduction of fluoride, the ultraviolet absorption cutoff edge of the glass is blue-shifted, the transmittance of the glass at short wavelengths is increased, the self-absorption of the scintillator material is reduced, and the light yield of the glass is greatly increased. 3+ The special network structure of doped fluorosilicate neutron detection glass can effectively increase Ce 3+ Solubility of ions, avoid Ce 3+ Ion clusters help increase Ce 3+ Luminous intensity and light yield of glass.

[0006] The second technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned glass scintillator with high neutron detection efficiency and high light yield. In the preparation method, a reducing atmosphere is introduced into the atmosphere furnace to provide a stable strong reducing atmosphere for the glass body, and a glass scintillator with no microbubbles and good uniformity can be prepared at a lower preparation temperature without using a platinum crucible, achieving one-time molding, and preparing a glass scintillator with no bubbles and good uniformity, saving a lot of production costs and effectively ensuring the stability of the product. In addition, another aspect of the present invention is to provide a low-temperature melted neutron detection glass. Compared with traditional lithium aluminum silicate oxide glass, Ce 3+ Doped fluorosilicate neutron detection glass has a lower melting temperature and lower glass liquid viscosity, which helps to obtain glass products with good performance, high yield and good batch stability.

[0007] The third technical problem to be solved by the present invention is to provide the application of the above-mentioned glass scintillator with high neutron detection efficiency and high light yield, based on the high neutron detection efficiency and high light yield glass scintillator having high Ce 3+ Ion doping concentration, high light yield (up to 8000ph / MeV) for 662keV gamma light, excellent energy resolution (<16%), light yield up to 11000ph / n for thermal neutrons, excellent neutron gamma resolution, neutron gamma misjudgment rate ≤14%, neutron detection efficiency ≥95%. These performance indicators exceed the commercial GS20 neutron detection glass and can be used as a high light yield glass scintillator for neutron detection.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] The high neutron detection efficiency and high light yield glass scintillator of the present invention comprises a main component and a reducing agent; the mass percentages of the raw materials of the main component are: SiO2 40-60%, Li2O 10-22%, Al2O3 4-10%, CeO24-12%, MgO 2-10%, XF n 0-25%, wherein X is one or more of alkaline metal elements, alkaline earth metal elements, boron group elements, and rare earth elements; the alkaline metal is Li and / or Na; the alkaline earth metal element is Mg and / or Zn; the boron group element is Al and / or Ga; the rare earth element is one or more of Y, La, and Gd; n is determined according to the corresponding metal valence state selected by X, and XF n Not equal to 0; the remainder is the reducing agent.

[0010] The reducing agent is one or more of Sb2O3, AlN, SiC and Si3N4, and the mass percentage of the reducing agent in the glass scintillator with high neutron detection efficiency and high light yield is 0.2-1%.

[0011] The present invention provides a method for preparing a glass scintillator with high neutron detection efficiency and high light yield, comprising the following steps:

[0012] (1) According to the main components and reducing agent types of the selected glass scintillator with high neutron detection efficiency and high light yield and the corresponding proportions, corresponding raw materials are selected and mixed evenly to obtain a glass batch material for standby use;

[0013] (2) placing the glass batch material in a corundum crucible or a quartz crucible and placing it in a high-temperature reducing atmosphere furnace, wherein the glass batch material is exposed to the reducing atmosphere for high-temperature melting;

[0014] (3) The high-temperature melted glass is poured onto an annealing mold for annealing and slowly cooled to room temperature to obtain the desired high neutron detection efficiency and high light yield glass scintillator.

[0015] In the step (1), the raw material of lithium oxide in the glass scintillator with high neutron detection efficiency and high light yield is selected from natural abundant lithium, natural lithium carbonate or enriched 6 One or more oxides of Li (mass percentage content ≥ 95%).

[0016] In the step (1), in the glass scintillator with high neutron detection efficiency and high light yield, the reducing agent is one or more of Si3N4, Sb2O3, AlN, and SiC.

