The decomposition and precipitation behaviors of a quenched Cu-15wt%Sn alloy as a function of aging temperature were investigated using transmission electron microscopy （TEM）. Focused ion beam （FIB） was employed t...The decomposition and precipitation behaviors of a quenched Cu-15wt%Sn alloy as a function of aging temperature were investigated using transmission electron microscopy （TEM）. Focused ion beam （FIB） was employed to assist TEM specimen preparation. At 300 ℃, the decomposition of the supersaturated phase occurred at grain boundaries, displaying a cellular morphology. The lamellae were found with and phases, rather than with the equilibrium e and phases. The and phases exhibit a welldefined orientation relationship （OR） as On the other hand, at 320 ℃, only incipient lamellar structures of several micron meters were observed, which were composed of the 6 and phases. At the same time, abundant intragranular precipitation of the e phase in the form of platelets was observed, and OR as （lil）J/ （001）, [110] J/[100] exists between e phase and the ct phase. These contrasting precipitation behaviors are discussed from the viewpoint of crystallographic coherency of these phases.展开更多
A type of home-made reduced activation martensitic steel, high silicon （SIMP） steel, is homogeneously irradiated with energetic Fe ions to the doses of 0.1, 0.25 and 1 displacement per atom （dpa）, respectively, at...A type of home-made reduced activation martensitic steel, high silicon （SIMP） steel, is homogeneously irradiated with energetic Fe ions to the doses of 0.1, 0.25 and 1 displacement per atom （dpa）, respectively, at 300℃ and i dpa, at 400℃. MicrostructurM changes are investigated in detail by transmission electron microscopy with cross-section technique. Interstitial defects and defect dusters induced by Fe-ion irradiation are observed in ali the specimens under different conditions. It is found that with increasing irradiation temperature, size of defect clusters increases while the density drops quickly. The results of element chemical mapping from the STEM images indicate that the Si element enrichment and Ta element depletion occur inside the precipitates in the matrix of SIMP steel irradiated to a dose of 1 dpa at 300℃. Correlations between the microstructure and irradiation conditions are briefly discussed.展开更多
基金supported by the China Scholarship Council(No.2010602038)the Ministry of Science and Technology of China(No.2010DFA51650)
文摘The decomposition and precipitation behaviors of a quenched Cu-15wt%Sn alloy as a function of aging temperature were investigated using transmission electron microscopy （TEM）. Focused ion beam （FIB） was employed to assist TEM specimen preparation. At 300 ℃, the decomposition of the supersaturated phase occurred at grain boundaries, displaying a cellular morphology. The lamellae were found with and phases, rather than with the equilibrium e and phases. The and phases exhibit a welldefined orientation relationship （OR） as On the other hand, at 320 ℃, only incipient lamellar structures of several micron meters were observed, which were composed of the 6 and phases. At the same time, abundant intragranular precipitation of the e phase in the form of platelets was observed, and OR as （lil）J/ （001）, [110] J/[100] exists between e phase and the ct phase. These contrasting precipitation behaviors are discussed from the viewpoint of crystallographic coherency of these phases.
基金Supported by the Young Scientists Fund of the National Natural Science Foundation of China under Grant No 11505246the Major Research Plan of the National Natural Science Foundation of China under Grant No 91426301
文摘A type of home-made reduced activation martensitic steel, high silicon （SIMP） steel, is homogeneously irradiated with energetic Fe ions to the doses of 0.1, 0.25 and 1 displacement per atom （dpa）, respectively, at 300℃ and i dpa, at 400℃. MicrostructurM changes are investigated in detail by transmission electron microscopy with cross-section technique. Interstitial defects and defect dusters induced by Fe-ion irradiation are observed in ali the specimens under different conditions. It is found that with increasing irradiation temperature, size of defect clusters increases while the density drops quickly. The results of element chemical mapping from the STEM images indicate that the Si element enrichment and Ta element depletion occur inside the precipitates in the matrix of SIMP steel irradiated to a dose of 1 dpa at 300℃. Correlations between the microstructure and irradiation conditions are briefly discussed.
