CN115266795A - Method for representing diffusion behavior of fission gas product of strong radioactive fuel element - Google Patents
Method for representing diffusion behavior of fission gas product of strong radioactive fuel element Download PDFInfo
- Publication number
- CN115266795A CN115266795A CN202210908933.5A CN202210908933A CN115266795A CN 115266795 A CN115266795 A CN 115266795A CN 202210908933 A CN202210908933 A CN 202210908933A CN 115266795 A CN115266795 A CN 115266795A
- Authority
- CN
- China
- Prior art keywords
- sample
- fission gas
- fuel element
- loading
- clamping seat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000446 fuel Substances 0.000 title claims abstract description 97
- 230000004992 fission Effects 0.000 title claims abstract description 70
- 238000000034 method Methods 0.000 title claims abstract description 64
- 238000009792 diffusion process Methods 0.000 title claims abstract description 51
- 230000002285 radioactive effect Effects 0.000 title claims abstract description 41
- 239000000523 sample Substances 0.000 claims abstract description 210
- 230000008569 process Effects 0.000 claims abstract description 39
- 239000000853 adhesive Substances 0.000 claims abstract description 25
- 230000001070 adhesive effect Effects 0.000 claims abstract description 25
- 238000012360 testing method Methods 0.000 claims abstract description 15
- 238000013508 migration Methods 0.000 claims abstract description 11
- 230000005012 migration Effects 0.000 claims abstract description 11
- 238000009826 distribution Methods 0.000 claims description 56
- 229910045601 alloy Inorganic materials 0.000 claims description 47
- 239000000956 alloy Substances 0.000 claims description 47
- 238000012512 characterization method Methods 0.000 claims description 30
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 15
- 239000010949 copper Substances 0.000 claims description 15
- 229910052802 copper Inorganic materials 0.000 claims description 15
- 230000008859 change Effects 0.000 claims description 13
- 239000000470 constituent Substances 0.000 claims description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 7
- 229910052799 carbon Inorganic materials 0.000 claims description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 229910052782 aluminium Inorganic materials 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 4
- 125000006850 spacer group Chemical group 0.000 claims 2
- 238000002360 preparation method Methods 0.000 abstract description 7
- 238000003825 pressing Methods 0.000 abstract description 2
- 230000006399 behavior Effects 0.000 description 21
- 239000003292 glue Substances 0.000 description 8
- 238000011160 research Methods 0.000 description 7
- 238000004458 analytical method Methods 0.000 description 5
- 229910008894 U—Mo Inorganic materials 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000012634 fragment Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000003758 nuclear fuel Substances 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 229910016338 Bi—Sn Inorganic materials 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000012141 concentrate Substances 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 229910003460 diamond Inorganic materials 0.000 description 2
- 239000010432 diamond Substances 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000227 grinding Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 229910000905 alloy phase Inorganic materials 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000005501 phase interface Effects 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 235000013547 stew Nutrition 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000011410 subtraction method Methods 0.000 description 1
- 238000012876 topography Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
- G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
- G01N23/225—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion
- G01N23/2251—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion using incident electron beams, e.g. scanning electron microscopy [SEM]
- G01N23/2252—Measuring emitted X-rays, e.g. electron probe microanalysis [EPMA]
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
- G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
- G01N23/2204—Specimen supports therefor; Sample conveying means therefore
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Monitoring And Testing Of Nuclear Reactors (AREA)
Abstract
The invention discloses a method for representing the diffusion behavior of fission gas products of a strong radioactive fuel element, which comprises the steps of loading a radioactive fuel sample by an electronic probe, and testing after loading the sample to obtain the migration diffusion behavior of the fission gas elements of the fuel element; the sample loading process comprises sample stage pretreatment: fixing the sample clamping seat on a sample table before sample loading by using the sample clamping seat as a sample fixing structure, and adjusting the height of the sample clamping seat to be matched with the size of the pole shoe of the electronic probe; sample loading: and fixing the sample in the notch of the sample clamping seat in the shielding glove box, pushing the sample into an electron microscope cabin for vacuumizing, and standing to finish sample loading. According to the invention, the refined operation of the sample loading process is concentrated in the preparation link, the subsequent sample loading can be completed by shielding the glove box and only pressing the conductive adhesive, so that the radioactive sample is prevented from being contacted in a short distance for a long time, and the radioactive dose borne by personnel is greatly reduced.
Description
Technical Field
The invention relates to the technical field of nuclear fuel circulation and irradiation effects, in particular to a method for representing the diffusion behavior of fission gas products of a strong radioactive fuel element based on an electronic probe.
Background
The plate-shaped dispersion type fuel is a common fuel element configuration such as an experimental stack and the like, and the structure of the plate-shaped dispersion type fuel is that fuel particles are dispersed in a matrix alloy. The plate element has many advantages, such as U-Mo/Al fuel, large heat exchange area, low service center temperature, strong capacity of accommodating fission products, high use fuel consumption, etc.
