Method for testing the rapid recovery of color change of blue sintered zirconia irradiated by x-rays

Abstract

The application discloses an X-ray irradiation blue synthesis zirconia color change rapid recovery test method, which comprises the following steps: step one, preparing powder according to the mole percentage; step two, adopting a cold crucible floating zone method to synthesize blue zirconia; step three, performing X-ray irradiation on the blue synthesized zirconia crystal to make the blue synthesized zirconia crystal change color; step four, heat treatment; step five, ultraviolet light irradiation; step six, photographing and comparing the synthesized zirconia after irradiation, heat treatment and ultraviolet light irradiation, and determining the chroma of the synthesized zirconia by using a fiber spectrometer to seek the optimal heat treatment and light irradiation parameters for recovering the color to the original chroma before irradiation. Through the rapid recovery test of the irradiation color change of the synthesized zirconia, the new material which can be recycled multiple times and takes into account the economic and environmental benefits is sought, a new selection is provided for the radiation leakage indication lamp material, and the X-ray radiation leakage indication lamp is easier to popularize and apply to the market.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material preparation and color change recovery, and particularly relates to a test method for rapid recovery of color change of X-ray irradiated blue synthetic cubic zirconia. BACKGROUND

[0002] X-rays are widely used in military, medical, scientific, industrial and agricultural fields. Among them, the medical field is the most common, especially medical diagnostic X-rays, which are important artificial ionizing radiation sources for human application; in the industrial field, X-rays are also commonly used in industrial non-destructive testing, such as semiconductor and foreign object detection. With the increasing demand for X-ray equipment in various fields, its application range is also expanding, but the potential hazards of X-ray radiation are also inevitable. In-depth analysis of radiation protection research is beneficial to timely detection of radiation leakage problems, elimination of potential dangers, and protection of personnel safety, which is of great significance for effectively promoting the application of X-rays.

[0003] At present, as the material of the radiation leakage indication lamp, such as the yellow sapphire in Sri Lanka, is expensive, and the color is not obvious during the recovery test after irradiation color change, and it cannot be repeatedly tested. As a synthetic cubic zirconia is a high-strength and high-fire crystal, also known as "CZ diamond", due to its relatively low price, it is used as the preferred material for the radiation leakage indication lamp. The chemical formula of the synthetic cubic zirconia is ZrO2, which belongs to the isometric system, and the Mohs hardness is 7.5-8.5. It is generally artificially synthesized by cold crucible floating zone method. The growth method of the cold crucible method adopts spontaneous crystallization. It is hoped that through the color change recovery test of the synthetic cubic zirconia, the best application mode of the synthetic cubic zirconia as the material of the radiation leakage indication lamp can be explored. SUMMARY

[0004] The present application aims to seek new materials that can be recycled multiple times, taking into account economic and environmental benefits, through recovery tests of synthetic cubic zirconia after irradiation color change, to provide new options for radiation leakage indication lamp materials, and to make X-ray radiation leakage indication lamps more easily applied to the market.

[0005] To this end, the technical scheme adopted by the present application is as follows: a test method for rapid recovery of color change of X-ray irradiated blue synthetic cubic zirconia, comprising the following steps:

[0006] Step 1: Prepare the powder according to the mole percentage, ZrO2: Y2O3: HfO2: Co2O3: CeO2: Pr6O 11 : Er2O3 = 75-80: 23-28: 1-6: 0.5-0.8: 0.02-0.06: 0.02-0.04: 0.01-0.06, wherein Co2O3 is used as a colorant, and CeO2, Pr6O 11Er2O3 is used for providing rare earth elements; after mixing all the powders, the powders are stirred uniformly;

[0007] Step two, adopting a cold crucible floating zone method to synthesize cubic zirconia crystals in blue color;

