Synthesis of magnetically exchange coupled SrFe12O19/FeCo composites through cryogenic ball milling

SrFe12O19/FeCo composite particles with different mass ratios of SrFe12O19 to FeCo were synthesized through a cryogenic ball milling process. The corresponding products were characterized with scanning electron microscopy (SED), transmission electron microscopy (TEM), x-ray diffraction (XRD) and vibrating sample magnetometer (VSM) for crystal morphology, elemental distribution, crystal phases, and magnetic properties. The results showed that when the mass percentage of FeCo was less than 15%, smooth magnetic hysteresis loops could be obtained from SrFe12O19/FeCo composite particles, indicating effective magnetic exchange coupling between the SrFe12O19 and FeCo particles. A further FeCo mass increase resulted in kinks in the magnetic hysteresis loop and destroyed the magnetic exchange coupling. As a comparison, room temperature ball milling of SrFe12O19/FeCo (95/5 wt%) cannot achieve magnetic exchange coupling between SrFe12O19 and FeCo due to FeCo nanoparticle agglomeration.

[1]  George S. Dulikravich,et al.  Magnetic Alloys Design Using Multi-objective Optimization , 2017 .

[2]  Shuchun Hu,et al.  Synthesis of mono-dispersed Fe-Co nanoparticles with precise composition control , 2017 .

[3]  George S. Dulikravich,et al.  On the evolution of Cu-Ni-rich bridges of Alnico alloys with tempering , 2016 .

[4]  C. Poloni,et al.  Algorithms for design optimization of chemistry of hard magnetic alloys using experimental data , 2016 .

[5]  C. Koch,et al.  Structure and magnetic properties of a multi-principal element Ni–Fe–Cr–Co–Zn–Mn alloy , 2016 .

[6]  Yan Zhang,et al.  Artificially produced rare-earth free cosmic magnet , 2015, Scientific Reports.

[7]  J. Cui,et al.  Magnetic self-assembly for the synthesis of magnetically exchange coupled MnBi/Fe–Co composites , 2015 .

[8]  Jeffrey E. Shield,et al.  Phase transformation and magnetic properties of rapidly solidified Mn-Al-C alloys modified with Zr , 2015 .

[9]  K. Lynn,et al.  Defect generation and analysis in mechanically alloyed stoichiometric Fe-Ni alloys , 2015 .

[10]  P. Mukherjee,et al.  High-energy mechanical milling-induced crystallization in Fe32Ni52Zr3B13 , 2014 .

[11]  R. Ramanujan,et al.  Enhancing the coercivity, thermal stability and exchange coupling of nano-composite (Nd,Dy,Y)–Fe–B alloys with reduced Dy content by Zr addition , 2014 .

[12]  Qingfang Liu,et al.  Improved magnetic properties of SrFe12O19/FeCo core–shell nanofibers by hard/soft magnetic exchange–coupling effect , 2014 .

[13]  Shouheng Sun,et al.  Building nanocomposite magnets by coating a hard magnetic core with a soft magnetic shell. , 2014, Angewandte Chemie.

[14]  N. Poudyal,et al.  Hard-phase engineering in hard/soft nanocomposite magnets , 2014 .

[15]  J. Liu,et al.  Synthesis of monodisperse FeCo nanoparticles by reductive salt-matrix annealing , 2013, Nanotechnology.

[16]  T. Jin,et al.  Phase relationship of the TbO1.81–Mn3O4–Fe2O3 system synthesized at 1200 °C , 2013 .

[17]  D. Sellmyer,et al.  Assembly of uniaxially aligned rare-earth-free nanomagnets , 2012 .

[18]  J. Liu,et al.  Exchange-coupled nanoscale SmCo/NdFeB hybrid magnets , 2012 .

[19]  J. Liu,et al.  Effect of pressure loading rate on the crystallographic texture of NdFeB nanocrystalline magnets , 2012 .

[20]  J. Liu,et al.  Bulk SmCo5/α-Fe nanocomposite permanent magnets fabricated by mould-free Joule-heating compaction , 2011 .

[21]  L. Zhen,et al.  Magnetic microstructures of a high coercivity Nd–Fe–B sintered magnet in remanent and incomplete thermal demagnetization states , 2010 .

[22]  J. Liu,et al.  Bimagnetic nanoparticles with enhanced exchange coupling and energy products , 2009 .

[23]  L. Tagirov,et al.  Dose dependence of ferromagnetism in Co-implanted ZnO , 2008, 0807.4711.

[24]  Jong In Lee,et al.  Exchange coupled magnetic nanocomposites of Sm(Co1−xFex)5 / Fe3O4 with core/shell structure , 2007 .

[25]  J. Schoenung,et al.  Processing and behavior of nanostructured metallic alloys and composites by cryomilling , 2007 .

[26]  Du You-wei,et al.  Ferromagnetic/antiferromagnetic exchange coupling in melt-spun NdFeB nanocomposites , 2006 .

[27]  E. Lavernia,et al.  Nanostructures and deformation mechanisms in a cryogenically ball-milled Al-Mg alloy , 2003 .

[28]  P. G. Bercoff,et al.  High-energy ball milling of Ba-hexaferrite/Fe magnetic composite , 1998 .

[29]  F. Missell,et al.  Chemical composition and coercivity of SmCo5 magnets , 1998 .

[30]  R. Skomski.  Aligned two-phase magnets: Permanent magnetism of the future? , 1994 .

[31]  J. Coey,et al.  Exchange coupling and energy product in random two-phase aligned magnets , 1994 .

[32]  J. Coey,et al.  Giant energy product in nanostructured two-phase magnets. , 1993, Physical review. B, Condensed matter.