However, the plate member still has a problem that irradiation accelerates diffusion to degrade the performance of the fuel element. The fuel element core is exposed to extremely high radiation damage doses, mainly from high energy fission fragments, about 1dpa per day, which are much higher than the radiation damage doses to which the cladding material of the rod-type fuel element is exposed. Under the irradiation damage mainly based on high-energy fission fragments, the diffusion speed of elements such as various fission gas products such as Kr, xe and the like in the fuel phase is greatly accelerated. Research shows that under the irradiation of high energy fission fragments, the diffusion and migration rate of the U-Mo fuel element at 150 ℃ is more than 3 orders of magnitude faster than that of the U-Mo fuel element at the same temperature without irradiation.
Studying diffusion migration of elements in a plate member is of great importance to reveal degradation and failure of the plate member. Migration and diffusion of fission gas products will cause degradation of the mechanical and thermal properties of the fuel element. Such as Xe diffusion, leads to a wide interface region and enhanced scattering of the thermally conductive phonons by the crystal lattice, resulting in a decrease in interface thermal conductivity and mechanical properties. The decrease in thermal conductivity will have a self-accelerating effect, i.e. diffusion of the element will cause a decrease in thermal conductivity, which in turn will cause an increase in the temperature gradient in the fuel element, which in turn will promote diffusion of the element. This interaction promotion is extremely detrimental and may lead to initial failure of the fuel element.
Fission gas diffusion studies of irradiated fuel elements such as U-Mo also present certain difficulties. This is because: after the fuel element is irradiated, the fuel element has higher radioactive dose and easily releases volatile fission nuclide, so that the health and safety of characterization experimenters are easily damaged, precise characterization equipment is damaged, and the working environment is polluted.
Taking the existing characterization process of the Shimadzu electronic probe as an example, in the sample loading process of the sample, a clamp is needed to finely adjust a fixing screw to clamp the sample, and the observation surface of the sample is fastened and fixed at a specific height (keeping a working distance of 5 mm) and keeps good conductivity, so that micron-sized shaking and charge accumulation of the sample are avoided in the analysis process, and the sample is required to be closely contacted by an experimenter and finely operated for a long time. Using such a method would produce too high a dose to the experimenter without taking good measures to carry out the post-irradiation nuclear fuel characterization. If the above sample loading process is completed by using a glove box of a thick-walled lead glove having superior shielding performance, it is difficult to perform refinement.
Therefore, when the diffusion behavior of fission gas products is researched by adopting an electronic probe technology at present, the sample loading process still restricts the research on the diffusion behavior of fission gas elements and needs to be further improved.
Disclosure of Invention
The invention aims to solve the technical problem that when the diffusion behavior of fission gas products is researched by adopting an electronic probe technology at present, the sample loading process still restricts the research on the diffusion behavior of fission gas elements. The method aims to provide a method for representing the diffusion behavior of fission gas products of a strong radioactive fuel element based on an electronic probe so as to solve the problems.
The invention is realized by the following technical scheme:
a strong radioactive fuel element fission gas product diffusion behavior characterization method comprises the steps of loading a radioactive fuel sample by an electronic probe, and testing after loading the sample to obtain the migration diffusion behavior of the fission gas element of the fuel element;
the sample loading process comprises the following steps:
(1) Sample stage pretreatment: fixing the sample clamping seat on a sample table before sample loading by using the sample clamping seat as a sample fixing structure, and adjusting the height of the sample clamping seat to be matched with the size of the pole shoe of the electronic probe;
(2) Sample loading: and fixing the sample in the notch of the sample clamping seat in a shielding glove box, pushing the sample into an electron microscope cabin, vacuumizing, and standing to finish sample loading.
In an optional embodiment, the sample holder is fixed on the sample stage by using a conductive adhesive, and a gasket is used between the conductive adhesive and the sample holder to adjust the height of the sample holder.
In an optional embodiment, the gaskets are bonded by using conductive adhesive, the thickness of each gasket is 0.5mm, the diameter of each gasket is matched with that of the sample, and the gaskets are made of aluminum.
In an optional embodiment, the sample stage pre-treatment process further comprises: before sample loading, an original sample fixing device of the electronic probe equipment is disassembled to fix a sample clamping seat; adhering conductive carbon adhesive in the notch of the sample clamping seat to fix the sample;
in the sample stage pretreatment process, one ends of the copper conductive adhesives are pre-bonded on the outer side surface of the sample clamping seat, and the other ends of the copper conductive adhesives are connected with the sample when the sample is loaded in the glove box, so that the conductivity of the sample is improved.
In an alternative embodiment, during the characterization test on the test specimen, the interfacial bonding area of the fuel particles and the core alloy is analyzed to reference the fissile element distribution against the elemental distribution of the fuel element itself.
In an optional embodiment, during the characterization test of the test sample, the distribution of the fission element and the core alloy component element is measured at the interface combination of the fuel phase of the fuel element and the core alloy, and the migration and diffusion behaviors of the fission gas element are characterized by the relative position change of the distribution of the fission element and the core alloy component element.
In an alternative embodiment, the interface bonding region is subjected to surface scanning and line scanning analysis under a certain magnification to obtain an element distribution map of the constituent elements of the fissile element and the core alloy, and the obtained element distribution map of the constituent elements of the fissile element and the fuel element is subjected to combined mapping to obtain a relative positional change of the element distribution.
In an alternative embodiment, by adjusting the contrast of the secondary electron topography image, an interface bonding characteristic area of the fuel phase and the core alloy of the fuel element is searched;
after surface scanning and line scanning are carried out, the contrast of the fission gas element distribution image is adjusted by taking the core alloy far away from the fuel phase in the scanning area as a reference point 0, and the surface distribution and line distribution images of the fission gas elements are obtained to be combined and drawn with the obtained element distribution map of the fuel element composition elements.