[0017] In the step (2), the reducing atmosphere of the high-temperature reducing atmosphere furnace is a nitrogen-hydrogen mixed gas. Preferably, in terms of volume percentage, hydrogen:nitrogen = (5%-10%): (90%-95%), more preferably 5%:95%.

[0018] Preferably, in step (2), the high temperature melting temperature is 1100-1400°C, the melting time is 60-180 min, and the melting atmosphere is a reducing atmosphere.

[0019] The step (2) further includes a step of stirring the molten glass after high-temperature melting before pouring it into the annealing mold.

[0020] In the step (3), the annealing mold is preferably an annealing mold made of stainless steel.

[0021] Preferably, in step (3), the preheating temperature of the annealing mold is 400-600°C.

[0022] Preferably, in step (3), the annealing temperature is 400-600° C., and the annealing time is 3-6 hours.

[0023] Preferably, in the step (3), after the annealing, the step further includes: cooling the temperature, including cooling the temperature to 200° C. at a cooling rate of 5-10° C. / min, and then cooling the temperature to room temperature in the furnace.

[0024] The present invention also provides the application of the glass scintillator with high neutron detection efficiency and high light yield or the glass scintillator with high neutron detection efficiency and high light yield prepared by the above preparation method in the field of neutron detection.

[0025] The high neutron detection efficiency and high light yield glass scintillator has a light yield of 4200-8000ph / MeV under 662keV gamma light, an energy resolution of <16%, more preferably 12-13%; for thermal neutrons, the light yield is 6500-11000ph / n, the neutron gamma misjudgment rate is ≤14%, more preferably <10%, the thermal neutron resolution is 9.5-16%, and the neutron detection efficiency is ≥95%.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention discloses a glass scintillator with high neutron detection efficiency and high light yield, and a method for preparing and using the same. The mass percentage of lithium in the glass scintillator with high neutron detection efficiency and high light yield can reach up to 13.4%. While ensuring high lithium doping, the light yield of the glass is still as high as 8000ph / MeV, and the light yield reaches the level of BGO commercial crystals. It has excellent energy resolution (11%-13%), a high thermal neutron peak address, and a neutron gamma misjudgment rate of less than 10%, which is better than commercial GS20 lithium glass. By introducing fluorides with lower melting points, the preparation temperature of the glass can be effectively reduced. The preparation temperature of the present invention is 1100-1400°C, which is lower than the manufacturing temperature of commercial GS20 glass (1600°C), thereby reducing the difficulty of glass manufacturing. The introduction of fluorides can also reduce the phonon energy in the matrix, which can reduce Ce 3+ The probability of non-radiative transition of ions is increased, thereby improving the efficiency of fluorescence emission and increasing the light yield.

[0028] In the process of selecting fluorides, lithium fluoride is introduced to add more lithium elements to the glass scintillator. At the same time, the density of lithium fluoride is low, which further increases the thermal neutron response of the glass scintillator.

[0029] The present invention adopts atmosphere furnace melting and introduces a trace amount of reducing agent into the components to effectively provide a reducing atmosphere for the melting process of the glass, which can ensure that Ce in the glass scintillator with high Ce doping is 3+ The stability of the valence state enables molding after one melting.

[0030] The glass scintillator prepared by the present invention is easy to prepare in large size and can be prepared into a large optical device for use in the fields of neutron imaging and the like.

