采用放电等离子烧结技术制备了Tb Fe Co/Ti复合梯度磁光靶材。利用扫描电子显微镜和电子能谱对材料的显微组织形貌及化学成分进行了观察和分析。结果表明 ,这种Tb Fe Co/Ti复合梯度靶材具有宏观组织不均匀性和微观组织连续性的特征。各...采用放电等离子烧结技术制备了Tb Fe Co/Ti复合梯度磁光靶材。利用扫描电子显微镜和电子能谱对材料的显微组织形貌及化学成分进行了观察和分析。结果表明 ,这种Tb Fe Co/Ti复合梯度靶材具有宏观组织不均匀性和微观组织连续性的特征。各梯度层之间的原子扩散现象不明显。层间界面结合良好 ,不存在微裂纹 ,从而具有较好的力学性能。展开更多
The Tb-Fe-Cr alloy powders were prepared by the arc melting method and high energy ball milling. The phase structure and the mierostructure of the alloys powders were analyzed by X-ray diffraction （XRD） and scanning...The Tb-Fe-Cr alloy powders were prepared by the arc melting method and high energy ball milling. The phase structure and the mierostructure of the alloys powders were analyzed by X-ray diffraction （XRD） and scanning electron microscopy （SEM）, and then their mi- crowave absorbing properties were analyzed by Vector network analyzer. The results showed that the absorption peak values of Tb9FessCr3 alloy with a material thickness of 2.0 mm were lower than -16.5 dB when ball milling time was from 50 to 60 h, and the wide frequency of reflectivity under -10 dB were all more than 4 GHz. When the ball milling time was 50 h, the alloy powders had better electromagnetic properties. The absorption peak value of alloy reached -25.8 dB, and the wide frequency of reflectivity under -10 dB reached 4.8 GHz. When the ball milling time was more than 70 h, the alloy powders would become thinner, leading to worse electromagnetic properties of the alloy, the absorption peak shifted towards low frequency under the same material thickness. The TbxFe97_xCr3 （.v=7, 9, 11, 13, 15 mol.%） alloy dealt with 60 h ball milling time had better wide-frequency characteristic under 1.8 mm of material thickness. The absorption peak shifted towards higher frequency region from lower frequency region with increased atom percent of Tb in the alloy, and the inflexion point appeared when x=13. At low frequency, the microwave absorbing properties of Tb11Fe86Cr3 alloy was better than those of the others. The absorption peak value of Tb11Fe82Cr3 alloy was -24 dB, and the wide frequency of reflectivity under -10 dB was 4.5 GHz.展开更多
TbFe_2,as a typical magnetostrictive material,is ferrimagnetic.Its magnetostrictive property can be improved by an external magnetic field at a temperature below its Curie temperature.In this paper,the effects of high...TbFe_2,as a typical magnetostrictive material,is ferrimagnetic.Its magnetostrictive property can be improved by an external magnetic field at a temperature below its Curie temperature.In this paper,the effects of high magnetic fields on the preferred orientation,phase composition and magnetostrictive property of Tb-Fe alloys during heat treatment process were investigated.It was found that the magnetostriction performance of the alloy annealed in an 11.5 T magnetic field was improved by 30%contrary to that without magnetic field.Such increase can be attributed to the increase in orientation degree of <113> caused by the high magnetic field during the heat treatment.展开更多
Ternary Tb-Fe-B ribbons were prepared via melt-spun technique under different wheel speeds of 5-25 m/s.Effect of wheel speed on the crystal structure and microstructure of the ribbons was investigated.All the ribbons ...Ternary Tb-Fe-B ribbons were prepared via melt-spun technique under different wheel speeds of 5-25 m/s.Effect of wheel speed on the crystal structure and microstructure of the ribbons was investigated.All the ribbons quenched under different wheel speeds crystallized in single Tb2Fe14B phase with tetragon structure.Different crystallographic alignment evolutions were observed in the free side surface and wheel side surface of the ribbons.On the free-side surface,an in-plane c-axis crystal texture of Tb2Fe14B phase was found in the ribbons quenched at 5 m/s.However,with the increase in the wheel speed,the direction of the c-axis texture turns to perpendicular to the ribbon surface.On the wheel-side surface,a strong c-axis texture perpendicular to the ribbon surface was observed in the ribbons quenched at 5 m/s,and then weakened gradually with the increase in the wheel speed.Further investigation showed that the competition of the two types of temperature gradients during the quench process was responsible for the crystallographic alignment evolution in the ribbons.展开更多
The influence of magnetic interactions to the magnetization dynamics was well experimentally studied in a 3d-4f single-molecule magnet(SMM)[Tb^(Ⅲ)_(2)Fe^(Ⅲ)_(3)(μ5-O)L_(2)(NO_(3))_(4)Cl](1,H_(4)L=N,N,N′,N′-tetrak...The influence of magnetic interactions to the magnetization dynamics was well experimentally studied in a 3d-4f single-molecule magnet(SMM)[Tb^(Ⅲ)_(2)Fe^(Ⅲ)_(3)(μ5-O)L_(2)(NO_(3))_(4)Cl](1,H_(4)L=N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylene diamine)and its diamagneticion-diluted samples.Significant ferromagnetic coupling between Tb^Ⅲand Fe^Ⅲions and SMM behavior of 1 were observable,which proved clearly that the magnetic interaction between 3d-4f spin carriers has also an excessive impact on fine-tuning the magnetization dynamic behaviors of 3d-4f complexes.展开更多
