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Journal of iron and steel Research International 2008年第3期15卷 82-86页

作者： WANG Kuang-fei LI Bang-sheng MI Guo-fa GUO Jing-jie FU Heng-zhi School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454100 Henan China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 Heilongjiang China

Solute diffusion controlled solidification model was used to simulate the initial stage cellular to dendrite transition of Ti44Al alloys during directional solidification at different velocities. The simulation results show that during this process, a mixed structure composed of cells and dendrites was observed, where secondary dendrites are absent at facing surface with parallel closely spaced dendrites, which agrees with the previous experimental observation. The dendrite spacings are larger than cellular spacings at a given rate, and the columnar grain spacing sharply increases to a maximum as solidification advance to coexistence zone. In addition, simulation also revealed that decreasing the numbers of the seed causes the trend of unstable dendrite transition to increase. Finally, the main influence factors affecting cell/dendrite transition were analyzed, which could be the change of growth rates resulting in slight fluctuations of liquid composition occurred at growth front. The simulation results are in reasonable agreement with the results of previous theoretical models and experimental observation at low cooling rates.

关键词： Ti44Al alloy cell/dendrite transition directional solidification solute diffusion controlled model cell/ dendrite spacing

Preparation,Structure and Mechanical Properties of Nickel Based Porous Spherical Superalloy

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Journal of iron and steel Research International 2009年第1期16卷 92-96页

作者： MI Guo fa LI Hong-yu LIU Xiang-yu WANG Kuang-fei School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454000 Henan China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 Heilongjiang China

The porous superalloy materials with hollow spherical pores were fabricated by using metal powder sintering process. The scanning electron microscope （SEM） observation was applied to the test samples and it revealed that the pores of the porous material exhibited a uniform distribution and the apertures were of same size in principle. The sintering necks appeared between adjacent particles on metal skeleton after sintering. The mechanical properties of the test samples were analyzed and the result showed that this kind of materials possessed excellent energy absorption capability, and the compression resistance decreased with increasing the porosity and aperture.

关键词： porous superalloy material metal powder sintering hollow spherical pore oriented linear pore

Study on cogging force of permanent magnet linear synchronous motor

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Journal of coal Science & Engineering(China) 2005年第1期11卷 89-92页

作者：上官璇峰袁世鹰励庆孚 School of Electrical Engineering Xi'an Jiaotong University Department of Electrical Engi-neering Henan Polytechnic University Jiaozuo 454000 China Department of Electrical Engi-neering Henan Polytechnic University

Presented the methods to obtain the cogging force of permanent magnet linear synchronous motors(PMLSMs), analyzed the characteristics of the cogging force, and provided a basis for reducing the effect of the cogging force. 2-dimensional finite element method(2D FEM) was used to solve the whole motor when its mover was at dif- ferent position, so that the relation was derived between the cogging force and the mover position. The analysis results show that the cogging force between the two ends of the primary iron-core and the secondary permanent magnets (PMs) is sinusoidal function of the mover position under certain conditions only. Two proposed methods, namely direct and indirect methods, are applied to calculate the cogging force between the primary iron-core teeth and the secondary PMs. The agreement of the two methods is validated.

关键词： PMLSMs cogging force FEM

Enhanced extraction of scandium and inhibiting of iron from acid leaching solution of red mud by D2EHPA and sodium chloride

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Journal of Central South University 2021年第10期28卷 3029-3039页

作者： LIWang LIU Yue ZHU Xiao-bo School of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution control Wuhan University of Science and TechnologyWuhan 430081China collaborative innovation center of coal mine safety of Henan Province Henan Polytechnic UniversityJiaozuo 454000China