In an alternative embodiment, the distance between the core alloy as the reference 0 point and the interface joint is 30-40 μm.
In an alternative embodiment, the magnification is 2000 times.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) The characterization method provided by the embodiment of the invention adopts a mode of preparing the sample clamping seat with the notch in advance in the sample loading process, mainly concentrates the preparation link of the operation in the sample loading process, and then completes the sample loading by only pressing the conductive adhesive through shielding the glove box in the sample loading process, thereby avoiding contacting radioactive samples in a short distance for a long time and greatly reducing the radioactive dose borne by personnel.
(2) The characterization method provided by the embodiment of the invention measures the fission elements and the core alloy at the interface of the fuel phase and the core alloy, combines the fission elements and the core alloy, and reflects the diffusion behavior of the fission gas elements by the relative position change of the fission elements and the core alloy; meanwhile, the fissile element content contrast of the core alloy micro-area far away from the fuel phase is taken as a point 0, and the corrected image is adjusted. Therefore, the image is adjusted and corrected through relative position change, and the radioactive interference is reduced.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:
fig. 1 is a schematic diagram of a reference 0 point position and an interface junction B position in an image obtained by a characterization method according to an embodiment of the present invention;
FIG. 2 is a graph of a fission gas Xe elemental distribution obtained using a characterization method provided by an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.
At present, an electronic probe technology is adopted to perform characterization research on the diffusion behavior of fission gas products of a strong radioactive fuel element, but in the characterization process, the sample loading process of a sample is in a non-shielding state, and overhigh dose is generated for experimenters; and because the sample loading process belongs to the fine operation, if the sample loading is carried out in the shielding glove box, the fine operation can not be carried out, and the sample loading process can not meet the analysis requirement.
In order to solve the above problems, embodiments of the present invention provide a method for characterizing the diffusion behavior of a fission gas product of a strong radioactive fuel element, the method comprising performing electron probe loading and post-loading tests on a radioactive fuel sample to obtain the migration diffusion behavior of the fission gas element of the fuel element;
the sample loading process comprises the following steps:
(1) Sample stage pretreatment: fixing the sample clamping seat on a sample table before sample loading by using the sample clamping seat as a sample fixing structure, and adjusting the height of the sample clamping seat to be matched with the size of the pole shoe of the electronic probe;
(2) Sample loading: and fixing the sample in the notch of the sample clamping seat in the shielding glove box, pushing the sample into an electron microscope cabin for vacuumizing, and standing to finish sample loading.
In the sample loading process, the sample stage pretreatment process comprises the fixing of the sample clamping seat and the height adjustment of the sample clamping seat, a sample is not installed and is not irradiated when the processes are carried out, and the process belongs to fine operation and can be accurately finished; the sample loading process only fixes the sample in the notch, so that the operation is simple, fine treatment is not needed, the time consumption is short, the sample loading process can be completed in a shielding glove, and the irradiation to operators is extremely small.
Therefore, the method adopts a mode of pre-fixing and adjusting the sample clamping seat in the sample loading process, and mainly concentrates a preparation link in the operation in the sample loading process, and the sample loading can be completed only by placing the sample in the sample clamping seat, so that the long-time close-distance contact of the radioactive sample is avoided, the radioactive dose borne by personnel is greatly reduced, the damage to characterization equipment and the pollution to the working environment are also greatly reduced, the sample loading difficulty in the research of the fission gas product diffusion behavior of the fuel assembly is reduced, and the research is not restricted.
Further, fixing the sample clamping seat on the sample table by adopting conductive adhesive, adhering the conductive adhesive to the bottom of the sample clamping seat, forming a notch in the middle of the upper end of the sample clamping seat, wherein the notch can be a circular groove, and adjusting the height of the sample clamping seat by adopting a gasket between the conductive adhesive and the sample clamping seat; further preferably, the gaskets are bonded by conductive adhesive to fix the gaskets and achieve good conductive performance; the thickness of gasket is preferably 0.5mm, and the gasket is the circular piece, and the diameter of gasket matches the diameter of sample, the gasket is aluminium matter material, and the sample cassette can be copper matter material.
Further, the sample stage pretreatment process further comprises: before sample loading, the original sample fixing device of the electronic probe equipment is disassembled to fix the sample clamping seat at the position; meanwhile, conductive carbon adhesive is adhered in the notch of the sample clamping seat to fix the sample, the size of the notch is matched with the diameter of the sample, and the sample is placed in the notch and can be fastened in the notch by the adhesion of the conductive carbon adhesive when the sample is loaded;
in the sample stage pretreatment process, one ends of the copper conductive adhesives are pre-bonded on the outer side surface of the sample clamping seat, and the other ends of the copper conductive adhesives are directly connected with the sample when the sample is loaded in the glove box, so that the conductivity of the sample is improved.
Further, during the characterization test of the test specimen, the interfacial bonding area of the fuel particles and the core alloy was analyzed to compare the fissile element distribution to the elemental distribution of the fuel elements themselves.