[0031] The glass scintillator with high neutron detection efficiency and high light yield uses Ce-doped lithium aluminum fluorine silicon system. The special network structure of fluorine silicon glass can effectively increase the Ce 3+ ions, and enables lower temperature melting of glass scintillator (compared to GS20). BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1The transmittance curve of the glass scintillator with high neutron detection efficiency and high light yield prepared in Example 3;

[0033] Figure 2 The emission spectrum of the glass scintillator with high neutron detection efficiency and high light yield prepared in Example 3 under X-ray excitation;

[0034] Figure 3 The gamma-ray pulse integrated spectra of the glass scintillator with high neutron detection efficiency and high light yield, BGO crystal and GS20 glass prepared in Example 4 at 662keV@Cs source;

[0035] Figure 4 The neutron response energy spectrum of the glass scintillator with high neutron detection efficiency and high light yield prepared in Example 4 under the Am-Be neutron source;

[0036] Figure 5 The neutron response energy spectrum of the glass scintillator with high neutron detection efficiency and high light yield prepared in Example 5 under the Am-Be neutron source;

[0037] Figure 6 This is a graph showing the neutron gamma ratio of the glass scintillator with high neutron detection efficiency and high light yield prepared in Example 6. DETAILED DESCRIPTION

[0038] The technical scheme of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. The described embodiments are only partial examples of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Example 1

[0040] The components and mass percentages of the glass scintillator with high neutron detection efficiency and high light yield are: 40SiO2-18Li2O-8Al2O3-8.5CeO2-10MgO-5YF3-5LiF-5LaF3-0.5Sb2O3

[0041] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0042] 2. Pour the mixed glass batch into a high-purity corundum crucible with a mass purity of more than 99%, and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes;

[0043] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a stainless steel annealing mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0044] Example 2

[0045] High neutron detection efficiency and high light yield glass scintillator, including components and their mass percentages: 40SiO2-18Li2O-8Al2O3-8.5CeO2-10MgO-5YF3-5LiF-5AlF3-0.5Sb2O3

[0046] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0047] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0048] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a stainless steel annealing mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0049] Example 3

[0050] The components and mass percentages of the glass scintillator with high neutron detection efficiency and high light yield are: 40SiO2-18Li2O-8Al2O3-8.5CeO2-5MgO-5LaF3-5YF3-5LiF-5AlF3-0.5Sb2O3

[0051] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0052] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0053] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a stainless steel annealing mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0054] The transmittance of the glass scintillator with high neutron detection efficiency and high light yield was tested, and the transmittance curve is shown in Figure 1 It can be seen that the transmittance of Example 3 at 400nm is about 90%. Its excellent transmittance can reduce the self-absorption of the sample and ensure the excellent scintillation performance of the sample. The emission spectrum of the prepared high neutron detection efficiency and high light yield glass scintillator under X-ray excitation is shown in Figure 2 It can be seen that the XEL luminescence peak of Example 3 is 390nm. Compared with the commercial scintillation crystal BGO, its peak intensity is about 6 times that of BGO.

[0055] Example 4

[0056] The components and mass percentages of glass scintillators with high neutron detection efficiency and high light yield are:

[0057] 40SiO2-13Li2O-8Al2O3-10.5CeO2-5MgO-8YF3-10LiF-5LaF3-0.5Sb2O3

[0058] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0059] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0060] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a stainless steel annealing mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0061] The high neutron detection efficiency and high light yield glass scintillator was tested under gamma rays, and its gamma ray impulse spectrum is shown in Figure 3 , and detected the gamma-ray pulse integrated spectra of BGO crystal and GS20 glass. Figure 3It can be seen that the channel number is obtained by performing Gaussian fitting on the full energy peak of 662keV, and by comparing the GS20 sample, the glass sample of Example 4 and the BGO crystal standard sample, it is calculated that the light yield of the BGO crystal standard sample is 8843ph / MeV, the light yield of the glass sample of Example 4 is 5436ph / MeV, and the light yield of the GS20 sample is 2171ph / MeV. According to the product information of the GS20 sample, the light yield of the GS20 sample is 4000ph / MeV. The reason for the low light yield of the GS20 sample test sample is that the sample thickness is only 1mm, but the Compton cutoff edge of the sample can be clearly observed.

[0062] Under the Am-Be neutron source, the neutron response energy spectrum of the glass scintillator with high neutron detection efficiency and high light yield prepared in this embodiment is shown in Figure 4 It can be seen that the thermal neutron peak of this embodiment is clear, and its thermal neutron resolution is calculated to be 11.98%.