D2EHPA(P204),tri-butyl-phosphate(TBP)and sodium chloride(NaCl)were attractive for selective extraction of scandium from acid leaching solution of red *** extraction parameters of P204 concentration(X_(P204)),NaCl concentration(C_(NaCl)),pH value,reaction time,stirring speed and O/A were investigated to extract scandium and separate iron from the acid leaching *** extraction mechanism was analyzed by Fourier transform infrared spectroscopy(FT-IR)and thermodynamic *** single-stage extraction efficiency of scandium,iron andβ(Sc/Fe)were 99.1%,9.4%and 1061.2,respectively,with C_(NaCl) of 75 g/L and XP204 of 0.75 at solution pH value of 1.2 and stirring speed of 200 r/min for 6 min,in which a good separation effect of scandium and iron was *** vibration absorption peak Sc─O was contributed to the extraction of scandium with *** complex[FeCln]^(3−n) existed in the solution with adding NaCl into the acid leaching *** value of n was higher and the valence state of the complex[FeCln]^(3−n) was lower with an increase of chloride concentration,which restricts the extraction efficiency of iron with *** extraction of three stages in the counter-current simulation experiments was carried out according to the McCabe-Thiele *** free energy change(ΔG)of−5.93 kJ/mol,enthalpy change(ΔH)of 23.45 kJ/mol and entropy change(ΔH)of 98.54 J/(mol·K)were obtained in the solvent extraction proces,which indicate that the extraction reaction is easily spontaneous and endothermic and a proper increase of temperature is conducive to the extraction of scandium.

关键词： scandium selective extraction D2EHPA/sodium chloride leaching solution red mud

Analysis of temperature field for a surface-mounted and interior permanent magnet synchronous motor adopting magnetic-thermal coupling method

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CES Transactions on Electrical Machines and Systems 2018年第1期2卷 166-174页

作者： Jikai Si Suzhen Zhao Haichao Feng Yihua Hu Wenping Cao School of Electrical Engineering and Automation Henan Polytechnic UniversityJiaozuoChina Department of Electrical Engineering and Electronics University of LiverpoolLiverpoolUK School of Electronics Electrical Engineering and Computer ScienceQueen’s University BelfastdNorthern IrelandUK

Aiming at obtaining high power density of surface-mounted and interior permanent magnet synchronous motor(SIPMSM),it is important to accurately calculate the temperature field distribution of SIPMSM,and a magnetic-thermal coupling method is *** magnetic-thermal coupling mechanism is *** thermal network model and finite element model are built by this method,*** effects of power frequency on iron losses and temperature fields are analyzed by the magnetic-thermal coupling finite element model under the condition of rated load,and the relationship between the load and temperature field is researched under the condition of the synchronous *** addition,the equivalent thermal network model is used to verify the magnetic-thermal coupling *** the temperatures of various nodes are *** results show that there are advantages in both computational efficiency and accuracy for the proposed coupling method,which can be applied to other permanent magnet motors with complex structures.

关键词： Equivalent thermal network method magnetic-thermal coupling method power frequency iron loss surface-mounted and interior permanent magnet synchronous motor(SIPMSM) temperature field

Hollow Gradient-Structured iron-Anchored Carbon Nanospheres for Enhanced Electromagnetic Wave Absorption

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Nano-Micro Letters 2023年第1期15卷 144-160页

作者： Cao Wu Jing Wang Xiaohang Zhang Lixing Kang Xun Cao Yongyi Zhang Yutao Niu Yingying Yu Huili Fu Zongjie Shen Kunjie Wu Zhenzhong Yong Jingyun Zou Bin Wang Zhou Chen Zhengpeng Yang Qingwen Li Key Laboratory of Multifunctional Nanomaterials and Smart Systems Advanced Materials DivisionSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123JiangsuPeople’s Republic of China School of Science Nanchang Institute of TechnologyNanchang 330099JiangxiPeople’s Republic of China Division of Nanomaterials and Jiangxi Key Lab of Carbonene Materials Jiangxi Institute of NanotechnologyNanchang 330200JiangxiPeople’s Republic of China School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026AnhuiPeople’s Republic of China School of Materials Science and Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou 215009People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211800People’s Republic of China Henan Key Laboratory of Materials On Deep-Earth Engineering School of Materials Science and EngineeringHenan Polytechnic UniversityJiaozuo 454003People’s Republic of China college of Safety Science and Engineering Xi’an University of Science and TechnologyXi’an 710054People’s Republic of China

In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption *** inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal *** a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon *** results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight *** addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave *** excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized *** strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.

关键词： Gradient structures Carbon nanospheres Electromagnetic wave absorption Impedance matching