For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fas...For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fast estimation of component content in production field. Feature analysis on images of the solution is conducted,which are captured from Pr/Nd extraction/separation field. H/S components in the HSI color space are selected as model inputs, so as to establish the least squares support vector machine(LSSVM) model for Nd(Pr) content,while the model parameters are determined with the GA algorithm. To improve the adaptability of the model,the adaptive iteration algorithm is used to correct parameters of the LSSVM model, on the basis of model correction strategy and new sample data. Using the field data collected from rare earth extraction production, predictive methods for component content and comparisons are given. The results indicate that the proposed method presents good adaptability and high prediction precision, so it is applicable to the fast detection of element content in the rare earth extraction.展开更多
The phase component, the grain size and the magnetic properties of rapidly quenching Nd 9(FeCoZrAl) 85 B 6 amorphous alloy at different heat treatment were investigated. The heat treatment process influences obv...The phase component, the grain size and the magnetic properties of rapidly quenching Nd 9(FeCoZrAl) 85 B 6 amorphous alloy at different heat treatment were investigated. The heat treatment process influences obviously the crystallizing of Nd 2Fe 14 B and α Fe phase, the grain size and the magnetic properties of the alloy. When the heat treatment temperature is lower, the crystallizing of amorphous phase is not sufficient, the grains grow unhomogeneously, so the grain size of Nd 2Fe 14 B phase is much larger. When the heat treatment temperature is much higher, although the amorphous phase is fully crystallized, the grains grow quickly and its size is much larger, too. When the amorphous alloy is heat treated at a proper temperature at 685 ℃ and 30 min, the amorphous phase is fully crystallized and the growth of Nd 2Fe 14 B grains is not remarkable. Thus the grain size is very small, and the magnetic coupling effect reaches a maximum value between the Nd 2Fe 14 B grains and between the Nd 2Fe 14 B grain and α Fe grain, so the alloy possesses good magnetic properties, and the magnetic properties of epoxy resin bonded magnet from the alloy are B r=655 mT, j H c =639 2 kA·m -1 , b H c =381 6 kA·m -1 , ( BH ) m=65 68 kJ·m -3 .展开更多
Crystallographic alignment and magnetic anisotropy were studied for NdxFe94–xB6 （x=8,9,10,11） ribbons prepared via melt-spinning. Effect of Nd content and wheel speed on the crystal structure and magnetic propertie...Crystallographic alignment and magnetic anisotropy were studied for NdxFe94–xB6 （x=8,9,10,11） ribbons prepared via melt-spinning. Effect of Nd content and wheel speed on the crystal structure and magnetic properties of the ribbons was investigated. Both the free and wheel side of the ribbons could obtain strong c-axis crystal texture of Nd2Fe14B phase perpendicular to the ribbons surface at low wheel speed,but the texture weakened gradually with the increase of the wheel speed. Increase of Nd content led to better formation of crystal texture in the ribbons,indicating that the α-Fe phase might undermine the formation of crystal texture. Magnetic measurement results showed that the magnetic anisotropy of the ribbons exhibited corresponding behavior with the invariance of the c-axis crystal texture of Nd2Fe14B phase in the ribbons,and the coercivity of the ribbons rose with the increase of both Nd content and wheel speed during melt-spun process.展开更多
基金Supported by the National Natural Science Foundation of China(51174091,61364013,61164013)Earlier Research Project of the State Key Development Program for Basic Research of China(2014CB360502)
文摘For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fast estimation of component content in production field. Feature analysis on images of the solution is conducted,which are captured from Pr/Nd extraction/separation field. H/S components in the HSI color space are selected as model inputs, so as to establish the least squares support vector machine(LSSVM) model for Nd(Pr) content,while the model parameters are determined with the GA algorithm. To improve the adaptability of the model,the adaptive iteration algorithm is used to correct parameters of the LSSVM model, on the basis of model correction strategy and new sample data. Using the field data collected from rare earth extraction production, predictive methods for component content and comparisons are given. The results indicate that the proposed method presents good adaptability and high prediction precision, so it is applicable to the fast detection of element content in the rare earth extraction.
文摘The phase component, the grain size and the magnetic properties of rapidly quenching Nd 9(FeCoZrAl) 85 B 6 amorphous alloy at different heat treatment were investigated. The heat treatment process influences obviously the crystallizing of Nd 2Fe 14 B and α Fe phase, the grain size and the magnetic properties of the alloy. When the heat treatment temperature is lower, the crystallizing of amorphous phase is not sufficient, the grains grow unhomogeneously, so the grain size of Nd 2Fe 14 B phase is much larger. When the heat treatment temperature is much higher, although the amorphous phase is fully crystallized, the grains grow quickly and its size is much larger, too. When the amorphous alloy is heat treated at a proper temperature at 685 ℃ and 30 min, the amorphous phase is fully crystallized and the growth of Nd 2Fe 14 B grains is not remarkable. Thus the grain size is very small, and the magnetic coupling effect reaches a maximum value between the Nd 2Fe 14 B grains and between the Nd 2Fe 14 B grain and α Fe grain, so the alloy possesses good magnetic properties, and the magnetic properties of epoxy resin bonded magnet from the alloy are B r=655 mT, j H c =639 2 kA·m -1 , b H c =381 6 kA·m -1 , ( BH ) m=65 68 kJ·m -3 .
基金Project supported by the National Natural Science Foundation of China (50871003, 20971116)the Key Project of the International Coopera-tion and Exchanges of Zhejiang Province (2006C14014)
文摘Crystallographic alignment and magnetic anisotropy were studied for NdxFe94–xB6 （x=8,9,10,11） ribbons prepared via melt-spinning. Effect of Nd content and wheel speed on the crystal structure and magnetic properties of the ribbons was investigated. Both the free and wheel side of the ribbons could obtain strong c-axis crystal texture of Nd2Fe14B phase perpendicular to the ribbons surface at low wheel speed,but the texture weakened gradually with the increase of the wheel speed. Increase of Nd content led to better formation of crystal texture in the ribbons,indicating that the α-Fe phase might undermine the formation of crystal texture. Magnetic measurement results showed that the magnetic anisotropy of the ribbons exhibited corresponding behavior with the invariance of the c-axis crystal texture of Nd2Fe14B phase in the ribbons,and the coercivity of the ribbons rose with the increase of both Nd content and wheel speed during melt-spun process.