[0063] Example 5

[0064] The components and mass percentages of the glass scintillator with high neutron detection efficiency and high light yield are: 44SiO2-5MgO-8Al2O3-18Li2O-10LiF-5AlF3-9.5CeO2-0.5Sb2O3

[0065] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0066] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0067] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a stainless steel annealing mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0068] Under the Am-Be neutron source, the neutron response energy spectrum of the glass scintillator with high neutron detection efficiency and high light yield prepared in this embodiment is shown in Figure 5 It can be seen that the thermal neutron peak of this embodiment is clear, and its thermal neutron resolution is calculated to be 10.90%.

[0069] Example 6

[0070] The components and their mass percentages of the glass scintillator with high neutron detection efficiency and high light yield are:

[0071] 45SiO2-5MgO-8Al2O3-18Li2O-10LiF-5AlF3-7.5CeO2-0.5Sb2O3

[0072] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0073] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1380°C and the melting time is 80 minutes.

[0074] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a stainless steel annealing mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0075] The neutron gamma ratio of the glass scintillator with high neutron detection efficiency and high light yield prepared in this embodiment is shown in Figure 6 By performing Gaussian fitting on the thermal neutron peak and using a quadratic polynomial to derive the gamma-ray background, the proportion of gamma rays within 3 times the standard deviation was obtained, and the gamma-ray percentage in this embodiment was calculated to be 9.5%.

[0076] Example 7

[0077] The components and mass percentages of the glass scintillator with high neutron detection efficiency and high light yield are: 46SiO2-5MgO-8Al2O3-18Li2O-10LiF-5AlF3-6.5CeO2-0.5Sb2O3

[0078] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0079] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0080] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0081] Example 8

[0082] The components and their mass percentages of the glass scintillator with high neutron detection efficiency and high light yield are:

[0083] 50SiO2-5MgO-5Al2O3-20Li2O-10LiF-5AlF3-4.5CeO2-0.5Sb2O3

[0084] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, weigh the raw materials and fully grind and mix them to obtain a glass batch;

[0085] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1400°C and the melting time is 80 minutes.

[0086] 3. Stir the glass melt in the crucible with a quartz rod and pour it into a mold preheated at 500℃ to cool and shape it. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain a glass scintillator with high neutron detection efficiency and high light yield.

[0087] Example 9

[0088] The raw material composition and preparation method of the glass scintillator with high neutron detection efficiency and high light yield described in this embodiment are the same as those in embodiment 1, the only difference is that the raw material of lithium oxide is selected from enriched 6 Li(95%)CO3 compound.

[0089] The components and their corresponding mass percentages of scintillating glass are: 40SiO2-5MgO-8Al2O3-13 6 Li2O-8YF3-10LiF-5LaF3-10.5CeO2-0.5Sb2O3

[0090] 1. Weigh 30g of the raw materials according to the above glass components and grind and mix them evenly;

[0091] 2. Pour the mixed glass raw materials into a high-purity corundum crucible, add a corundum cover on the crucible, and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0092] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain scintillation glass.

[0093] Comparative Example 1

[0094] The raw material composition and preparation method of the high neutron detection efficiency and high light yield glass scintillator described in this embodiment are the same as those in Embodiment 2, the only difference being that the crucible is a silicon nitride crucible.

[0095] The components and mass percentages of scintillating glass are: 40SiO2-10MgO-8Al2O3-18Li2O-5AlF3-5LiF-5YF3-8.5CeO2-0.5Sb2O3

[0096] 1. According to the above scintillation glass components, weigh 30g of raw materials and grind and mix them evenly;

[0097] 2. Pour the uniformly mixed glass batch into a high-purity silicon nitride crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0098] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain scintillation glass.

[0099] Comparative Example 2

[0100] The raw material composition and preparation method of the glass scintillator with high neutron detection efficiency and high light yield described in this comparative example are the same as those in Example 5, the only difference being that the reducing agent is C.