[0008] Step three, X-ray irradiation is performed on the synthesized cubic zirconia crystals in blue color under different irradiation time and dose parameters, so that the synthesized cubic zirconia crystals in blue color are discolored, the irradiation time ranges from 10 min to 40 min, and the irradiation dose is 3.06*10 6 ~1.12*10 7 J / cm 2 ;

[0009] Step four, heat treatment: the synthesized cubic zirconia crystals in blue color which are discolored after X-ray irradiation are placed in a high-temperature atmosphere tube furnace, and are heated to 200-400 DEG C under an oxygen atmosphere, and are kept for 1-2 h, and are taken out and cooled at room temperature;

[0010] Step five, ultraviolet light irradiation: the synthesized cubic zirconia crystals are irradiated by ultraviolet light for different time, so that the color of the synthesized cubic zirconia crystals is recovered, the wavelength of the ultraviolet light ranges from 320 nm to 400 nm, and the irradiation time ranges from 1 h to 2 h;

[0011] Step six, the synthesized cubic zirconia crystals after irradiation, heat treatment and ultraviolet light irradiation are photographed and compared, and the chroma of the synthesized cubic zirconia crystals is measured by using a fiber spectrometer, so that the best heat treatment and light irradiation parameters for recovering the color to the original chroma before irradiation are sought.

[0012] As a preferred embodiment of the present application, in step two, 4-6 g of metal zirconium sheets are put in the center of the powders for "ignition", and the powders are heated to melting by using a high-frequency coil, so that a molten pool is generated and expanded, then cold water is passed through the purple steel tube to cool the outer layer, so that the outer layer is not melted, and a "cold crucible floating zone" is formed; after the powders are completely melted, the molten pool is kept stable for 50-60 min, then the crystalline material which is melted in the interior is crystallized and grown by passing through the cooling under the crucible, and finally transparent blue synthesized cubic zirconia crystals are obtained.

[0013] Further preferably, in step two, the powders are heated to above 1400 DEG C by using a high-frequency coil.

[0014] Further preferably, in step three, the X-ray irradiation has a power ranging from 500 w to 4000 w.

[0015] Further preferably, in step six, the photographing parameters are as follows: the sensitivity is 80, the shutter speed is 1 / 60 s, the aperture is 1.8, and the focal length is 54 mm.

[0016] The present application has the following beneficial effects:

[0017] (1) The blue synthesized zirconia prepared by adding rare earth elements Ce, Pr and Er is sensitive to radiation. X-ray irradiation can easily cause the excited state of Ce, Pr and Er elements to change, oxygen vacancies are generated, transition occurs between them, and finally color change occurs. The material is used as a radiation leakage indicator lamp, which has obvious visual advantages.

[0018] (2) After the color change of the blue synthesized zirconia, the process of heat treatment and ultraviolet light irradiation is used to change the excited state back to the ground state, and the color recovery process is completed. The material has the characteristics of multiple recycling, and takes into account economic and environmental benefits, and implements the concept of low cost and green sustainable development, providing a new choice for color-changing recoverable materials.

[0019] (3) The composite process of heat treatment and ultraviolet light irradiation only needs to be heated at 200-400℃ in oxygen atmosphere for 1-2h and irradiated under ultraviolet lamp for 1-2h, which can quickly recover the color change in total 2-4h, which is very efficient and fast. At the same time, the combination of the two recovery processes can reduce the addition amount of rare earth elements, which is more conducive to reducing the cost of raw materials.

[0020] (4) The combination of rare earth element doping, irradiation color changing technology, heat treatment technology and ultraviolet light irradiation test can effectively realize the rapid color change of blue synthesized zirconia, so as to realize the purpose of radiation color change. After heat treatment and ultraviolet light irradiation test, the synthesized zirconia can quickly recover the original color for continuous use, which is simple and fast.