文摘采用放电等离子烧结技术制备了Tb Fe Co/Ti复合梯度磁光靶材。利用扫描电子显微镜和电子能谱对材料的显微组织形貌及化学成分进行了观察和分析。结果表明 ,这种Tb Fe Co/Ti复合梯度靶材具有宏观组织不均匀性和微观组织连续性的特征。各梯度层之间的原子扩散现象不明显。层间界面结合良好 ,不存在微裂纹 ,从而具有较好的力学性能。
基金supported by the National Natural Science Foundation of China (50961005)the Natural Science Foundation of Guangxi (0710908-12-Z, 0991002Z)
文摘The Tb-Fe-Cr alloy powders were prepared by the arc melting method and high energy ball milling. The phase structure and the mierostructure of the alloys powders were analyzed by X-ray diffraction （XRD） and scanning electron microscopy （SEM）, and then their mi- crowave absorbing properties were analyzed by Vector network analyzer. The results showed that the absorption peak values of Tb9FessCr3 alloy with a material thickness of 2.0 mm were lower than -16.5 dB when ball milling time was from 50 to 60 h, and the wide frequency of reflectivity under -10 dB were all more than 4 GHz. When the ball milling time was 50 h, the alloy powders had better electromagnetic properties. The absorption peak value of alloy reached -25.8 dB, and the wide frequency of reflectivity under -10 dB reached 4.8 GHz. When the ball milling time was more than 70 h, the alloy powders would become thinner, leading to worse electromagnetic properties of the alloy, the absorption peak shifted towards low frequency under the same material thickness. The TbxFe97_xCr3 （.v=7, 9, 11, 13, 15 mol.%） alloy dealt with 60 h ball milling time had better wide-frequency characteristic under 1.8 mm of material thickness. The absorption peak shifted towards higher frequency region from lower frequency region with increased atom percent of Tb in the alloy, and the inflexion point appeared when x=13. At low frequency, the microwave absorbing properties of Tb11Fe86Cr3 alloy was better than those of the others. The absorption peak value of Tb11Fe82Cr3 alloy was -24 dB, and the wide frequency of reflectivity under -10 dB was 4.5 GHz.
基金Item Sponsored by the National Natural Science Foundation of China(Grant Nos.51006020and51174056)the Fundamental Research Funds for the Central Universities(Grant Nos.N090109001,N100409008,and N100609001)+1 种基金the National Basic Research Program of China(Grant No.2011CB612206)the Wuhan National High Magnetic Field Center(Grant No.WHMFCK2011006)
文摘TbFe_2,as a typical magnetostrictive material,is ferrimagnetic.Its magnetostrictive property can be improved by an external magnetic field at a temperature below its Curie temperature.In this paper,the effects of high magnetic fields on the preferred orientation,phase composition and magnetostrictive property of Tb-Fe alloys during heat treatment process were investigated.It was found that the magnetostriction performance of the alloy annealed in an 11.5 T magnetic field was improved by 30%contrary to that without magnetic field.Such increase can be attributed to the increase in orientation degree of <113> caused by the high magnetic field during the heat treatment.
基金Project supported by the National Natural Science Foundation of China (50871003)
文摘Ternary Tb-Fe-B ribbons were prepared via melt-spun technique under different wheel speeds of 5-25 m/s.Effect of wheel speed on the crystal structure and microstructure of the ribbons was investigated.All the ribbons quenched under different wheel speeds crystallized in single Tb2Fe14B phase with tetragon structure.Different crystallographic alignment evolutions were observed in the free side surface and wheel side surface of the ribbons.On the free-side surface,an in-plane c-axis crystal texture of Tb2Fe14B phase was found in the ribbons quenched at 5 m/s.However,with the increase in the wheel speed,the direction of the c-axis texture turns to perpendicular to the ribbon surface.On the wheel-side surface,a strong c-axis texture perpendicular to the ribbon surface was observed in the ribbons quenched at 5 m/s,and then weakened gradually with the increase in the wheel speed.Further investigation showed that the competition of the two types of temperature gradients during the quench process was responsible for the crystallographic alignment evolution in the ribbons.
基金the National Natural Science Foundation of China(Nos.21622105,21331003 and 21421001)the Natural Science Foundation of Tianjin(No.18JCJQJC47200)the Ministry of Education of China(No.B12015).
文摘The influence of magnetic interactions to the magnetization dynamics was well experimentally studied in a 3d-4f single-molecule magnet(SMM)[Tb^(Ⅲ)_(2)Fe^(Ⅲ)_(3)(μ5-O)L_(2)(NO_(3))_(4)Cl](1,H_(4)L=N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylene diamine)and its diamagneticion-diluted samples.Significant ferromagnetic coupling between Tb^Ⅲand Fe^Ⅲions and SMM behavior of 1 were observable,which proved clearly that the magnetic interaction between 3d-4f spin carriers has also an excessive impact on fine-tuning the magnetization dynamic behaviors of 3d-4f complexes.