[0101] The components and their corresponding mass percentages of scintillating glass are: 44SiO2-5MgO-8Al2O3-18Li2O-10LiF-5AlF3-9.5CeO2-0.5C

[0102] 1. Weigh 30g of the raw materials according to the above glass components and grind and mix them evenly;

[0103] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0104] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain scintillation glass.

[0105] Comparative Example 3

[0106] The raw material composition and preparation method of the glass scintillator with high neutron detection efficiency and high light yield described in this comparative example are the same as those in Example 1, the only difference being that the crucible is covered.

[0107] The components and their corresponding mass percentages of scintillating glass are: 40SiO2-10MgO-8Al2O3-18Li2O-5YF3-5LiF-5LaF 3- 8.5CeO2-0.5Sb2O3

[0108] 1. Weigh 30g of the raw materials according to the above glass components and grind and mix them evenly;

[0109] 2. Pour the mixed glass batch into a high-purity corundum crucible and cover the crucible. Melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1350°C and the melting time is 80 minutes.

[0110] 3. Stir the glass melt in the crucible with a quartz rod for 0-5 seconds, then pour it into a mold preheated at 500℃ and cool it into shape. Then transfer it to a 500℃ annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, cool it to room temperature with the furnace to obtain scintillation glass. After the corundum crucible is covered, bubbles will appear inside the glass, resulting in a decrease in indicators such as light yield.

[0111] Comparative Example 4

[0112] The glass scintillator components and their mass percentages are:

[0113] 50SiO2-20Li2O-10Al2O3-10CeO2-10MgO

[0114] 1. According to the above-mentioned high neutron detection efficiency and high light yield glass scintillator components, 30 g of raw materials are weighed and fully ground and mixed to obtain a glass batch;

[0115] 2. Pour the mixed glass batch into a high-purity corundum crucible and melt it into a uniform glass melt in a reducing atmosphere with a nitrogen and hydrogen volume ratio of 95:5. The melting temperature is 1400°C and the melting time is 80 minutes.

[0116] 3. The glass melt in the crucible is stirred with a quartz rod for 0-5 seconds, then poured into a stainless steel annealing mold preheated at 500°C and cooled to form, and then transferred to a 500°C annealing furnace for constant temperature annealing to eliminate internal stress. After keeping warm for 3 hours, it is cooled to room temperature with the furnace to obtain a glass scintillator. In this comparative example, the fluoride in the embodiment is deleted and the scintillator glass is tested. Its scintillation performance is not as good as the high neutron detection efficiency and high light yield glass scintillator of the present invention.

[0117] Table 1 Performance test results of high light yield glass scintillator for neutron detection

[0118]

[0119]

[0120] It can be seen from the data in the above table that the high neutron detection efficiency and high light yield glass scintillator provided by the present invention has a high light yield of 4200-8000ph / MeV, and an energy resolution of less than 16%, among which the energy resolution of Examples 4 and 5 is as low as 13%, the thermal neutron resolution is excellent, the thermal neutron light yield is ≥6500-11000ph / n, and the neutron gamma discrimination effect is good.

[0121] In Comparative Example 1, a silicon nitride crucible was selected, and the silicon nitride in the silicon nitride crucible was used as a reducing agent to provide an additional reducing atmosphere for the glass during the melting process. However, due to the poor density of the silicon nitride crucible and the large amount of internal impurities, the powder raw material will be converted into glass liquid at high temperature and react with the silicon nitride crucible. The impurities in the crucible enter the glass liquid, and the sample does not become glass. In Comparative Example 2, the reducing agent is changed to C, and the sample is colored, resulting in obvious self-absorption of the sample, resulting in a decrease in the scintillation performance of the sample. In Comparative Example 4, after removing the fluoride from the components, it can be found that the scintillation performance of the glass is significantly reduced. This embodiment proves that Ce 3+ Doped fluorosilicates compared to Ce 3+ Doped silicate glass has advantages in indicators such as light yield, energy resolution, neutron yield, thermal neutron resolution and neutron gamma discrimination capability.