An interface bonding area is selected as a characterization area, the interface bonding area is a key area for crack initiation and propagation and fuel failure, the interface bonding area comprises a fuel phase and a core body alloy phase, elements have obvious chemical potential change in the area, a driving force is provided for diffusion, and the diffusion phenomenon is obvious; therefore, other areas do not need to be represented blindly, the representing time can be greatly shortened, and the representing parameters can be selected reasonably and efficiently.
Meanwhile, as the content of fission nuclide in the fuel element is usually less than 1%, and strong signal interference caused by radiation released by the fuel element can easily cause difficulty in obtaining a reliable characterization result, how to eliminate background signals generated by radioactivity is still to be researched; in the embodiment of the invention, when the characterization is carried out, the fissile element distribution and the element distribution of the fuel elements are characterized at the same time, so that the distribution of the fissile elements takes the element distribution of the fuel elements as reference, the radioactive interference can be reduced, and the diffusion information of the fissile gas elements in the irradiation process of the fuel sample can be effectively and accurately obtained.
Furthermore, in the process of carrying out characterization test on the test sample, the distribution of the fissile elements and the core alloy is measured at the interface combination position of the fuel phase of the fuel element and the core alloy, and the migration diffusion behavior of the fission gas elements is characterized by the relative position change of the distribution of the fissile elements and the core alloy. Therefore, the distribution of the composition elements of the core alloy is taken as a reference, the migration and diffusion behaviors of the variable gas elements are represented through the change of the relative position, the background signal generated by radioactivity can be eliminated, the interference of the radioactivity is reduced, and the image acquisition is more accurate.
Further, performing surface scanning and line scanning analysis on the interface bonding area under a certain magnification to obtain an element distribution diagram of the fission element and the core alloy, and performing combined drawing on the element distribution diagram of the fission element and the fuel element to obtain the relative position change of the element distribution. Specifically, the combined drawing may adopt the prior art, for example, in an image processing software dedicated to an electronic probe device, an element distribution map of obtained fission elements and core alloy constituent elements is imported into the software dedicated to the electronic probe device to obtain a combined image, so that by observing and comparing the combined image, a change in position of the fission element distribution relative to the constituent element distribution of the core alloy can be known, and thus, a diffusion behavior of a fission gas product can be known.
Further, by adjusting the contrast of the secondary electron morphology image, an interface combination characteristic area of a fuel phase of the fuel element and the core alloy is searched; after the interface combination characteristic region is found, performing surface scanning and line scanning on the interface combination position, and adjusting the contrast of a fission gas element distribution image by taking a core alloy far away from a fuel phase in the scanning region as a reference 0 point, adjusting a correction image, reducing radioactive interference, improving the accuracy of image acquisition, and obtaining a surface distribution image and a line distribution image of fission gas elements; with simultaneous availability of fuel element constituent elementsAnd combining and drawing the surface distribution and the line distribution image of the fission gas elements and the surface distribution and the line distribution image of the fuel element composition elements. In the scanning area, the core alloy at the distance of 30-40 microns is selected by taking the core alloy at the distance of 30-40 microns from the interface joint as a reference 0 point, so that the diffusion interference of the core alloy can be avoided, and meanwhile, the interference of other fuel phases can not be caused, so that the obtained result is more accurate. As shown in FIG. 1, when the interface bonding area is scanned, the contrast content of the image at the A position in the scanned image is XAThe B position is at the interface combination position, and the image contrast at the B position is XBAnd taking the core alloy at the point A as a reference point 0, adjusting the image contrast at the position B, namely X = XB-XA。
Further, the magnification is 2000 times. The interface binding characteristic region can be accurately observed at the magnification.
In addition, in the research of the diffusion behavior of fission gas products of strong radioactive fuel elements, a characterization sample needs to be prepared firstly, and the sample is obtained through inlaying, polishing and coating treatment. And in the sample loading process, the prepared sample is transferred into the glove box in a shielding transfer mode.
In summary, embodiments of the present invention, first, reduce the radioactive dose to which personnel are subjected during characterization. The mode that adopts concave copper sample cassette of preparing in advance at dress appearance in-process, the preparation link that the operation that will dress appearance in-process was mainly concentrated is followed closely through shielding glove box at dress appearance in-process, only needs to compress tightly conductive adhesive and can accomplish dress appearance, avoids long-time closely contact radioactive sample, very big reduction the radioactive dose that personnel received. And secondly, the diffusion information of the fission gas elements in the irradiation process of the fuel sample can be effectively obtained. The method comprises the steps of measuring the fission elements and the core alloy at the interface of a fuel phase and the core alloy, combining the fission elements and the core alloy, and reacting the diffusion behavior of the fission gas elements by the relative position change of the fission elements and the core alloy; meanwhile, the fissile element content contrast of the core alloy micro-area far away from the fuel phase is taken as a point 0, and the corrected image is adjusted. Therefore, the relative position is changed, the corrected image is adjusted, and the radioactive interference is reduced.
The following description is given by way of specific examples.
Taking a diffusion characterization method of fission gas elements of a highly radioactive U — Mo fuel element as an example, the following procedure was studied.
