Recently,a novel 718 superalloy with remarkable structural stability at 680℃has been designed and fabricated by CISRI(Central Iron and Steel Research Institute)etc.Phase identification of novel 718 alloy under the ab...Recently,a novel 718 superalloy with remarkable structural stability at 680℃has been designed and fabricated by CISRI(Central Iron and Steel Research Institute)etc.Phase identification of novel 718 alloy under the above-mentioned heat-treatment condition was performed using optical microscopy(OM),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).Results show that the novel 718 alloy has outstanding structural stability at 680℃.The novel 718alloy possess excellent structural stability and good mechanical properties,which is attributed to y-phase strengthening and also to the specific sandwich structure of theγ′+γ'strengthening phase.展开更多
Co2FeAl nanoparticles were synthesized by reducing the coprecipitated precursor of COCl2·6H2O, Fe（NO3）3·9H2O and AI2（SO4）3·18H2O under H2 atmosphere with various annealing temperatures and durations...Co2FeAl nanoparticles were synthesized by reducing the coprecipitated precursor of COCl2·6H2O, Fe（NO3）3·9H2O and AI2（SO4）3·18H2O under H2 atmosphere with various annealing temperatures and durations. X-ray diffraction and transmission electron microscopy were used to characterize the crystal structure and microstructure of Co2FeAl particles, respectively. The investigation indicates that the crystal structure of CO2FeAI particles tends to be B2 structure, in which atoms are partially ordered. The saturation magnetization and hyperfine field of CO2FeAI particles, which were measured under a vibrating sample magnetometer and a 57Fe Mossbauer spectroscope, are consistent with those of the bulk sample and thin films. Furthermore, the higher annealing temperature and the longer annealing time, the better crystallinity of CO2FeAI and more ordered arrangement of atoms will be. It turned out that the coprecipitation thermal deoxidization method could be an easy and high efficient way to obtain the half-metallic CO2FeAI nanoparticles.展开更多
基金This work was supported by the National High Technical Reasearch and Development Programme of China(No.2002AA305208)China Postdoctoral Science Foundation(No.2005037323).
文摘Recently,a novel 718 superalloy with remarkable structural stability at 680℃has been designed and fabricated by CISRI(Central Iron and Steel Research Institute)etc.Phase identification of novel 718 alloy under the above-mentioned heat-treatment condition was performed using optical microscopy(OM),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).Results show that the novel 718 alloy has outstanding structural stability at 680℃.The novel 718alloy possess excellent structural stability and good mechanical properties,which is attributed to y-phase strengthening and also to the specific sandwich structure of theγ′+γ'strengthening phase.
基金supported by the National Natural Science Foundation of China(Nos.51171076,51101079)
文摘Co2FeAl nanoparticles were synthesized by reducing the coprecipitated precursor of COCl2·6H2O, Fe（NO3）3·9H2O and AI2（SO4）3·18H2O under H2 atmosphere with various annealing temperatures and durations. X-ray diffraction and transmission electron microscopy were used to characterize the crystal structure and microstructure of Co2FeAl particles, respectively. The investigation indicates that the crystal structure of CO2FeAI particles tends to be B2 structure, in which atoms are partially ordered. The saturation magnetization and hyperfine field of CO2FeAI particles, which were measured under a vibrating sample magnetometer and a 57Fe Mossbauer spectroscope, are consistent with those of the bulk sample and thin films. Furthermore, the higher annealing temperature and the longer annealing time, the better crystallinity of CO2FeAI and more ordered arrangement of atoms will be. It turned out that the coprecipitation thermal deoxidization method could be an easy and high efficient way to obtain the half-metallic CO2FeAI nanoparticles.
