The solid state interdiffusion between NiFe204 and NiO in nitrogen atmosphere was studied by means of diffusion couple technique. NiFe204/NiO diffusion couple with plane interfaces was made by clamping method and sint...The solid state interdiffusion between NiFe204 and NiO in nitrogen atmosphere was studied by means of diffusion couple technique. NiFe204/NiO diffusion couple with plane interfaces was made by clamping method and sintering at 1 300℃ for 10 h. Scanning electronic microscopy （SEM） and energy-dispersive X-ray spectrometry （EDS） were used to analyze the microstructure and phase composition of the diffusion couples. The results indicate that a porous layer of uniform thickness forms along the NiFe2O4/NiO bonding interface and exhibits a deep penetration in the NiFe2O4 due to the Kirkendall effect. Furthermore, SEM observations reveal that the needle-like nickel ferrite precipitates form in NiO near the interface and the formation mechanism of them are inferred to be diffusion type solid-state phase changes.展开更多
基金Project(50721003) supported by the National Natural Science Fund for Innovation Group of ChinaProject(2008AA030501) supported by the National High Technology Research and Development Program of China
文摘The solid state interdiffusion between NiFe204 and NiO in nitrogen atmosphere was studied by means of diffusion couple technique. NiFe204/NiO diffusion couple with plane interfaces was made by clamping method and sintering at 1 300℃ for 10 h. Scanning electronic microscopy （SEM） and energy-dispersive X-ray spectrometry （EDS） were used to analyze the microstructure and phase composition of the diffusion couples. The results indicate that a porous layer of uniform thickness forms along the NiFe2O4/NiO bonding interface and exhibits a deep penetration in the NiFe2O4 due to the Kirkendall effect. Furthermore, SEM observations reveal that the needle-like nickel ferrite precipitates form in NiO near the interface and the formation mechanism of them are inferred to be diffusion type solid-state phase changes.