[0021] (5) Through comparative test, it is found that if 0.5-0.8mol% Co2O3 is added as colorant, and the content of CeO2, Pr6O 11 , Er2O3 is lower than the set range, the finally generated crystal is light blue, CeO2 is higher than 0.15mol%, the generated crystal is orange, Pr6O 11 is higher than 0.08mol%, the generated crystal is yellow, and Er2O3 is higher than 0.12mol%, the generated crystal is pink. Selecting appropriate ratio to prepare blue synthesized zirconia, the color contrast after X-ray irradiation is more distinct, which is more conducive to determining the color recovery after color change. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The color contrast of blue synthesized zirconia before irradiation, X-ray irradiation for 10, 20 and 40min.

[0023] Figure 2 The color recovery state of zirconia after irradiation color change after heat treatment and ultraviolet light irradiation, and the color remains consistent after repeated multiple times. DETAILED DESCRIPTION

[0024] The application will be further described below by way of examples and with reference to the accompanying drawings:

[0025] A test method for X-ray irradiation blue synthesized zirconia color change rapid recovery, comprising the following steps:

[0026] Step one, according to the mole percentage to prepare the powder, ZrO2: Y2O3: HfO2: Co2O3: CeO2: Pr6O 11 : Er2O3 = 75 ~ 80: 23 ~ 28: 1 ~ 6: 0.5 ~ 0.8: 0.02 ~ 0.06: 0.02 ~ 0.04: 0.01 ~ 0.06, wherein, Co2O3 as colorant, CeO2, Pr6O 11 , Er2O3 for providing rare earth elements. After mixing all the powder, stir evenly. Cubic zirconia (CZ) is a single crystal ceramic, Y2O3, HfO2 as a stabilizing additive, can make the cubic structure of ZrO2 to maintain in the low temperature region, a small amount of HfO2 can enhance the thermal shock resistance.

[0027] Step two, using cold crucible floating zone method of blue synthesized cubic zirconia.

[0028] Cold crucible floating zone method belongs to the method commonly used in crystal growth. First, in the center of the powder into 4 ~ 6g metal zirconium sheet for "ignition", using high frequency coil heating to raw material melting, to produce and expand the pool, after the passage of cold water cooling in purple steel tube, the outer layer of not melting, forming "cold crucible floating zone"; after the powder completely melted, stable melt 50 ~ 60min, the internal has been melted crystal material, rely on the crucible to drop the cooling to make it crystallization growth, finally get the transparent blue synthesized cubic zirconia crystal. Preferably, using high frequency coil heating to 1400 DEG C or more.

[0029] Step three, the blue synthesized cubic zirconia crystal is irradiated by X-ray with different irradiation time and dose parameters, so that it produces color change, the irradiation time range is 10 ~ 40min, the irradiation dose is 3.06x10 6 ~ 1.12x10 7 J / cm 2 . Preferably, the X-ray irradiation with power range of 500 ~ 4000w is selected.

[0030] Step four, heat treatment: the synthesized cubic zirconia crystal with different color change degree after X-ray irradiation is placed in a high temperature atmosphere tube furnace, heated to 200 ~ 400 DEG C under oxygen atmosphere, and then kept for 1 ~ 2h, and then cooled to room temperature.

[0031] Step five, UV light irradiation: the color of the synthesized cubic zirconia crystals is recovered by UV light irradiation with different time length. The wavelength range of the UV irradiation is 320-400 nm, and the irradiation time length is 1-2 h.

[0032] Step six, the synthesized cubic zirconia after various irradiation, heat treatment and UV irradiation is photographed for comparison. Preferably, the photographing parameters are: sensitivity 80, shutter speed 1 / 60 s, aperture 1.8, and focal length 54 mm. The chroma of the synthesized cubic zirconia is determined by using a fiber spectrometer to seek the optimal heat treatment and irradiation parameters for recovering the color to the original chroma before irradiation.

[0033] Examples:

[0034] A plurality of blocky blue synthesized cubic zirconia doped with Co element and rare earth elements Ce, Pr and Er with a diameter of 1 cm is irradiated with X-rays of different doses, and the color changes from blue to brownish yellow, as shown in Table 1.

