In this work, the effects of Pr content on the structure and intrinsic magnetic properties of Sml-xPrxCO5 （x = 0-0.6） compounds prepared by induction melting were systematically investigated by scanning electron mic...In this work, the effects of Pr content on the structure and intrinsic magnetic properties of Sml-xPrxCO5 （x = 0-0.6） compounds prepared by induction melting were systematically investigated by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and magnetic measurements. Microstructural observation and chemical composition analysis show that Sml xPrxCos compounds are composed of （Sin, Pr）Co （1：5） phase and （Sm, Pr）-rich grain boundary phase. XRD results show that all the Sml-xPrxCO5 compounds have a （Sm, Pr）lCo main phase with the hexagonal CaCus-type crystal structure and the （Sm, Pr）2 Co7 impurity phase. In addition, the detailed research shows that the lattice constants （a, c） and unit volume （V） are all enlarged with the increases in Pr con- tent. According to the magnetic measurements, as the Pr content increases to larger than 0.4, both the Curie tem- perature （Tc） and the anisotropy field （HA） of all the Pr- doped compounds decrease rapidly. Meanwhile, the mag- netization of Sml_xPr.Co5 compounds at applied field of 14 T （MI4 T） are observably improved with Pr doping content of x 〉 0.3. Among them, Smo.6Pro.4Co5 compound exhibits slightly lower HA and Tc, but much higher M14 T than those of the binary SmCos, indicating that doping of proper Pr content into SmCo5 compound can optimize the intrinsic magnetic properties. As a result, the optimal intrinsic magnetic properties of HA = 29.11 T,Tc = 989 K, and M14 T = 102.31 mA.m2.g-1 are obtained in Smo.6Pro.4C05 compound.展开更多
Structure, magnetic properties, and thermal stability of ternary Sm1-xTmxCo5 compounds were studied via X-ray diffraction（XRD）, thermal magnetic analysis（TMA）, and magnetic measurements. XRD results show that all ...Structure, magnetic properties, and thermal stability of ternary Sm1-xTmxCo5 compounds were studied via X-ray diffraction（XRD）, thermal magnetic analysis（TMA）, and magnetic measurements. XRD results show that all the compounds have a main phase of hexagonal CaCu5-type crystal structure with small amount of impurity phases; increasing Tm content is associated with contraction of the hexagonal unit cell in the direction of the c axis and expansion of the a and b parameters. TMA results indicate that the Curie temperature（TC） of Sm1-xTmxCo5 compounds gets higher with the increase in Tm content.Magnetic measurements show that both the magnetic anisotropy field（HA） and the magnetization at an applied field of 7 T（M7 T） decrease with the increase of Tm content. However, the thermal stability of both the HAand M7 Tof all the Tm doped compounds is remarkably improved compared with that of the pure SmCo5 compound, leading to the result that both the M7 Tand HAof Sm0.8Tm0.2Co5 .2are higher than those of SmCo5 compound at 473 K, which indicates the good potential of Tm doped compound in the practical applications at elevated temperature.展开更多
基金State Key Development Program of Basic Research of China(2010CB934600)The Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality
基金financially supported by the National Natural Science Foundation of China(Nos.51331003 and 51371002)the International S&T Cooperation Program of China(No.2015DFG52020)
文摘In this work, the effects of Pr content on the structure and intrinsic magnetic properties of Sml-xPrxCO5 （x = 0-0.6） compounds prepared by induction melting were systematically investigated by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and magnetic measurements. Microstructural observation and chemical composition analysis show that Sml xPrxCos compounds are composed of （Sin, Pr）Co （1：5） phase and （Sm, Pr）-rich grain boundary phase. XRD results show that all the Sml-xPrxCO5 compounds have a （Sm, Pr）lCo main phase with the hexagonal CaCus-type crystal structure and the （Sm, Pr）2 Co7 impurity phase. In addition, the detailed research shows that the lattice constants （a, c） and unit volume （V） are all enlarged with the increases in Pr con- tent. According to the magnetic measurements, as the Pr content increases to larger than 0.4, both the Curie tem- perature （Tc） and the anisotropy field （HA） of all the Pr- doped compounds decrease rapidly. Meanwhile, the mag- netization of Sml_xPr.Co5 compounds at applied field of 14 T （MI4 T） are observably improved with Pr doping content of x 〉 0.3. Among them, Smo.6Pro.4Co5 compound exhibits slightly lower HA and Tc, but much higher M14 T than those of the binary SmCos, indicating that doping of proper Pr content into SmCo5 compound can optimize the intrinsic magnetic properties. As a result, the optimal intrinsic magnetic properties of HA = 29.11 T,Tc = 989 K, and M14 T = 102.31 mA.m2.g-1 are obtained in Smo.6Pro.4C05 compound.
基金financially supported by the State Key Development Program of Basic Research of China (No. 2010CB934600)State Key Laboratory of Advanced Metals and Materials (No. 2011-ZD02)the Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality (No. 009000543113507)
文摘Structure, magnetic properties, and thermal stability of ternary Sm1-xTmxCo5 compounds were studied via X-ray diffraction（XRD）, thermal magnetic analysis（TMA）, and magnetic measurements. XRD results show that all the compounds have a main phase of hexagonal CaCu5-type crystal structure with small amount of impurity phases; increasing Tm content is associated with contraction of the hexagonal unit cell in the direction of the c axis and expansion of the a and b parameters. TMA results indicate that the Curie temperature（TC） of Sm1-xTmxCo5 compounds gets higher with the increase in Tm content.Magnetic measurements show that both the magnetic anisotropy field（HA） and the magnetization at an applied field of 7 T（M7 T） decrease with the increase of Tm content. However, the thermal stability of both the HAand M7 Tof all the Tm doped compounds is remarkably improved compared with that of the pure SmCo5 compound, leading to the result that both the M7 Tand HAof Sm0.8Tm0.2Co5 .2are higher than those of SmCo5 compound at 473 K, which indicates the good potential of Tm doped compound in the practical applications at elevated temperature.
