Behavior of the coercivity of the high-temperature Sm(Co0.88-xFexCu0.09Zr0.03)7 magnets depending on the temperature and time of annealing with the temperature decreasing stepwise from 700 to 400℃ was investigated.It...Behavior of the coercivity of the high-temperature Sm(Co0.88-xFexCu0.09Zr0.03)7 magnets depending on the temperature and time of annealing with the temperature decreasing stepwise from 700 to 400℃ was investigated.It is shown that the growth rate of coercivity abruptly increases at the initial stage of annealing in the vicinity of the Curie temperature of the SmCo5 phase.The origin of the effect is the counter diffusion of Cu and Co atoms through dislocation tubes,which form because of enhanced stresses and a partial breakage of coherent coupling at the interface of the Sm2 Co17 and SmCo5 phases.Diffusive enrichment of the SmCo5 phase in Cu close to the interface with Sm2 Co17 leads to relaxation of stresses and increases in the gradient of the magnetic domain-wall energy and coercivity.展开更多
The structure and magnetic hysteresis properties of the cast Sm1-xZrx(Fe0.92Ti0.08)10(x = 0-0.3)alloys and melt-spun ribbons prepared from them were studied.In the cast alloy with x>0.2, a considerable amount of th...The structure and magnetic hysteresis properties of the cast Sm1-xZrx(Fe0.92Ti0.08)10(x = 0-0.3)alloys and melt-spun ribbons prepared from them were studied.In the cast alloy with x>0.2, a considerable amount of the eutectic phase is found in the SEM micrographs.Analysis of the temperature dependences of the magnetic susceptibility and XRD patterns allows amorphous state in the as-spun ribbons with x>0.2 to be determined.The specific magnetization measured in a field of 17 kOe and remanence decrease with increasing annealing temperature from 800 to 900 ℃ and weakly depend on Zr concentration.The maximal value of coercivity Hc = 4.7 kOe is obtained on the ribbons with x = 0.2 after annealing at 850℃ for 10 min.After additional hydrogenation of the ribbons,both the coercivity and remanence increase by 54% and 7%,respectively.展开更多
基金Project supported by BRICSSTI Framework Program for Basic Research(RFBR-BRICS)(17-52-80072)DST-BRICS,and the State Assignment of Ministry of Science and Education of Russia(topic “Magnet)(AAAA-A18-118020290129-5)
文摘Behavior of the coercivity of the high-temperature Sm(Co0.88-xFexCu0.09Zr0.03)7 magnets depending on the temperature and time of annealing with the temperature decreasing stepwise from 700 to 400℃ was investigated.It is shown that the growth rate of coercivity abruptly increases at the initial stage of annealing in the vicinity of the Curie temperature of the SmCo5 phase.The origin of the effect is the counter diffusion of Cu and Co atoms through dislocation tubes,which form because of enhanced stresses and a partial breakage of coherent coupling at the interface of the Sm2 Co17 and SmCo5 phases.Diffusive enrichment of the SmCo5 phase in Cu close to the interface with Sm2 Co17 leads to relaxation of stresses and increases in the gradient of the magnetic domain-wall energy and coercivity.
基金Project supported by BRICS STI Framework Program for Basic Research(RFFI-BRICS)(17-52-80072),NSFC-BRICS(51761145026)the State Assignment of Ministry of Education and Science of the Russian Federation(topic “Magnet”)(AAAA-A18-118020290129-5)
文摘The structure and magnetic hysteresis properties of the cast Sm1-xZrx(Fe0.92Ti0.08)10(x = 0-0.3)alloys and melt-spun ribbons prepared from them were studied.In the cast alloy with x>0.2, a considerable amount of the eutectic phase is found in the SEM micrographs.Analysis of the temperature dependences of the magnetic susceptibility and XRD patterns allows amorphous state in the as-spun ribbons with x>0.2 to be determined.The specific magnetization measured in a field of 17 kOe and remanence decrease with increasing annealing temperature from 800 to 900 ℃ and weakly depend on Zr concentration.The maximal value of coercivity Hc = 4.7 kOe is obtained on the ribbons with x = 0.2 after annealing at 850℃ for 10 min.After additional hydrogenation of the ribbons,both the coercivity and remanence increase by 54% and 7%,respectively.
