The σ-phase precipitation in 20% cold-worked 15Cr-15Ni titanium-modified austenitic stainless steel was studied during long-term aging treatment.During the isothermal aging stage,the amount of a-phase was significant...The σ-phase precipitation in 20% cold-worked 15Cr-15Ni titanium-modified austenitic stainless steel was studied during long-term aging treatment.During the isothermal aging stage,the amount of a-phase was significantly increased at beginning and gradually became constant.The aging time only slightly affected the size and morphology of the σ-phase.Conversely,during the isochronal aging stage,the amount ofσ-phase grew rapidly with the increase in the aging temperature.The σ-phase with a large amount of stacking faults was prone to nucleate around the（Ti,Mo）C particles or at the grain boundaries.The（Ti,Mo）C particles can act as effective nucleation sites,where the σ-phase directly precipitates from the austenitic matrix.From this work,the growth of σ-phase is found to be influenced by the aging temperature,and a new mechanism of σ-phase precipitation from austenite has been proposed.展开更多
The swelling behavior of 20% cold-worked 15-15Ti steels with （0.23-0.40） wt% titanium and （0.42-0.81） wt% silicon content after heavy-ion beam irradiation has been investigated by transmission electron microscopy....The swelling behavior of 20% cold-worked 15-15Ti steels with （0.23-0.40） wt% titanium and （0.42-0.81） wt% silicon content after heavy-ion beam irradiation has been investigated by transmission electron microscopy. The results show that 15-15Ti steel with higher titanium content displays lower swelling. As silicon content increases, the cavity size and the swelling of the 15-15Ti steels decrease obviously. Titanium and silicon may play important roles in suppressing the cavity nucleation and growth in 15-15Ti steel.展开更多
文摘The σ-phase precipitation in 20% cold-worked 15Cr-15Ni titanium-modified austenitic stainless steel was studied during long-term aging treatment.During the isothermal aging stage,the amount of a-phase was significantly increased at beginning and gradually became constant.The aging time only slightly affected the size and morphology of the σ-phase.Conversely,during the isochronal aging stage,the amount ofσ-phase grew rapidly with the increase in the aging temperature.The σ-phase with a large amount of stacking faults was prone to nucleate around the（Ti,Mo）C particles or at the grain boundaries.The（Ti,Mo）C particles can act as effective nucleation sites,where the σ-phase directly precipitates from the austenitic matrix.From this work,the growth of σ-phase is found to be influenced by the aging temperature,and a new mechanism of σ-phase precipitation from austenite has been proposed.
基金supported from the National Natural Science Foundation of China(Grant Nos.11005158 and 9112600)the National major project of science and technology(Grant No.2012ZX06004-005-005)
文摘The swelling behavior of 20% cold-worked 15-15Ti steels with （0.23-0.40） wt% titanium and （0.42-0.81） wt% silicon content after heavy-ion beam irradiation has been investigated by transmission electron microscopy. The results show that 15-15Ti steel with higher titanium content displays lower swelling. As silicon content increases, the cavity size and the swelling of the 15-15Ti steels decrease obviously. Titanium and silicon may play important roles in suppressing the cavity nucleation and growth in 15-15Ti steel.