[0035] Table 1 X-ray irradiation data of Examples 1-3

[0036] Group X-ray irradiation time (min) X-ray irradiation dose (J / cm 2 ) Example 1 10 3.06 x 10 6 ]] Example 2 20 6.12 x 10 6 ]]> Example 3 40 1.12 x 10 7 ]]

[0037] The samples are then subjected to heat treatment and UV irradiation, respectively. The heat treatment is carried out by using a high-temperature atmosphere tube furnace to heat to 200-300℃ at a rate of 5℃ / min and then holding for 1 h. The UV irradiation is carried out by using a UV lamp with a wavelength of 320-400 nm for 1 h.

[0038] The synthesized cubic zirconia after various irradiation, heat treatment and UV irradiation is photographed for comparison, and the chroma of the synthesized cubic zirconia is determined by using a fiber spectrometer to seek the optimal heat treatment and irradiation parameters for recovering the color to the original chroma before irradiation. Table 2 is the chroma data of Examples 1-3.

[0039] Table 2 Chroma data of Examples 1-3

[0040] Group L a* b* Before X-ray irradiation 60.88 -14.05 40.27 Example 1 60.19 -16.15 34.08 Example 2 60.16 -12.23 47.35 Example 3 61.17 -11.32 48.69

[0041] Among them:

[0042] 1) Examples 1, 2 and 3 are respectively the synthesized cubic zirconia obtained by irradiation for 10, 20 and 40 min, which is compared with the photograph of the synthesized cubic zirconia before irradiation. Figure 1 It can be seen that the color of the blue synthesized cubic zirconia changes from blue to brownish yellow after irradiation for 10 min, and the brownish yellow tone increases obviously after further irradiation. It can be seen that the color of the synthesized cubic zirconia after irradiation changes obviously.

[0043] 2) From Table 2, it can be seen that the chroma of the synthesized cubic zirconia after irradiation for 10 min is 10.5, which is much lower than the chroma of the synthesized cubic zirconia before irradiation. Figure 2It can be seen that the brownish yellow zirconia after irradiation, after heat treatment at 200-300℃ for 1h and UV irradiation for 1h, the final color is restored from brownish yellow to the original blue. After more than 5 repeated tests, the color recovery is still consistent.

[0044] 3) The colorimetric values in Table 2 are obtained by using a USB2+H07263 fiber-optic spectrometer, selecting D65 light source to collect the color of Examples 1-3, and using CIE-Lab color coordinate system to measure the color of each prepared cubic zirconia.

[0045] The present application uses rare earth elements incorporated during preparation, changes the valence state inside the blue cubic zirconia prepared by X-ray irradiation to make it produce color change, and then restores its color through heat treatment and light test, to obtain a color-changing recoverable material. The present application can not only change the color of blue cubic zirconia prepared by rare earth elements through irradiation, but also restore it through heat treatment and light test, and finally recycle and use multiple times, meeting the requirements of color-changing recoverable materials.

[0046] Comparative Test 1: This test has a final transparent blue cubic zirconia crystal. If 0.5-0.8mol% Co2O3 is added as a colorant, CeO2, Pr6O 11 , Er2O3 is lower than the set range, the final generated crystal is light blue, CeO2 is higher than 0.15mol%, the generated crystal is orange, Pr6O 11 is higher than 0.08mol%, the generated crystal is yellow, and Er2O3 is higher than 0.12mol%, the generated crystal is pink.

[0047] Comparative Test 2: Comparative test with blue cubic zirconia only added with Co element and not doped with rare earth elements. The results show that: the blue cubic zirconia doped with rare earth elements changes from blue to blue-green after X-ray irradiation, and the brownish yellow tone increases significantly after further irradiation, and after 40min, the brownish yellow tone no longer increases with the increase of irradiation dose; the blue cubic zirconia not doped with rare earth elements cannot complete the change of valence state of Ce, Pr and Er elements excited, produce oxygen vacancies, and transition between them, finally produce color change.