1. Sample preparation
a) Cutting the nuclear fuel elements into small pieces in the thermal chamber to obtain samples with the size of about 6mm x 3mm x 2mm, so as to reduce the surface dosage (the dosage is too high when the dosage is too large, and the clamping is influenced when the dosage is too small, so that the remote operation of a mechanical arm in the thermal chamber is not facilitated);
b) Inlaying a sample by adopting Pb-Bi-Sn high atomic number alloy with the melting point of 140 ℃ in a hot chamber, grinding for 5min by adopting 200, 600 and 1200-mesh grinding discs under the pressure of 35N, 30N and 25N respectively, and polishing for 10min by using 9 mu, 3 mu and 1 mu diamond suspensions under the pressure of 20N, 15N and 10N;
c) And coating the film for 30s by using a vacuum evaporator to complete the preparation of the sample.
Among them, pb-Bi-Sn high atomic number alloys having a melting point of 140 ℃ are commercially available, and diamond suspensions are also commercially available, for example, from Stell corporation.
2. Sample preparation
Transferring the prepared sample to an exchange chamber by using a manipulator and a transfer trolley in a hot chamber; and then transporting the sample to an electron microscope laboratory by using a closed lead barrel with the thickness of not less than 3 cm. And before the experiment, a negative pressure ventilator in the laboratory is opened to reduce the pollution influence of sample radionuclide volatilization on the laboratory environment.
3. Sample stage pretreatment
Preparing and inlaying sample diameter in advance
And a concave copper sample clamping seat with the height (20 mm) matched, and a test sample is placed in the notch. Before sample loading, the original sample fixing device of the electronic probe equipment is firstly detached, and the clamping seat is fixed on the sample table by using conductive adhesive and is pre-usedThe height of the aluminum gaskets is adjusted, the gaskets are bonded by conductive adhesive, and the thickness of each gasket is 0.5mm; at least 6 conductive carbon glues are pasted in the notch of the sample clamping seat along different directions for fixing a sample, 1-3 conductive copper glues are pasted on the outer side surface of the sample clamping seat, and one end of each conductive copper glue is pasted on the outer side of the sample clamping seat.
The process has no radioactivity, can be efficiently and quickly completed, and avoids complex sample loading operation in a glove box.
4. Sample loading
After the sample is led into the shielding glove box, place the sample in the notch of sample cassette and compress tightly for the lower bottom surface of sample is connected electrically conductive carbon and is glued fixedly, uses tweezers to press electrically conductive copper and glues again, makes the upper surface of electrically conductive copper glue's other end connection sample (the electrically conductive copper is glued and partial sample lug connection best), then pushes the interior evacuation of electron microscope cabin, stews 2 hours so that electrically conductive glue and the bonding surface degassing solidification of sample, can accomplish the dress appearance.
Only need place the sample in the notch and compress tightly at this in-process, make under the sample bottom surface connect the conductive carbon glue fix, the other end of upper surface connection conductive copper glue can, whole process does not relate to the operation that becomes more meticulous, and easy operation, greatly reduced the irradiation to operating personnel.
5. Characterization measurement, data processing
Regulating the contrast of secondary electron morphology images, searching characteristic areas such as interfaces of fuel phases and core body alloys, and performing spectral surface distribution and line distribution scanning characterization on typical fission gas elements under 2000 times; and adjusting the contrast of the image by taking the core alloy far away from the fuel phase in the scanning area as a reference 0 point to obtain a surface distribution and line distribution image of the fission gas element. And meanwhile, performing scanning characterization on the spectral surface distribution and the line distribution of the fuel element constituent elements under the condition of 2000 times to obtain a surface distribution image and a line distribution image of the fuel element constituent elements. Combining and drawing the images of the two images to obtain the relative position change of element distribution; the diffusion behavior and rule of fission gas products can be obtained according to the change of the relative position.
In the process, the contrast subtraction method is used for reducing the radioactive interference. The fission gas element distribution is characterized by being multiplied by 2000, the concentration of Xe element in a region where a core alloy which is 30-40 mu m away from a fuel phase and away from an interface joint is located is defined as 0, surface scanning analysis is carried out on the region, image contrast characteristics of the Xe element distribution are obtained, the image contrast is used as a zero point of the contrast to adjust the image contrast, surface distribution and line distribution images of the fission gas element are obtained, and radioactive interference factors are eliminated.
As shown in FIG. 2, elemental profiles from a face scan of a fission gas Xe element obtained using the characterization method described above. The figure clearly shows the Xe element distribution in the strongly radioactive fuel element after irradiation, i.e. the fuel phase edge region content is higher than the middle region of the fuel phase, indicating the tendency of the Xe element to accumulate at the phase interface of the fuel phase and the alloy. The acquisition of this data indicates the reliability of the characterization method provided by the present invention.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. A strong radioactive fuel element fission gas product diffusion behavior characterization method is characterized by comprising the steps of loading a radioactive fuel sample by an electronic probe, and testing after loading the sample to obtain the migration diffusion behavior of the fission gas element of a fuel element;
the sample loading process comprises the following steps:
(1) Sample stage pretreatment: fixing the sample clamping seat on a sample table before sample loading by taking the sample clamping seat as a sample fixing structure, and adjusting the height of the sample clamping seat to be matched with the size of a pole shoe of an electronic probe;
(2) Sample loading: and fixing the sample in the notch of the sample clamping seat in the shielding glove box, pushing the sample into an electron microscope cabin for vacuumizing, and standing to finish sample loading.
