The heterogeneous precipitation in the 2:17-type Sm-Co-Fe-Cu-Zr permanent magnets has been found to contain complex formation and dissociation of defects.Though low-temperature pre-aging has been utilized to promote the precipitate nucleation by the enlarged chemical driving force,how the defects evolve after pre-aging and how the possibly changed defects state affects the subsequent precipitation behavior remain unclear.In this work,a model magnet Sm25Co47.9Fe18.5Cu5.6Zr3.0(wt％)was selected to study.Through comparison with the as-solution-treated state,it is found that pre-aging for 2 h at 550℃reduces the defects density,which was characterized by less cell boundaries(i.e.,larger cell size)and less basal stacking faults inside the cells(i.e.,higher 2:17R ordering degree).Further studies reveal that after aging for the same time(10 h)at the same temperature(830℃),the reduced density of defects by pre-aging also leads to slower precipitation/phase transformation kinetics when compared with the non-pre-aged one,which was characterized by the lower 2:17R ordering degree and smaller coercivity for the former.These findings suggest that pre-aging has a strong influence on the density of defects and their evolution during subsequent isothermal aging process,which should be carefully considered to tailor the microstructure and magnetic properties of Sm-Co-Fe-Cu-Zr magnets.

Munzali Musa;Xin Song;Yao Liu;Fang Wang;Jiuping Fan;Tianyu Ma;Xiaobing Ren

Frontier Institute of Science and Technology,State Key Laboratory for Mechanical Behavior of Materials,MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter,Xi'an Jiaotong University,Xi'an 710049,China;Nigeria Police Academy,Faculty of Science,Department of Physics,P.O.Box 14830,Kano State,Nigeria;Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education,Shanxi Normal University,Linfen 041004,China;National Institute for Materials Science,Tsukuba,Ibaraki,305-0047,Japan

稀土学报（英文版）

[1]Munzali Musa;Xin Song;Yao Liu;Fang Wang;Jiuping Fan;Tianyu Ma;Xiaobing Ren-.Effects of pre-aging on defects evolution and magnetic properties of Sm-Co-Fe-Cu-Zr magnets)[J].稀土学报（英文版）,2022(12):1878-1884

Sm25Co47,9Fe18,5Cu5,6Zr3

Effects,aging,defects,evolution,magnetic,properties,magnets,heterogeneous,precipitation,type,permanent,been,found,contain,complex,dissociation,Though,temperature,utilized,promote,precipitate,nucleation,by,enlarged,chemical,driving,force,how,evolve,after,possibly,changed,state,affects,subsequent,behavior,remain,unclear,In,this,work,model,wt,was,selected,study,Through,comparison,solution,treated,that,reduces,density,which,characterized,less,boundaries,larger,size,basal,stacking,faults,inside,cells,higher,17R,ordering,degree,Further,studies,reveal,same,reduced,also,leads,slower,phase,transformation,kinetics,when,compared,aged,one,smaller,coercivity,former,These,findings,suggest,strong,influence,their,during,isothermal,process,should,carefully,considered,tailor,microstructure

0.494509