[0048] Comparative Experiment 3: The blue doped rare earth element zirconia was irradiated by X-ray to become brown yellow, then the zirconia was treated by heat at 200-400℃ for 1-2h, and irradiated by ultraviolet light at 320-400nm for 1-2h, the final color of the zirconia returned to the original blue color. But if the heat treatment temperature is lower than 200℃, or the ultraviolet light irradiation is less than 1h, the color will change from brown yellow to blue green, and cannot completely restore the blue color; conversely, if the heat treatment temperature is higher than 400℃, or the ultraviolet light irradiation is more than 2h, the color will remain blue.

Claims

1. A rapid recovery test method for discoloration of blue synthetic cubic zirconia irradiated with X-rays, characterized in that, Includes the following steps: Step 1: Prepare the powder according to the molar percentage: ZrO2:Y2O3:HfO2:Co2O3:CeO2:Pr6O 11 Er₂O₃ = 75~80: 23~28: 1~6: 0.5~0.8: 0.02~0.06: 0.02~0.04: 0.01~0.06, where Co₂O₃ is used as a colorant, and CeO₂ and Pr₆O₃ are used as colorants. 11 Er₂O₃ is used to provide rare earth elements; all powders are mixed and stirred evenly, and the sum of the molar percentages of all the above components is 100%. Step 2: Blue cubic zirconia is synthesized using the cold crucible melting shell method; Step 3: The blue synthetic cubic zirconia crystal was irradiated with X-rays under different irradiation durations and dose parameters to induce a color change. The irradiation duration ranged from 10 to 40 minutes, and the irradiation dose was 3.06 × 10⁻⁶. 6 ~1.12×10 7 J / cm 2 ; Step 4, heat treatment: Place the synthetic cubic zirconia crystals with different degrees of discoloration after X-ray irradiation in a high-temperature atmosphere tube furnace, heat them to 200~400℃ in an oxygen atmosphere and hold them at that temperature for 1~2 hours, then remove them and cool them to room temperature. Step 5, UV light irradiation: The synthetic cubic zirconia crystal is irradiated with a UV lamp for different durations to restore its color. The wavelength range of the UV light irradiation is 320~400nm, and the irradiation duration ranges from 1 to 2 hours. Step six involves photographing and comparing the synthetic cubic zirconia after various irradiations, heat treatments, and ultraviolet light irradiations, and using a fiber optic spectrometer to measure the color of these synthetic cubic zirconias to find the optimal heat treatment and irradiation parameters for restoring the color to its original color before irradiation.

2. The rapid recovery test method for discoloration of blue synthetic cubic zirconia under X-ray irradiation according to claim 1, characterized in that: In step two, 4-6g of metallic zirconium sheet is placed in the center of the powder for "ignition". The raw material is heated to melt using a high-frequency coil to generate and expand the molten pool. Then, cold water is passed through a steel tube to cool it, so that the outer layer does not melt, forming a "cold crucible shell". After the powder is completely melted, the melt is stabilized for 50-60 minutes. The molten crystal material inside is cooled by the descent of the crucible to allow it to crystallize and grow, finally obtaining a transparent blue synthetic cubic zirconium oxide crystal.

3. The rapid recovery test method for discoloration of blue synthetic cubic zirconia under X-ray irradiation according to claim 2, characterized in that: In step two, the high-frequency coil is heated to above 1400℃.

4. The rapid recovery test method for discoloration of blue synthetic cubic zirconia under X-ray irradiation according to claim 1, characterized in that: In step three, X-ray irradiation with a power range of 500~4000w is selected.

5. The rapid recovery test method for discoloration of blue synthetic cubic zirconia under X-ray irradiation according to claim 1, characterized in that: In step six, the shooting parameters are ISO 80, shutter speed 1 / 60 second, aperture 1.8, and focal length 54mm.

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