To fully release the potential of wide bandgap(WBG)semiconductors and achieve high energy density and efficiency,a carbonyl iron soft magnetic composite(SMC)with an easy plane-like structure is prepared.Due to this st...To fully release the potential of wide bandgap(WBG)semiconductors and achieve high energy density and efficiency,a carbonyl iron soft magnetic composite(SMC)with an easy plane-like structure is prepared.Due to this structure,the permeability of the composite increases by 3 times(from 7.5 to 21.5)at 100 MHz compared with to the spherical carbonyl iron SMC,and the permeability changes little at frequencies below 100 MHz.In addition,the natural resonance frequency of the composite shifts to higher frequencies at 1.7 GHz.The total core losses of the composites at 10,20,and 30 m T are80.0,355.3,and 810.7 m W/cm^(3),respectively,at 500 k Hz.Compared with the spherical carbonyl iron SMC,the core loss at500 k Hz is reduced by more than 60%.Therefore,this kind of soft magnetic composite with an easy plane-like structure is a good candidate for unlocking the potential of WBG semiconductors and developing the next-generation power electronics.展开更多
The high-performance electromagnetic(EM)wave absorption material Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)was prepared by solid-state reaction,and its EM wave absorption properties were deeply studied.The results reveale...The high-performance electromagnetic(EM)wave absorption material Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)was prepared by solid-state reaction,and its EM wave absorption properties were deeply studied.The results revealed that Ba(Co Ti)x Fe12-2x O19@Bi Fe O_(3)could obtain excellent absorption properties in hundreds of megahertz by adjusting the Co^(2+)-Ti^(4+)content.The best comprehensive property was obtained for x=1.2,where the optimal reflection loss(RL)value reaches-30.42 d B at about 600 MHz with thickness of 3.5 mm,and the corresponding effective absorption band covers the frequency range of 437 MHz-1 GHz.Moreover,the EM wave absorption mechanism was studied based on the simulation methods.The simulated results showed that the excellent EM wave absorption properties of Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)mainly originated from the internal loss caused by natural resonance,and the interface cancelation further improved the absorption properties and resulted in RL peaks.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11574122 and 51731001)Joint Fund of Equipment Pre-Research and Ministry of Education,China(Grant No.6141A02033242)。
文摘To fully release the potential of wide bandgap(WBG)semiconductors and achieve high energy density and efficiency,a carbonyl iron soft magnetic composite(SMC)with an easy plane-like structure is prepared.Due to this structure,the permeability of the composite increases by 3 times(from 7.5 to 21.5)at 100 MHz compared with to the spherical carbonyl iron SMC,and the permeability changes little at frequencies below 100 MHz.In addition,the natural resonance frequency of the composite shifts to higher frequencies at 1.7 GHz.The total core losses of the composites at 10,20,and 30 m T are80.0,355.3,and 810.7 m W/cm^(3),respectively,at 500 k Hz.Compared with the spherical carbonyl iron SMC,the core loss at500 k Hz is reduced by more than 60%.Therefore,this kind of soft magnetic composite with an easy plane-like structure is a good candidate for unlocking the potential of WBG semiconductors and developing the next-generation power electronics.
基金Project supported by the National Natural Science Foundation of China(Grant No.11574122)the Joint Fund of Equipment Pre-Research and Ministry of Education,China(Grant No.6141A02033242)。
文摘The high-performance electromagnetic(EM)wave absorption material Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)was prepared by solid-state reaction,and its EM wave absorption properties were deeply studied.The results revealed that Ba(Co Ti)x Fe12-2x O19@Bi Fe O_(3)could obtain excellent absorption properties in hundreds of megahertz by adjusting the Co^(2+)-Ti^(4+)content.The best comprehensive property was obtained for x=1.2,where the optimal reflection loss(RL)value reaches-30.42 d B at about 600 MHz with thickness of 3.5 mm,and the corresponding effective absorption band covers the frequency range of 437 MHz-1 GHz.Moreover,the EM wave absorption mechanism was studied based on the simulation methods.The simulated results showed that the excellent EM wave absorption properties of Ba(Co Ti)_(x)Fe_(12-2x)O19@Bi Fe O_(3)mainly originated from the internal loss caused by natural resonance,and the interface cancelation further improved the absorption properties and resulted in RL peaks.