2. The method of characterizing diffusion behavior of a fission gas product of a strongly radioactive fuel element as claimed in claim 1, wherein a sample holder is fixed to the sample stage by means of a conductive adhesive, and a spacer is provided between said conductive adhesive and said sample holder for adjusting the height of said sample holder.
3. A method of characterizing the diffusion behavior of fission gas products of a highly radioactive fuel element as claimed in claim 2, wherein said spacers are bonded together by conductive adhesive, and have a thickness of 0.5mm, and have a diameter matching the diameter of the specimen, and are made of aluminum.
4. A method of characterizing the diffusion behavior of a highly radioactive fuel element fission gas product as claimed in claim 1, wherein the sample stage pretreatment process further comprises: before sample loading, the original sample fixing device of the electronic probe equipment is disassembled to fix the sample clamping seat; adhering conductive carbon adhesive in the notch of the sample clamping seat to fix the sample;
in the sample stage pretreatment process, one ends of the copper conductive adhesives are pre-bonded on the outer side surface of the sample clamping seat, and the other ends of the copper conductive adhesives are connected with the sample when the sample is loaded in the glove box, so that the conductivity of the sample is improved.
5. A method of characterizing the diffusion behavior of a fission gas product of a highly radioactive fuel element as claimed in claim 1, wherein during said characterization test the area of interfacial bonding between the fuel particles and the core alloy is analyzed so that the fissile element distribution is referenced against the elemental distribution of the fuel element itself.
6. The method of characterizing diffusion behavior of a fission gas product of a highly radioactive fuel element according to claim 1, wherein during the characterization test of the sample, the distribution of the constituent elements of the fissile element and the core alloy is measured at the interface junction of the fuel phase of the fuel element and the core alloy, and the migration diffusion behavior of the fissile element is characterized by the change in the relative position of the distribution of the constituent elements of the fissile element and the core alloy.
7. A method of characterizing the diffusion behavior of a highly radioactive fuel element fission gas product as claimed in claim 6, wherein said interface bonding region is analyzed by surface scanning and line scanning at a magnification to obtain elemental profiles of the constituent elements of the fissile element and core alloy, and the obtained elemental profiles of the fissile element and the fuel element constituent elements are plotted in combination to obtain the relative positional variation of the elemental profiles.
8. The method of characterizing fission gas product diffusion behavior of a highly radioactive fuel element according to claim 7, wherein the characteristic region of interface bonding between the fuel phase of the fuel element and the core alloy is found by adjusting secondary electron topographic image contrast;
after surface scanning and line scanning are carried out, the contrast of the fission gas element distribution image is adjusted by taking the core alloy far away from the fuel phase in the scanning area as a reference point 0, and the surface distribution and line distribution images of the fission gas elements are obtained to be combined and drawn with the obtained element distribution map of the fuel element composition elements.
9. A method of characterizing fission gas product diffusion behavior for a highly radioactive fuel element as claimed in claim 8, wherein said core alloy as reference point 0 is at a distance of 30 μm to 40 μm from the interface junction.
10. A method of characterizing fission gas product diffusion behavior of a strongly radioactive fuel element as claimed in claim 7, wherein said magnification is 2000 x.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210908933.5A CN115266795A (en) | 2022-07-29 | 2022-07-29 | Method for representing diffusion behavior of fission gas product of strong radioactive fuel element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210908933.5A CN115266795A (en) | 2022-07-29 | 2022-07-29 | Method for representing diffusion behavior of fission gas product of strong radioactive fuel element |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115266795A true CN115266795A (en) | 2022-11-01 |
Family
ID=83748047
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210908933.5A Pending CN115266795A (en) | 2022-07-29 | 2022-07-29 | Method for representing diffusion behavior of fission gas product of strong radioactive fuel element |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115266795A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116487079A (en) * | 2023-04-03 | 2023-07-25 | 中国核动力研究设计院 | Method for qualitatively testing nuclear fuel microcell burnup based on electronic probe |
