热处理对(Fe_(0.52)Co_(0.30)Ni_(0.18))_(73)Cr_(17)Zr_(10)非晶合金的组织结构及磁性能的影响

采用单辊急冷法制备(Fe_(0.52)Co_(0.30)Ni_(0.18))_(73)Cr_(17)Zr_(10)非晶薄带,并对该合金进行等温退火。采用XRD,AFM,VSM研究退火温度对(Fe_(0.52)Co_(0.30)Ni_(0.18))_(73)Cr_(17)Zr_(10)非晶合金的组织结构和磁性能的影响。结果表明:非晶合金晶化过程为Am→α-Fe(Co)+Am′→α-Fe(Co)+Cr_2Ni_3+Fe_3Ni_2+Cr_2Zr+未知相。当退火温度Ti玻璃转变温度Tg时,由于结构弛豫、内应力的释放,合金的饱和磁化强度Ms有所提高;当晶化起始温度TxTi第一晶化峰值温度Tp1时,由于铁磁性α-Fe(Co)相的析出,Ms显著提升;当TiTp1时,由于晶粒长大和第二相的析出,Ms急剧恶化,565℃退火能够获得最好磁性能(Ms=106.8A·m~2·kg~(-1))。490℃和565℃退火后薄带表面的AFM观察表明,AFM图片所呈现的颗粒尺寸要比用Scherrer法测得的α-Fe(Co)纳米晶尺寸大得多,这是典型的包裹晶粒现象。

Effects of Heat T reatment on M icrostructure and Magnetic Properties of (Fe0 .52Co0 .30Ni0 .18)73Cr17Zr10 Amorphous Alloy

(Fe0.52Co0.30Ni0.18)73Cr17Zr10 amorphous ribbons were prepared by melt‐spun method and an‐nealed at different temperatures . X‐ray diffraction , atomic force microscopy and vibrating sample magnetometer w ere adopted to study the effect of annealing temperature on the microstructure and magnetic properties of this alloy .The results show that the crystallization process of this alloy is amorphous → α‐Fe (Co ) + amorphous′ → α‐Fe (Co ) + Cr2 Ni3 + Fe3 Ni2 + Cr2 Zr + unidentified phase .When annealing temperature Ti is lower than Tg ,the Ms increases slightly as a result of relaxa‐tion of the internal stress of the as‐quenched amorphous alloy .When Ti is in between Tx and Tp1 ,the Ms significantly increases due to the partial crystallization of amorphous precursors to create a homo‐geneous distribution of α‐Fe(Co) nanocrystals within a residual amorphous matrix .When Ti is higher than Tp1 ,the Ms drops rapidly ,w hich may be caused by the grain grow th and the formation of para‐magnetic phase .This alloy after annealed at 565℃ has the best magnetic property (Ms = 106 .8A · m2 · kg -1 ) .The results of AFM observation show that in the annealed amorphous ribbons the grain size measured from AFM graphs is much larger than that of theα‐Fe(Co) nanocrystal size caculated by Scherrer method ,w hich is a typical phenomenon of coated grain .