To bear more loads for heavy truck pistons, the shape of heavy truck piston pinhole is often designed as noncylinder form. Current methods cannot meet the needs for precision machining on non-cylinder piston pinhole ...To bear more loads for heavy truck pistons, the shape of heavy truck piston pinhole is often designed as noncylinder form. Current methods cannot meet the needs for precision machining on non-cylinder piston pinhole （NCPPH）. A novel mechanism based on giant magnetostrictive materials （GMM） is presented. New models are established for the servo mechanism, GMM, and magnetizing force of the control solenoid to characterize the relationship between the control current of the solenoid and the displacement of the giant magnetostrictive actuator （GMA）. Experiments show that the novel mechanism can meet the needs to perform fine machining on NCPPH effectively.展开更多
Rare earth giant magnetostrictive materials(GMMs)Tb_(1-x)Dy_(x)Fe_(2±δ)(Tb-Dy-Fe)have been successfully employed in many microelectromechanical devices due to their excellent magnetostrictive properties at room ...Rare earth giant magnetostrictive materials(GMMs)Tb_(1-x)Dy_(x)Fe_(2±δ)(Tb-Dy-Fe)have been successfully employed in many microelectromechanical devices due to their excellent magnetostrictive properties at room temperature.However,Tb-Dy-Fe still shows a relatively large coercivity with high hysteresis,which inevitably limits its application range.Herein,micromagnetic simulations are performed to investigate the size effect of precipitated phase(α-Fe)on coercivity in Tb-Dy-Fe.Simulation results demonstrate that the coercivity is reduced from 31.46 to 12.48 mT with increasing the size ofα-Fe from 4 to 50 nm in Tb-Dy-Fe since the precipitated phase ofα-Fe can act as a magnetization reversal nucleus.This decreasing trend of coercivity can be well fitted with an inverse square relationship,which agrees well with the nucleation theory.Our study highlights that the coercivity of Tb-Dy-Fe can be tailored by tuning the size ofα-Fe precipitation.展开更多
A new type of high-frequency micro-pump was designed, in which GMA (Giant Magnetostrictive Actuator) was employed to replace the traditional motor drive, owing to its significant characteristics of fast response, high...A new type of high-frequency micro-pump was designed, in which GMA (Giant Magnetostrictive Actuator) was employed to replace the traditional motor drive, owing to its significant characteristics of fast response, high accuracy, easily miniaturized and so on. Both the mathematic and simulation models of the micro-pump were built.A set of raw data was used for simulation studies.The results show that the micro-pump based on GMA has achieved the features of high-frequency response and high accuracy, theoretically displaying the performance merits of a giant magnetostrictive material (GMM) high-frequency micro-pump.展开更多
Powder metallurgy technique was applied to prepare rare earth giant magnetostrictive materials. This preparation process consists of casted Tb0.30Dy0.70 Fe1.80 alloy, in magnetic atmosphere. which is pulverized by bal...Powder metallurgy technique was applied to prepare rare earth giant magnetostrictive materials. This preparation process consists of casted Tb0.30Dy0.70 Fe1.80 alloy, in magnetic atmosphere. which is pulverized by ball mill, aligned field, compacted and sintered in inertial The experimental results indicate that when the magnetic field is 240 kA ·m^-1, the sample with particle size less than 0. 147 mm being compacted in magnetic field exhibits 1613 × 10^-3 magnetostriction under a compressive pre-stress 8.0 MPa after being sintered at 1200 ℃ for 2 h and annealed at 950 ℃ for 24 h.展开更多
The coupling iteration (CI) of the finite element method(FEM) is used to simulate the magnetic and mechanical characteristics for a GMM actuator. The convergent ability under different prestress and different load typ...The coupling iteration (CI) of the finite element method(FEM) is used to simulate the magnetic and mechanical characteristics for a GMM actuator. The convergent ability under different prestress and different load types is investigated. Then the calculated deformations are compared with the experimental values. The results convince that the CI of FEM is suitable for the simulation of energy coupling and transformation mechanism of the GMM. At last, the output deformation properties are studied under different input currents, showing that there is a good compromise between good linearity and large strain under the prestress 6 MPa.展开更多
Design of a giant magnetostrictive ultrasonic transducer for progressive sheet forming was presented.A dynamic analysis of the theoretically designed ultrasonic vibration system was carried out using the finite elemen...Design of a giant magnetostrictive ultrasonic transducer for progressive sheet forming was presented.A dynamic analysis of the theoretically designed ultrasonic vibration system was carried out using the finite element method(FEM).In addition,simulations were performed to verify the theoretical design.Then,a magnetically conductive material was added between the giant magnetostrictive rod and the permanent magnet.Besides,magnetic field simulations of the transducer were performed.The influence of the material thickness of the magnetically conductive material on uniformity of the induced magnetic field was studied.Furthermore,the impedance analysis and amplitude measurement were performed to compare the performance of transducers with and without the magnetically conductive material.The experimental results show that the magnetic field uniformity is the highest when the magnetically conductive material has a thickness of about 1.6 mm.The output amplitude of the giant magnetostrictive transducer is improved by adding the magnetically conductive material.Moreover,the mechanical quality factor and impedance are reduced,while the transducer operates more stably.展开更多
基金the National High-Technology Research and Development Program of China (Grant No.2006AA03z106)
文摘To bear more loads for heavy truck pistons, the shape of heavy truck piston pinhole is often designed as noncylinder form. Current methods cannot meet the needs for precision machining on non-cylinder piston pinhole （NCPPH）. A novel mechanism based on giant magnetostrictive materials （GMM） is presented. New models are established for the servo mechanism, GMM, and magnetizing force of the control solenoid to characterize the relationship between the control current of the solenoid and the displacement of the giant magnetostrictive actuator （GMA）. Experiments show that the novel mechanism can meet the needs to perform fine machining on NCPPH effectively.
