尼龙6粘结锶铁氧体永磁材料的制备与性能

Preparation and properties of nylon-6 bonded strontium ferrite permanent magnets

以尼龙6和锶铁氧体磁粉为原料,采用热压成型工艺,制备各向同性粘结锶铁氧体永磁体。主要研究了原料的混合方式、磁粉的改性状态以及含量对材料磁性能(剩余磁通密度Br,内禀矫顽力Hcj,最大磁能积(BH)max)和力学性能(耐压强度Rc)的影响。结果表明,挤出造粒可以有效改善磁粉在尼龙6中的分散性,硅烷偶联剂的加入显著提高了磁体的力学性能。当未改性磁粉含量为90 wt%时,磁体具有良好的磁性能:Br=159 mT,Hcj=236 kA/m,(BH)_(max)=4.5 kJ/m^3,改性磁粉含量为85 wt%时,磁体的力学性能最佳(R_c=52.1 MPa)。

Isotropic strontium ferrite bonded permanent magnets were prepared via hot-press technique using nylon-6and strontium ferrite magnet powder as raw materials.The effects of mixing methods and the magnet powder concentration on the magnetic and mechanical properties of the product,i.e.residual magnetic flux density(Br),intrinsic coercive force(Hcj),maximum energy product(BH)max and compressive strength(Rc)were investigated.The results show that extrusion granulation can improve the dispersibility of magnetic particles in nylon-6matrix effectively.The addition of saline coupling agent significantly enhances the mechanical properties.For bonded magnets with about90%mass fraction of unmodified strontium ferrite powder,products exhibit good magnetic properties of Br(159mT),Hcj(236kA/m)and(BH)max(4.5kJ/m3),meanwhile,with about85%mass fraction of modified magnet powder,products show excellent mechanical property of Rc(52.1MPa).