[0122] Obviously, the above embodiments are merely examples for the purpose of clarifying the description, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A glass scintillator with high neutron detection efficiency and high light yield, characterized in that: The high neutron detection efficiency and high light yield glass scintillator comprises a main component and a reducing agent; the mass percentages of the raw materials of the main component are: SiO2 40-60%, Li2O 10-22%, Al2O3 4-10%, CeO2 4-12%, MgO 2-10%, XF n 0-25%, wherein X is one or more of alkaline metal elements, alkaline earth metal elements, boron elements, and rare earth elements; n is determined according to the metal valence state corresponding to X, and XF n Not equal to 0; the remainder is the reducing agent.

2. The glass scintillator with high neutron detection efficiency and high light yield according to claim 1, characterized in that: The alkaline metal is Li and / or Na; the alkaline earth metal element is Mg and / or Zn; the boron group element is Al and / or Ga; and the rare earth element is one or more of Y, La, and Gd.

3. The glass scintillator with high neutron detection efficiency and high light yield according to claim 1, characterized in that: The reducing agent is one or more of Sb2O3, AlN, SiC and Si3N4, and the mass percentage of the reducing agent in the glass scintillator with high neutron detection efficiency and high light yield is 0.2-1%.

4. The glass scintillator with high neutron detection efficiency and high light yield according to claim 1, characterized in that: The high neutron detection efficiency and high light yield glass scintillator has a light yield of 4200-8000ph / MeV and an energy resolution of <16% under 662keV gamma light; a light yield of 6500-11000ph / n for thermal neutrons, a neutron gamma misjudgment rate of ≤14%, a thermal neutron resolution of 9.5-16%, and a neutron detection efficiency of ≥95%.

5. The method for preparing a glass scintillator with high neutron detection efficiency and high light yield according to any one of claims 1 to 4, characterized in that: The steps include: (1) According to the main components and reducing agent types of the selected glass scintillator with high neutron detection efficiency and high light yield and the corresponding proportions, corresponding raw materials are selected and mixed evenly to obtain a glass batch material for standby use; (2) placing the glass batch material in a high-purity corundum crucible or a quartz crucible, and placing the crucible in a high-temperature reducing atmosphere furnace, and exposing the glass batch material to the reducing atmosphere for high-temperature melting; (3) The high-temperature melted glass is poured onto an annealing mold for annealing and slowly cooled to room temperature to obtain the desired high neutron detection efficiency and high light yield glass scintillator.

6. The method for preparing a glass scintillator with high neutron detection efficiency and high light yield according to claim 5, characterized in that: The raw materials of lithium oxide are natural abundant lithium, natural lithium carbonate or enriched lithium 6 with an abundance of ≥95%. 6 One or more of Li oxides.

7. The method for preparing a glass scintillator with high neutron detection efficiency and high light yield according to claim 5, characterized in that: In the step (2), the reducing atmosphere of the high-temperature reducing atmosphere furnace is a nitrogen-hydrogen mixed gas, in which, by volume percentage, hydrogen:nitrogen = (5%-10%): (90%-95%).

8. The method for preparing a glass scintillator with high neutron detection efficiency and high light yield according to claim 5, characterized in that: In the step (2), the high temperature melting temperature is 1100-1400°C, and the melting time is 60-180 minutes.

9. The method for preparing a glass scintillator with high neutron detection efficiency and high light yield according to claim 5, characterized in that: In the step (3), the annealing temperature is 400-600° C. and the annealing time is 3-6 hours; and / or, After the annealing, the process further includes: cooling the temperature to 200° C. at a cooling rate of 5-10° C. / min, and then cooling the temperature to room temperature in the furnace.

10. Use of the high neutron detection efficiency and high light yield glass scintillator according to any one of claims 1 to 4 or the high neutron detection efficiency and high light yield glass scintillator prepared by the preparation method according to any one of claims 5 to 9 for neutron detection.

Images