The growing demand for high-efficiency and low-loss energy conversion and transportation techniques urges the development of advanced Fe-Si based soft magnet alloys.Simultaneous achievement of low coercivity(Hc)and la...The growing demand for high-efficiency and low-loss energy conversion and transportation techniques urges the development of advanced Fe-Si based soft magnet alloys.Simultaneous achievement of low coercivity(Hc)and large saturation magnetization(Ms)however,remains challenging.In this study,soft magnetic alloys with the composition Fe82-xSi18Cox(x=0 at.%,4 at.%,8 at.%,12 at.%,16 at.%,and 20 at.%)have been designed followed by microstructural tuning.The Co incorporation results in initially decreased Hc followed by increment due to reduced magnetocrystalline anisotropy and increased saturation mag-netostriction from negative to positive values of the alloys.Meanwhile,the Ms raises with subsequent reduction,which origins from competitive mechanisms of increased average moment of Fe atoms and decreased average moment of Co atoms according to first principles calculations.Microstructural evolu-tion during annealing of the Fe70Si18C012 with synergistically optimized Hc and Ms has been revealed that after elevated-temperature annealing,the DO3 phase is predominately transformed from the B2 phase ac-companied by an increase in the degree of ordering.The growth of the DO3 phase deteriorates the Hc due to the aggravating pinning effect on the domain wall movement,which arises from the inhomogeneous magnetization distribution caused by increasing antiphase boundaries.展开更多
本文研究了添加微量元素Si对HDDR工艺制备各向异性Nd Fe Co B Si系永磁磁粉的磁性能和磁粉结构的影响。研究结果表明 :添加Si可以显著地提高磁粉的矫顽力和各向异性 ,Si的添加可以细化晶粒 ,还能使反磁化畴难以形核 ,因而磁粉的矫顽力...本文研究了添加微量元素Si对HDDR工艺制备各向异性Nd Fe Co B Si系永磁磁粉的磁性能和磁粉结构的影响。研究结果表明 :添加Si可以显著地提高磁粉的矫顽力和各向异性 ,Si的添加可以细化晶粒 ,还能使反磁化畴难以形核 ,因而磁粉的矫顽力较高。目前对于添加Si的Nd Fe展开更多
基金supported by the National Key R&D Program of China(No.2021YFB3501303)the National Natural Science Foundation of China(No.52122106)+3 种基金the"Pioneer"R&D Program of Zhejiang Province(No.2022C01230)"Leading Goose"R&D Program of Zhejiang Province(No.2022C01110)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2021SZ-FR005)the Space Application System of China Manned Space Program(No.KJZ-YY-NCL03).
文摘The growing demand for high-efficiency and low-loss energy conversion and transportation techniques urges the development of advanced Fe-Si based soft magnet alloys.Simultaneous achievement of low coercivity(Hc)and large saturation magnetization(Ms)however,remains challenging.In this study,soft magnetic alloys with the composition Fe82-xSi18Cox(x=0 at.%,4 at.%,8 at.%,12 at.%,16 at.%,and 20 at.%)have been designed followed by microstructural tuning.The Co incorporation results in initially decreased Hc followed by increment due to reduced magnetocrystalline anisotropy and increased saturation mag-netostriction from negative to positive values of the alloys.Meanwhile,the Ms raises with subsequent reduction,which origins from competitive mechanisms of increased average moment of Fe atoms and decreased average moment of Co atoms according to first principles calculations.Microstructural evolu-tion during annealing of the Fe70Si18C012 with synergistically optimized Hc and Ms has been revealed that after elevated-temperature annealing,the DO3 phase is predominately transformed from the B2 phase ac-companied by an increase in the degree of ordering.The growth of the DO3 phase deteriorates the Hc due to the aggravating pinning effect on the domain wall movement,which arises from the inhomogeneous magnetization distribution caused by increasing antiphase boundaries.
