The recrystallization and texture evolution of cold-rolled FeCrAl-0.65 Nb and FeCrAl-1.2 Nb alloys thin-wall tubes annealed at 600−900℃ for 1−600 min were investigated.The microstructures were characterized by electr...The recrystallization and texture evolution of cold-rolled FeCrAl-0.65 Nb and FeCrAl-1.2 Nb alloys thin-wall tubes annealed at 600−900℃ for 1−600 min were investigated.The microstructures were characterized by electron back scattering diffraction,electron probe micro-analyzer and transmission electron microscopy.The Vickers hardness and room temperature tensile properties were tested.The results showed that the hardness of fully recrystallized FeCrAl-1.2 Nb alloy was higher and more likely to recrystallize than FeCrAl-0.65 Nb alloy.The weak texture strength of annealing sample was obtained and the proportion of<111>//ND texture increased.The fine Laves phase distributed uniformly in FeCrAl-0.65 Nb alloy had good pinning effect and inhibited recrystallization.Higher Nb content had little effects on tensile properties of thin-wall tube,and induced the formation of larger Laves phase.There was less fine Laves phase pinning in the large area adjacent to the blocky Laves phase,which resulted in easy recrystallization in FeCrAl-1.2 Nb alloy.展开更多
The microstructures and interracial characteristics of matrices at the inwalls and the out-walls of the cold-rolled tube with different amounts of deformation were investigated by the scanning electronic microscope （...The microstructures and interracial characteristics of matrices at the inwalls and the out-walls of the cold-rolled tube with different amounts of deformation were investigated by the scanning electronic microscope （SEM）, the optical microscope （OM）, and the transmission electronic microscope （TEM） techniques. It was observed that as the amount of deformation increases, the flaws nucleate at the out-walls of the cold rolled tube, the stress-induced martensites change from （111 ） type Ⅰ twins to （011） type Ⅱ twins and then to （100） compound twins, nanocrystals and bulk amorphisation happen, the high density dislocation causes stress concentration at the out-walls of the Ti50Ni50 cold-rolled tube, and then precipitates its fracture, and the Ti2Ni particles strengthen the grain boundaries and curb the dislocation movements during plastic deformation. The inhomogeneity level of the grains in the Ti50Ni50 alloy plays an important role on the fracture of the Ti50Ni50 cold rolled tube.展开更多
For uniform tube inner coating of non-conductive thin films, the double-ended coaxial magnetron pulsed plasma (DCMPP) method was investigated. In this study, coating of TiN and TiO2 was performed. It was clearly shown...For uniform tube inner coating of non-conductive thin films, the double-ended coaxial magnetron pulsed plasma (DCMPP) method was investigated. In this study, coating of TiN and TiO2 was performed. It was clearly shown that the extended anode effect was strongly influenced by the electric resistance of the coated thin films on the inner surface of an insulator tube. Additionally, high frequency (100 kHz) was better for relatively high plasma density. On the other hand, in the case of titanium oxide deposition, negative ion productions drastically decrease the deposition rate and the shifting velocity of plasma main position for coated TiO2 films.展开更多
Neutron tube is a kind of accelerator neutron source, which has been applied extensively. It is mainly composed of an ion source system, an accelerator system, and a target system. The target system is one of the most...Neutron tube is a kind of accelerator neutron source, which has been applied extensively. It is mainly composed of an ion source system, an accelerator system, and a target system. The target system is one of the most important parameters of the neutron tube and it impacts directly the yield, the lifetime, and the stability. By far the relation between the property of neutron tube and target thickness has not been studied drastically in the Institute of Radiation Technology of Northeast Normal University. High-quality titanium target should be produced in order to manufacture the neutron tube with intense yield, long lifetime and high stability. In our experiment, the pure titanium film was evaporated on the ceramic target by using the evaporation technique. The impact of the thickness of the titanium film on the yield of the neutron tube was studied, and the yield of the neutron tube was on optimistic state if the thickness of titanium film was 2.2 μm. The properties of training and stability of neutron tubes with different thick titanium film target were also present in this paper.展开更多
基金Project(2019YFB1901002)supported by the Key Project of Nuclear Safety and Advanced Nuclear Technology,ChinaProject supported by State Key Laboratory of Powder Metallurgy,China。
文摘The recrystallization and texture evolution of cold-rolled FeCrAl-0.65 Nb and FeCrAl-1.2 Nb alloys thin-wall tubes annealed at 600−900℃ for 1−600 min were investigated.The microstructures were characterized by electron back scattering diffraction,electron probe micro-analyzer and transmission electron microscopy.The Vickers hardness and room temperature tensile properties were tested.The results showed that the hardness of fully recrystallized FeCrAl-1.2 Nb alloy was higher and more likely to recrystallize than FeCrAl-0.65 Nb alloy.The weak texture strength of annealing sample was obtained and the proportion of<111>//ND texture increased.The fine Laves phase distributed uniformly in FeCrAl-0.65 Nb alloy had good pinning effect and inhibited recrystallization.Higher Nb content had little effects on tensile properties of thin-wall tube,and induced the formation of larger Laves phase.There was less fine Laves phase pinning in the large area adjacent to the blocky Laves phase,which resulted in easy recrystallization in FeCrAl-1.2 Nb alloy.
文摘The microstructures and interracial characteristics of matrices at the inwalls and the out-walls of the cold-rolled tube with different amounts of deformation were investigated by the scanning electronic microscope （SEM）, the optical microscope （OM）, and the transmission electronic microscope （TEM） techniques. It was observed that as the amount of deformation increases, the flaws nucleate at the out-walls of the cold rolled tube, the stress-induced martensites change from （111 ） type Ⅰ twins to （011） type Ⅱ twins and then to （100） compound twins, nanocrystals and bulk amorphisation happen, the high density dislocation causes stress concentration at the out-walls of the Ti50Ni50 cold-rolled tube, and then precipitates its fracture, and the Ti2Ni particles strengthen the grain boundaries and curb the dislocation movements during plastic deformation. The inhomogeneity level of the grains in the Ti50Ni50 alloy plays an important role on the fracture of the Ti50Ni50 cold rolled tube.
文摘For uniform tube inner coating of non-conductive thin films, the double-ended coaxial magnetron pulsed plasma (DCMPP) method was investigated. In this study, coating of TiN and TiO2 was performed. It was clearly shown that the extended anode effect was strongly influenced by the electric resistance of the coated thin films on the inner surface of an insulator tube. Additionally, high frequency (100 kHz) was better for relatively high plasma density. On the other hand, in the case of titanium oxide deposition, negative ion productions drastically decrease the deposition rate and the shifting velocity of plasma main position for coated TiO2 films.
文摘Neutron tube is a kind of accelerator neutron source, which has been applied extensively. It is mainly composed of an ion source system, an accelerator system, and a target system. The target system is one of the most important parameters of the neutron tube and it impacts directly the yield, the lifetime, and the stability. By far the relation between the property of neutron tube and target thickness has not been studied drastically in the Institute of Radiation Technology of Northeast Normal University. High-quality titanium target should be produced in order to manufacture the neutron tube with intense yield, long lifetime and high stability. In our experiment, the pure titanium film was evaporated on the ceramic target by using the evaporation technique. The impact of the thickness of the titanium film on the yield of the neutron tube was studied, and the yield of the neutron tube was on optimistic state if the thickness of titanium film was 2.2 μm. The properties of training and stability of neutron tubes with different thick titanium film target were also present in this paper.
