To improve the mechanical properties of the Y_(2)O_(3)-added W alloy,Mo and Zr were independently added to a sample of W-Y_(2)O_(3).In this study,the effects of minor additions of elemental Mo and Zr on He bubble form...To improve the mechanical properties of the Y_(2)O_(3)-added W alloy,Mo and Zr were independently added to a sample of W-Y_(2)O_(3).In this study,the effects of minor additions of elemental Mo and Zr on He bubble formation in the Y_(2)O_(3)added W alloys were investigated at 773 K,973 K,and 1173 K,where the maximum irradiation fluence of the samples using 5 keV He ions was 1.8×10^(21) He m^(−2).He bubbles were observed at all temperatures for both alloys;however,the irradiation fluences at which He bubbles could be observed differed at each temperature.With increase in irradiation temperature,the He irradiation fluence for which the formation of He bubbles could be observed decreased.At the relatively low temperature of 773 K,the void swelling in the W-Mo-Y_(2)O_(3)and W-Zr-Y_(2)O_(3)alloys was slightly lower than that of W-Y_(2)O_(3)alloy.However,at high temperature of 973 K and 1173 K,the He irradiation resistances of both W-Mo-Y_(2)O_(3)and W-Zr-Y_(2)O_(3)were worse than that of W-Y_(2)O_(3).The addition of Zr enhanced the interaction between vacancies and He,enhancing the formation of He bubbles.However,the addition of Mo coarsened the Y_(2)O_(3)particles,reducing the suppression of vacancy cluster formation due to the dispersion of Y_(2)O_(3)particles.It is,therefore,necessary to fully consider mechanical properties and T-retention in addition to the irradiation resistance of He to select an alloy as the plasma-facing material for fusion applications.展开更多
To investigate the surface damage of a material by He ions,a dispersion-strengthened W-1wt%TiC alloy was irradiated by 5-keV He ions at 773 K,973 K,and 1173 K up to an ion dose of 1.8×10^(21)He m−2,respectively.N...To investigate the surface damage of a material by He ions,a dispersion-strengthened W-1wt%TiC alloy was irradiated by 5-keV He ions at 773 K,973 K,and 1173 K up to an ion dose of 1.8×10^(21)He m−2,respectively.No He bubble formation was observed under transmission electron microscopy at any temperature for He doses less than 1.5×10^(20)He m^(−2).When this dose was exceeded,He bubbles grew and void swelling increased with increasing irradiation doses.Naturally,the growth of He bubbles and the void swelling became more pronounced with increasing irradiation temperatures.Compared to the published data on commercially available pure W,the formation of He bubbles was suppressed by TiC particles in the W-TiC alloy,especially at low doses.展开更多
基金The study is financially supported by JSPS KAKENHI(Grant No.JP20K03900).
文摘To improve the mechanical properties of the Y_(2)O_(3)-added W alloy,Mo and Zr were independently added to a sample of W-Y_(2)O_(3).In this study,the effects of minor additions of elemental Mo and Zr on He bubble formation in the Y_(2)O_(3)added W alloys were investigated at 773 K,973 K,and 1173 K,where the maximum irradiation fluence of the samples using 5 keV He ions was 1.8×10^(21) He m^(−2).He bubbles were observed at all temperatures for both alloys;however,the irradiation fluences at which He bubbles could be observed differed at each temperature.With increase in irradiation temperature,the He irradiation fluence for which the formation of He bubbles could be observed decreased.At the relatively low temperature of 773 K,the void swelling in the W-Mo-Y_(2)O_(3)and W-Zr-Y_(2)O_(3)alloys was slightly lower than that of W-Y_(2)O_(3)alloy.However,at high temperature of 973 K and 1173 K,the He irradiation resistances of both W-Mo-Y_(2)O_(3)and W-Zr-Y_(2)O_(3)were worse than that of W-Y_(2)O_(3).The addition of Zr enhanced the interaction between vacancies and He,enhancing the formation of He bubbles.However,the addition of Mo coarsened the Y_(2)O_(3)particles,reducing the suppression of vacancy cluster formation due to the dispersion of Y_(2)O_(3)particles.It is,therefore,necessary to fully consider mechanical properties and T-retention in addition to the irradiation resistance of He to select an alloy as the plasma-facing material for fusion applications.
基金the auspices of the NIFS Collaboration Research Program(Grant No.NIFS17KLPF055).
文摘To investigate the surface damage of a material by He ions,a dispersion-strengthened W-1wt%TiC alloy was irradiated by 5-keV He ions at 773 K,973 K,and 1173 K up to an ion dose of 1.8×10^(21)He m−2,respectively.No He bubble formation was observed under transmission electron microscopy at any temperature for He doses less than 1.5×10^(20)He m^(−2).When this dose was exceeded,He bubbles grew and void swelling increased with increasing irradiation doses.Naturally,the growth of He bubbles and the void swelling became more pronounced with increasing irradiation temperatures.Compared to the published data on commercially available pure W,the formation of He bubbles was suppressed by TiC particles in the W-TiC alloy,especially at low doses.
