β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirem...β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample preparation.However,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this technique.In this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is proposed.The average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium distributions.Furthermore,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.展开更多
Tungsten(W)is the leading plasma-facing candidate material for the International Thermonuclear Experimental Reactor and next-generation fusion reactors.The impact of synergistic helium(He),irradiation-induced microstr...Tungsten(W)is the leading plasma-facing candidate material for the International Thermonuclear Experimental Reactor and next-generation fusion reactors.The impact of synergistic helium(He),irradiation-induced microstructural changes,and the corresponding thermal-mechanical property degradation of W are critically important but are not well understood yet.Predicting the performance of W in fusion environments requires understanding the fundamentals of He-defect interactions and the resultant He bubble nucleation and growth in W.In this study,He retention in helium-ion-implanted W was assessed using neutron depth profiling(NDP),laser ablation mass spectrometry(LAMS),and thermal desorption spectroscopy(TDS)following 10 keV room-temperature He implantation at various fluences.These three experimental techniques enabled the determination of the He depth profile and retention in He-implanted W.A cluster dynamics model based on the diffusion-reaction rate theory was applied to interpret the experimental data.The model successfully predicted the He spatial depth-dependent profile in He-implanted W,which was in good agreement with the LAMS measurements.The model also successfully captured the major features of the He desorption spectra observed in the THDS measurements.The NDP quantified total He concentration values for the samples;they were similar to those estimated by LAMS.However,the depth profiles from NDP and LAMS were not comparable due to several factors.The combination of modeling and experimentation enabled the identification of possible trapping sites for He in W and the evolution of He-defect clusters during the TDS thermal annealing process.展开更多
In this paper,high-energy Ne ions were used to irradiate Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) metallic glass(MG)and crystalline W to investigate their difference in mechanical response after irradiation.The results showed t...In this paper,high-energy Ne ions were used to irradiate Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) metallic glass(MG)and crystalline W to investigate their difference in mechanical response after irradiation.The results showed that with the irradiation dose increased,the tensile micro-strain increased,nano-hardness increased from 7.11 GPa to 7.90 GPa and 8.62 GPa,Young’s modulus increased,and H3/E2 increased which indicating that the plastic deformability decreased in crystalline W.Under the same irradiation conditions,the Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG still maintained the amorphous structure and became more disordered despite the longer range and stronger displacement damage of Ne ions in Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG than in crystalline W.Unlike the irradiation hardening and embrittlement behavior of crystalline W,Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG showed the gradual decrease in hardness from 6.02 GPa to 5.89 GPa and 5.50 GPa,the decrease in modulus and the increase in plastic deformability with the increasing dose.Possibly,the irradiation softening and toughening phenomenon of Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG could provide new ideas for the design of nuclear materials.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFE03170003)the National Natural Science Foundation of China(Nos.12305403 and 12275243).
文摘β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample preparation.However,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this technique.In this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is proposed.The average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium distributions.Furthermore,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.
基金supported by the U.S.Department of EnergyOffice of Science+5 种基金Fusion Energy Sciences Programunder Contract No.DE-AC05-00OR22725 with UT-BattelleLLCfinancial support from the US Department of EnergyOffice of Fusion Energy Science under grant DOE-DE-SC000661 at The University of Tennessee-KnoxvilleJLW and HCM were funded by the National Institute of Standards and Technology。
文摘Tungsten(W)is the leading plasma-facing candidate material for the International Thermonuclear Experimental Reactor and next-generation fusion reactors.The impact of synergistic helium(He),irradiation-induced microstructural changes,and the corresponding thermal-mechanical property degradation of W are critically important but are not well understood yet.Predicting the performance of W in fusion environments requires understanding the fundamentals of He-defect interactions and the resultant He bubble nucleation and growth in W.In this study,He retention in helium-ion-implanted W was assessed using neutron depth profiling(NDP),laser ablation mass spectrometry(LAMS),and thermal desorption spectroscopy(TDS)following 10 keV room-temperature He implantation at various fluences.These three experimental techniques enabled the determination of the He depth profile and retention in He-implanted W.A cluster dynamics model based on the diffusion-reaction rate theory was applied to interpret the experimental data.The model successfully predicted the He spatial depth-dependent profile in He-implanted W,which was in good agreement with the LAMS measurements.The model also successfully captured the major features of the He desorption spectra observed in the THDS measurements.The NDP quantified total He concentration values for the samples;they were similar to those estimated by LAMS.However,the depth profiles from NDP and LAMS were not comparable due to several factors.The combination of modeling and experimentation enabled the identification of possible trapping sites for He in W and the evolution of He-defect clusters during the TDS thermal annealing process.
基金supported by National Natural Science Foundation of China(Nos.12305224,U23B2099 and 11975065)the Natural Science Foundation of Liaoning Province(No.2021-BS-223)+1 种基金the Liaoning Provincial Department of Education Youth Fund Project(No.LJKQZ20222309)supports from the National Laboratory of Heavy-ion Research Facility(HIRFL)in the Institute of Modern Physics in Lanzhou,China.
文摘In this paper,high-energy Ne ions were used to irradiate Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) metallic glass(MG)and crystalline W to investigate their difference in mechanical response after irradiation.The results showed that with the irradiation dose increased,the tensile micro-strain increased,nano-hardness increased from 7.11 GPa to 7.90 GPa and 8.62 GPa,Young’s modulus increased,and H3/E2 increased which indicating that the plastic deformability decreased in crystalline W.Under the same irradiation conditions,the Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG still maintained the amorphous structure and became more disordered despite the longer range and stronger displacement damage of Ne ions in Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG than in crystalline W.Unlike the irradiation hardening and embrittlement behavior of crystalline W,Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG showed the gradual decrease in hardness from 6.02 GPa to 5.89 GPa and 5.50 GPa,the decrease in modulus and the increase in plastic deformability with the increasing dose.Possibly,the irradiation softening and toughening phenomenon of Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG could provide new ideas for the design of nuclear materials.