Citations (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11304732A (en) * | 1998-04-16 | 1999-11-05 | Jeol Ltd | Method for identifying analysis element by surface-analyzing equipment |
| JP2000235009A (en) * | 1999-02-16 | 2000-08-29 | Jeol Ltd | Particle analyzing device by means of electron probe microanalyzer |
| JP2003017539A (en) * | 2001-06-28 | 2003-01-17 | Hitachi Ltd | Method of observing atom diffusion within metal wiring |
| CN1688375A (en) * | 2002-08-21 | 2005-10-26 | 先进能源科技公司 | Ex-situ PEM fuel cell testing: towards visualizing gas diffusion |
| CN202230039U (en) * | 2011-09-14 | 2012-05-23 | 中国航空工业集团公司北京航空材料研究院 | Sample bearing and position adjusting bracket used in electron probe tests |
| CN103454300A (en) * | 2013-09-06 | 2013-12-18 | 鞍钢股份有限公司 | Electronic probe line analysis quantitative test method of ultra-light element carbon |
| CN104089969A (en) * | 2014-07-18 | 2014-10-08 | 山西太钢不锈钢股份有限公司 | Method for evaluating high-temperature diffusion effect of alloyed tool mold steel |
| CN105928814A (en) * | 2016-04-15 | 2016-09-07 | 武汉理工大学 | Asphalt mixture penetrating type water steam diffusion coefficient detection method |
| CN106814176A (en) * | 2015-12-02 | 2017-06-09 | 北京有色金属研究总院 | A kind of screening design method of beryllium copper elastic alloy alternative materials |
| CN107290199A (en) * | 2017-08-10 | 2017-10-24 | 南京钢铁股份有限公司 | A kind of method that utilization electron probe quickly characterizes bearing steel segregation |
| CN107766641A (en) * | 2017-10-16 | 2018-03-06 | 中国核动力研究设计院 | One kind calculates UO2The method of fuel fission gas rate of heat release |
| CN109448878A (en) * | 2018-11-13 | 2019-03-08 | 中国核动力研究设计院 | The vacuum mosaic technology of sample after a kind of irradiation |
| CN210221874U (en) * | 2019-03-27 | 2020-03-31 | 广东韶钢松山股份有限公司 | Electronic probe sample seat capable of adjusting sample height and angle |
| CN210742166U (en) * | 2019-05-27 | 2020-06-12 | 江阴兴澄特种钢铁有限公司 | Electronic probe sample table |
| CN111965212A (en) * | 2020-07-31 | 2020-11-20 | 南方科技大学 | Thermophysical property calculation method, thermophysical property test system, electronic device, and storage medium |
| CN212845122U (en) * | 2020-08-03 | 2021-03-30 | 武汉上谱分析科技有限责任公司 | Multifunctional sample table for electronic probe test |
| CN112630248A (en) * | 2020-12-16 | 2021-04-09 | 东北大学 | Method for determining microsegregation ratio of casting blank |
| CN112632839A (en) * | 2020-11-30 | 2021-04-09 | 中国核动力研究设计院 | Speed theory-based method for simulating radiation hardening in zirconium-based alloy and model system |
| CN112904048A (en) * | 2021-03-06 | 2021-06-04 | 苏州青云瑞晶生物科技有限公司 | Method for adjusting center position of transmission electron microscope sample |
| CN215833296U (en) * | 2021-07-27 | 2022-02-15 | 中国科学院高能物理研究所 | Test platform |
| CN114216754A (en) * | 2021-12-28 | 2022-03-22 | 松山湖材料实验室 | Gradient component amorphous alloy sample and high-flux preparation method thereof |
| CN114518376A (en) * | 2022-02-18 | 2022-05-20 | 中国核动力研究设计院 | Electronic probe shielding sample seat of radioactive sample |
| CN114743607A (en) * | 2022-03-31 | 2022-07-12 | 西安交通大学 | Method for calculating fission gas release and irradiation swelling behaviors in nuclear fuel |
-
2022
- 2022-07-29 CN CN202210908933.5A patent/CN115266795A/en active Pending
Patent Citations (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11304732A (en) * | 1998-04-16 | 1999-11-05 | Jeol Ltd | Method for identifying analysis element by surface-analyzing equipment |
| JP2000235009A (en) * | 1999-02-16 | 2000-08-29 | Jeol Ltd | Particle analyzing device by means of electron probe microanalyzer |
| JP2003017539A (en) * | 2001-06-28 | 2003-01-17 | Hitachi Ltd | Method of observing atom diffusion within metal wiring |
| CN1688375A (en) * | 2002-08-21 | 2005-10-26 | 先进能源科技公司 | Ex-situ PEM fuel cell testing: towards visualizing gas diffusion |
| CN202230039U (en) * | 2011-09-14 | 2012-05-23 | 中国航空工业集团公司北京航空材料研究院 | Sample bearing and position adjusting bracket used in electron probe tests |
| CN103454300A (en) * | 2013-09-06 | 2013-12-18 | 鞍钢股份有限公司 | Electronic probe line analysis quantitative test method of ultra-light element carbon |
| CN104089969A (en) * | 2014-07-18 | 2014-10-08 | 山西太钢不锈钢股份有限公司 | Method for evaluating high-temperature diffusion effect of alloyed tool mold steel |
| CN106814176A (en) * | 2015-12-02 | 2017-06-09 | 北京有色金属研究总院 | A kind of screening design method of beryllium copper elastic alloy alternative materials |
| CN105928814A (en) * | 2016-04-15 | 2016-09-07 | 武汉理工大学 | Asphalt mixture penetrating type water steam diffusion coefficient detection method |
| CN107290199A (en) * | 2017-08-10 | 2017-10-24 | 南京钢铁股份有限公司 | A kind of method that utilization electron probe quickly characterizes bearing steel segregation |
| CN107766641A (en) * | 2017-10-16 | 2018-03-06 | 中国核动力研究设计院 | One kind calculates UO2The method of fuel fission gas rate of heat release |