基金financially supported by the National Key R&D Program of China(No.2021YFB3501401)the National Natural Science Foundation of China(No.52001103)+1 种基金Zhejiang Provincial Natural Science Foundation of China(No.LQ21E010001)the Ten Thousand Talents Plan of Zhejiang Province of China(No.2019R52014)。
文摘Rare earth giant magnetostrictive materials(GMMs)Tb_(1-x)Dy_(x)Fe_(2±δ)(Tb-Dy-Fe)have been successfully employed in many microelectromechanical devices due to their excellent magnetostrictive properties at room temperature.However,Tb-Dy-Fe still shows a relatively large coercivity with high hysteresis,which inevitably limits its application range.Herein,micromagnetic simulations are performed to investigate the size effect of precipitated phase(α-Fe)on coercivity in Tb-Dy-Fe.Simulation results demonstrate that the coercivity is reduced from 31.46 to 12.48 mT with increasing the size ofα-Fe from 4 to 50 nm in Tb-Dy-Fe since the precipitated phase ofα-Fe can act as a magnetization reversal nucleus.This decreasing trend of coercivity can be well fitted with an inverse square relationship,which agrees well with the nucleation theory.Our study highlights that the coercivity of Tb-Dy-Fe can be tailored by tuning the size ofα-Fe precipitation.
基金Supported by the National Natural Science Foundation of China(59835160)the National Natural Science Foundation of Anhui Province(070414268x)
文摘A new type of high-frequency micro-pump was designed, in which GMA (Giant Magnetostrictive Actuator) was employed to replace the traditional motor drive, owing to its significant characteristics of fast response, high accuracy, easily miniaturized and so on. Both the mathematic and simulation models of the micro-pump were built.A set of raw data was used for simulation studies.The results show that the micro-pump based on GMA has achieved the features of high-frequency response and high accuracy, theoretically displaying the performance merits of a giant magnetostrictive material (GMM) high-frequency micro-pump.
文摘Powder metallurgy technique was applied to prepare rare earth giant magnetostrictive materials. This preparation process consists of casted Tb0.30Dy0.70 Fe1.80 alloy, in magnetic atmosphere. which is pulverized by ball mill, aligned field, compacted and sintered in inertial The experimental results indicate that when the magnetic field is 240 kA ·m^-1, the sample with particle size less than 0. 147 mm being compacted in magnetic field exhibits 1613 × 10^-3 magnetostriction under a compressive pre-stress 8.0 MPa after being sintered at 1200 ℃ for 2 h and annealed at 950 ℃ for 24 h.
基金This project is supported by National Natural Science Foundation of China (No.50077019).
文摘The coupling iteration (CI) of the finite element method(FEM) is used to simulate the magnetic and mechanical characteristics for a GMM actuator. The convergent ability under different prestress and different load types is investigated. Then the calculated deformations are compared with the experimental values. The results convince that the CI of FEM is suitable for the simulation of energy coupling and transformation mechanism of the GMM. At last, the output deformation properties are studied under different input currents, showing that there is a good compromise between good linearity and large strain under the prestress 6 MPa.
基金supported by the National Science Foundation of China(No.51675422)the Shaanxi Province Key Research and Development Plan Project of China(No.2017GY-028)。
文摘Design of a giant magnetostrictive ultrasonic transducer for progressive sheet forming was presented.A dynamic analysis of the theoretically designed ultrasonic vibration system was carried out using the finite element method(FEM).In addition,simulations were performed to verify the theoretical design.Then,a magnetically conductive material was added between the giant magnetostrictive rod and the permanent magnet.Besides,magnetic field simulations of the transducer were performed.The influence of the material thickness of the magnetically conductive material on uniformity of the induced magnetic field was studied.Furthermore,the impedance analysis and amplitude measurement were performed to compare the performance of transducers with and without the magnetically conductive material.The experimental results show that the magnetic field uniformity is the highest when the magnetically conductive material has a thickness of about 1.6 mm.The output amplitude of the giant magnetostrictive transducer is improved by adding the magnetically conductive material.Moreover,the mechanical quality factor and impedance are reduced,while the transducer operates more stably.
