We report on cavity swelling at peak damage regions of three ferritic-martensitic(FM)steels(NHS,RAFM and T91)irradiated by 196 MeV Kr ions at different temperatures(450/550℃).Cavity configurations of the irradiated s...We report on cavity swelling at peak damage regions of three ferritic-martensitic(FM)steels(NHS,RAFM and T91)irradiated by 196 MeV Kr ions at different temperatures(450/550℃).Cavity configurations of the irradiated specimens are investigated by transmission electron microscopy with cross-section technique.For home-made reduced activation ferritic-martensitic(RAFM)and T91 steels irradiated at 450℃,both large size and bimodal size distribution of the cavity are found in their peak damage regions,whereas novel high silicon(NHS)steel exhibits good swelling resistance at different irradiation temperatures.Temperature relativity of the cavity swelling in NHS,RAFM and T91 steels is discussed briefly.展开更多
The effects of 100 keV H-ion implantation on the structure of LiTaO3 crystal are investigated by Raman and UV/VIS/NIR spectroscopies.The implantation fluence is in the range from 1.0 × 10^(13) to 1.0 × 10^(1...The effects of 100 keV H-ion implantation on the structure of LiTaO3 crystal are investigated by Raman and UV/VIS/NIR spectroscopies.The implantation fluence is in the range from 1.0 × 10^(13) to 1.0 × 10^(17) H^(+)/cm^(2).The experimental results show the dependence of the crystal structure on ion fluence.It is found that the structural modification of the LiTaO3 crystal is due to two processes.One is H-ions occupying lithium vacancies (VLi),which is predominant at a fluence less than 1.0 × 10^(14) H^(+) /cm^(2).This process causes the reduction of negative charge centers in the crystal and relaxation of distortion in the local lattice structure.The other is the influence of defects created during implantation,which plays a dominant role gradually in the structural modification at a fluence larger than 1.0 × 10^(15) H^(+)/cm^(2).展开更多
Evolutions of defects and helium contained defects produced by atomic displacement and helium deposition with helium implantation at different temperatures in novel high silicon （NHS） steel are investigated by a slo...Evolutions of defects and helium contained defects produced by atomic displacement and helium deposition with helium implantation at different temperatures in novel high silicon （NHS） steel are investigated by a slow positron beam. Differences of the defect information among samples implanted by helium to a fluence of 1×1017 ions/cm2 at room temperature, 300°C, 450°C and 750°C are discussed. It is found that the mobility of vacancies and vacancy clusters, a recombination of vacancy-type defects and the formation of the He-V complex lead to the occurrence of these differences. At high temperature irradiations, a change of the diffusion mechanism of He atoms/He bubbles might be one of the reasons for the change of the S-parameter.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2010CB832902the National Natural Science Foundation of China under Grant Nos 91026002,91126011 and 11275005。
文摘We report on cavity swelling at peak damage regions of three ferritic-martensitic(FM)steels(NHS,RAFM and T91)irradiated by 196 MeV Kr ions at different temperatures(450/550℃).Cavity configurations of the irradiated specimens are investigated by transmission electron microscopy with cross-section technique.For home-made reduced activation ferritic-martensitic(RAFM)and T91 steels irradiated at 450℃,both large size and bimodal size distribution of the cavity are found in their peak damage regions,whereas novel high silicon(NHS)steel exhibits good swelling resistance at different irradiation temperatures.Temperature relativity of the cavity swelling in NHS,RAFM and T91 steels is discussed briefly.
基金Supported by the National Basic Research Program of China under Grant No 2010CB832902the National Natural Science Foundation of China(10835010)the Chinese Academy of Sciences.
文摘The effects of 100 keV H-ion implantation on the structure of LiTaO3 crystal are investigated by Raman and UV/VIS/NIR spectroscopies.The implantation fluence is in the range from 1.0 × 10^(13) to 1.0 × 10^(17) H^(+)/cm^(2).The experimental results show the dependence of the crystal structure on ion fluence.It is found that the structural modification of the LiTaO3 crystal is due to two processes.One is H-ions occupying lithium vacancies (VLi),which is predominant at a fluence less than 1.0 × 10^(14) H^(+) /cm^(2).This process causes the reduction of negative charge centers in the crystal and relaxation of distortion in the local lattice structure.The other is the influence of defects created during implantation,which plays a dominant role gradually in the structural modification at a fluence larger than 1.0 × 10^(15) H^(+)/cm^(2).
基金Supported by the National Basic Research Program of China under Grant No 2010CB832902, and the National Natural Science Foundation of China under Grant Nos 91026002, 91126011 and 11275005.
文摘Evolutions of defects and helium contained defects produced by atomic displacement and helium deposition with helium implantation at different temperatures in novel high silicon （NHS） steel are investigated by a slow positron beam. Differences of the defect information among samples implanted by helium to a fluence of 1×1017 ions/cm2 at room temperature, 300°C, 450°C and 750°C are discussed. It is found that the mobility of vacancies and vacancy clusters, a recombination of vacancy-type defects and the formation of the He-V complex lead to the occurrence of these differences. At high temperature irradiations, a change of the diffusion mechanism of He atoms/He bubbles might be one of the reasons for the change of the S-parameter.