| CN109448878A (en) * | 2018-11-13 | 2019-03-08 | 中国核动力研究设计院 | The vacuum mosaic technology of sample after a kind of irradiation |
| CN210221874U (en) * | 2019-03-27 | 2020-03-31 | 广东韶钢松山股份有限公司 | Electronic probe sample seat capable of adjusting sample height and angle |
| CN210742166U (en) * | 2019-05-27 | 2020-06-12 | 江阴兴澄特种钢铁有限公司 | Electronic probe sample table |
| CN111965212A (en) * | 2020-07-31 | 2020-11-20 | 南方科技大学 | Thermophysical property calculation method, thermophysical property test system, electronic device, and storage medium |
| CN212845122U (en) * | 2020-08-03 | 2021-03-30 | 武汉上谱分析科技有限责任公司 | Multifunctional sample table for electronic probe test |
| CN112632839A (en) * | 2020-11-30 | 2021-04-09 | 中国核动力研究设计院 | Speed theory-based method for simulating radiation hardening in zirconium-based alloy and model system |
| CN112630248A (en) * | 2020-12-16 | 2021-04-09 | 东北大学 | Method for determining microsegregation ratio of casting blank |
| CN112904048A (en) * | 2021-03-06 | 2021-06-04 | 苏州青云瑞晶生物科技有限公司 | Method for adjusting center position of transmission electron microscope sample |
| CN215833296U (en) * | 2021-07-27 | 2022-02-15 | 中国科学院高能物理研究所 | Test platform |
| CN114216754A (en) * | 2021-12-28 | 2022-03-22 | 松山湖材料实验室 | Gradient component amorphous alloy sample and high-flux preparation method thereof |
| CN114518376A (en) * | 2022-02-18 | 2022-05-20 | 中国核动力研究设计院 | Electronic probe shielding sample seat of radioactive sample |
| CN114743607A (en) * | 2022-03-31 | 2022-07-12 | 西安交通大学 | Method for calculating fission gas release and irradiation swelling behaviors in nuclear fuel |
Non-Patent Citations (4)
| Title |
|---|
| 何力;刘克加;伍玉娇;朱取成;: "发射光谱分析过程中试样表面结构及成份的变化", 贵州工业大学学报(自然科学版), no. 01, 2 April 1987 (1987-04-02), pages 105 - 109 * |
| 冯柳;: "电子探针在金属材料分析中的应用研究", 中国金属通报, no. 07, 15 July 2020 (2020-07-15), pages 185 - 186 * |
| 许咏丽, 龙斌, 李军刚: "吸氧材料对快堆元件包壳内壁腐蚀的抑制作用", 核科学与工程, no. 04, 30 December 1996 (1996-12-30), pages 323 - 330 * |
| 许悦红;张学迁;王球;田震;谷建强;欧阳春梅;路鑫超;张文涛;韩家广;张伟力;: "基于光导微探针的近场/远场可扫描太赫兹光谱技术", 物理学报, no. 03, 28 December 2015 (2015-12-28), pages 036803 - 1 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116487079A (en) * | 2023-04-03 | 2023-07-25 | 中国核动力研究设计院 | Method for qualitatively testing nuclear fuel microcell burnup based on electronic probe |
| CN116487079B (en) * | 2023-04-03 | 2024-01-30 | 中国核动力研究设计院 | Method for qualitatively testing nuclear fuel microcell burnup based on electronic probe |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Li et al. | Recent advances in FIB–TEM specimen preparation techniques | |
| Lawes | Scanning electron microscopy and X-ray microanalysis | |
| Otto et al. | In situ investigation of lithium metal–solid electrolyte anode interfaces with ToF‐SIMS | |
| CN110057684B (en) | Thermoelectric electric coupling sample stage based on in-situ observation experiment | |
| Blum et al. | Solid and liquid spectroscopic analysis (SALSA)–a soft x-ray spectroscopy endstation with a novel flow-through liquid cell | |
| CN115266795A (en) | Method for representing diffusion behavior of fission gas product of strong radioactive fuel element | |
| JP7483735B2 (en) | Battery box | |
| Odom et al. | Quantitative image acquisition system for ion microscopy based on the resistive anode encoder | |
| Myhre et al. | Samarium thin films molecular plated from N, N-dimethylformamide characterized by XPS | |
| CN113804714A (en) | Electrochemical energy storage model device suitable for in-situ online surface characterization and application | |
| JPH06232238A (en) | Method and apparatus for sample processing | |
| Aguiar et al. | Densification of graphite under high pressure and moderate temperature | |
| Tateno et al. | The advanced ion-milling method for preparation of thin film using ion slicer: application to a sample recovered from diamond-anvil cell | |
| Williams et al. | Analytical electron microscopy | |
| Bolshakova et al. | Resistance of Hall sensors based on graphene to neutron radiation | |
| CN216525539U (en) | EBSD sample holder of radioactive sample | |
| CN219302321U (en) | All-solid-state lithium ion in-situ testing device | |
| CN106483380A (en) | Particle irradiation sample electrical conductivity and the method for testing of resistivity | |
| CN215770555U (en) | High-low temperature control ion irradiation target | |
| Huiying et al. | Element distributions and quantitative analysis of a single cell by micro-PIXE and synchrotron radiation XRF | |
| Ma et al. | An improved preparation method for cross‐sectional TEM specimens of films deposited on metallic substrates | |
| Mukhopadhyay et al. | Revisiting W–ZrC interfaces: A first principles study | |
| Johari et al. | SAMPLE PREPARATION FOR SCANNING ELECTRON MICROSCOPE METALLOGRAPHY. | |
| Kaloyeros et al. | Study by Extended X‐ray Absorption Fine Structure Technique and Microscopy of the Amorphous State of Titanium Diboride Thin Films | |
| Minier | Microscopic examination of the behavior of non-conductive optical solar reflectors after electrical breakdown |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |