Cu、Ga和C掺杂对MnAl合金相结构及磁性能的影响

研究Cu、Ga、C元素掺杂的MnAl合金的相结构和磁性能。结果表明:在Cu或者Ga掺杂的MnAl合金中加入C元素,有助于磁性相τ-MnAl的形成。Mn_(50)Al_(47)Ga_3C_3粉末的饱和磁化强度(M_s)随着球磨时间的增加而减小,矫顽力(H_c)随着球磨时间的增加先增大后减小。球磨前Mn_(50)Al_(47)Ga_3C_3合金(1000℃×20 h)样品的饱和磁化强度为89.98 Am~2/kg,约为其理论饱和磁化强度值144 Am~2/kg的62.5%;获得最好磁性能是在粉末球磨1h后,Ms=51.91Am~2/kg,Hc=155.2 kA/m。     

Fe_3O_4磁性纳米颗粒的制备及性能表征

以Fe_2(SO_4)_3·6H_2O,FeSO_4·4H_2O和NH_3·H_2O为原料,采用化学共沉淀法制备Fe_3O_4磁性纳米颗粒,并通过XRD、FTIR、TEM和VSM手段,研究了反应温度对其结构、形貌和磁性能的影响。结果表明:制备的Fe_3O_4磁性纳米颗粒表面包裹了一层有机物质,呈球形,大小均匀,平均粒径在13nm左右,分散性好,饱和磁化强度Ms最大值可达53.38A·m~2·kg~(–1),且反应温度70℃时其磁性能最佳。     

Sn、Si和C掺杂对MnAl合金相结构及磁性能的影响

研究了 Sn、Si和C元素掺杂对低Mn含量MnAl合金的相结构和磁性能的影响.结果表明:Sn元素的掺杂比Si元素的掺杂更容易稳定磁性τ相.C、Sn和C、Si双元素均比单元素掺杂有利于稳定磁性相.随着Mn含量的增加,1100℃热处理后,MnAl合金相结构中出现少量高温ε相,后续再进行500℃热处理,ε相转变成磁性τ相.在...     

Phase relationships in the Yb-Fe-Sb system at 530℃

Phase relationships in the Yb-Fe-Sb ternary system at 530℃ were investigated mainly by powder metallurgy and X-ray powder diffraction. Nine binary compounds (Yb6Fe23, Yb2Fe17, FeSb, FeSb2, YbSb2, YbSb, Yb11Sb10, Yb4Sb3, and αYb5Sb3) and one ternary compound (Fe4YbSb12) were confirmed in this system at 530℃. The homogeneity range of FeSb phase extended from approximately 43at.%Sb to 45at.%Sb, the maximum solid solubility of Sb in Fe phase and Yb in FeSb phase was approximately 3at.%Sb and 1at.%Yb at 530℃, respectively. Isothermal section of the phase diagram of the Yb-Fe-Sb ternary system at 530℃ consisted of thirteen single-phase regions, twenty-four two-phase regions, and twelve three-phase regions.