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Tianli Zhang

Bio: Tianli Zhang is an academic researcher. The author has contributed to research in topics: Magnet & Coercivity. The author has an hindex of 4, co-authored 6 publications receiving 147 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, a giant magnetostrictive actuator with home-made TbDyFe rods is used for active vibration control in single-degree-of-freedom (DOF) and six-DOF platforms in a flexible space structure.
Abstract: Giant magnetostrictive actuators are designed and fabricated with home-made TbDyFe magnetostrictive rods. The corresponding static and dynamic characteristics are tested. The total output displacement can be obtained up to 100 µm and the output force up to 1500 N. The dynamic responses of input and output are accordant and have a small hysteresis. Experiments on active vibration control are implemented in single-degree-of-freedom (DOF) and six-DOF platforms in a flexible space structure. The excellent damping effect, up to 30 dB, proves the good performance of the actuators, the feasibility of the control algorithms, and the reasonable design of the six-DOF platform.

111 citations

Journal ArticleDOI
TL;DR: In this article, the authors investigated the effect of giant magnetostrictive alloy (GMA) actuators on the performance of an active vibration control system using GMA actuators and showed that there is a better dynamic output only at suitable prestress and magnetic bias values.
Abstract: Giant magnetostrictive alloy (GMA) actuators are tending to replace piezoelectric actuators in many applications owing to their giant magnetostrain and fast response. In an active vibration control system using GMA actuators, the investigation of dynamic magnetostrain can supply the basis for the optimization of actuator designs and control algorithms. Experiments have been carried out under varied operating conditions. The results show that there is a better dynamic output only at suitable prestress and magnetic bias values. For a fixed frequency, the output is basically proportional to the input amplitude but the inclination is slightly different for each input frequency. The natural frequency of the actuator is around 5 Hz and the output displacement decreases with frequency increase after 10 Hz. The dynamic magnetostrain at the natural frequency can be larger than the quasi-static value by up to 40%.

22 citations

Journal ArticleDOI
TL;DR: In this paper, a technique for improving the homogeneity of the magnetic field of tube-like permanent magnets designed for magnetostrictive devices is discussed, which is achieved by gradually changing shape or remanence of combined short rings.
Abstract: This paper discusses a technique for improving the homogeneity of the magnetic field of tube-like permanent magnets designed for magnetostrictive devices. The high homogeneity of the magnetic field along the tube is achieved by gradually changing shape or remanence of combined short rings. The analysis of the field in the magnet is performed using the magnetic charge principle and axial magnetic field equations are deduced. An example of design of a longitudinal uniform field for a magnetostrictive rod with large length to diameter ratio is presented.

20 citations

Patent
06 Aug 2008
TL;DR: In this paper, a 1:7 type nanocrystal permanent magnetic material with a TbCu7 structure is presented, where the atom number of X is 5.5 to 8.5 and atom number Y is 0.1 to 1.5; a third element M is nickel, molybdenum, titanium, carbon, boron, wolfram, tantalum, or platinum.
Abstract: The invention discloses a SmCo 1:7 type nanocrystal permanent magnetic material provided with a TbCu7 structure, wherein, the expression of the nanocrystal permanent magnetic material is SmCoXMY; the atom number of X is 5.5 to 8.5; the atom number of Y is 0.1 to 1.5; a third element M is nickel, molybdenum, titanium, carbon, boron, wolfram, tantalum, gallium or platinum. After high-temperature arc or high-frequency induction smelting, coarse crushing, high-energy ball milling and amorphous heat treatment crystallization of the nanocrystal permanent magnetic material, the SmCo 1:7 type nanocrystal permanent magnetic material provided with the TbCu7 structure is prepared. The room temperature intrinsic coercive force of the SmCoXMY nanocrystal permanent magnetic material is 950 to 1900 kiloamperes per meter; the saturation magnetization is 0.58 to 1.0T; the Curie temperature is 780 to 900 DEG C.

6 citations

Patent
26 Jul 2006
TL;DR: In this article, anamorphism magnetism was distributed evenly along magnetic field axis direction, which comprises upper sphere section, center section, and down section with hollow center, wherein, the upper and down sections are located on the top and down position of the center section with different electrode binding.
Abstract: This invention relates to one anamorphism magnetism distributed evenly along magnetic field axis direction, which comprises upper sphere section, center section and down section with hollow center, wherein, the upper and down sections are located on the top and down position of the center section with different electrode binding; the upper and down sections have same inner and outer radium's lengths with same inner radium; the magnetic field distribution of each section as Hu?z,R2)u¢-Br/2a–0[[(z. u½l)/(zu½l)2R22-(z-l)/(z-l)2u½R22]. The invention is made by the requirements of the intelligent materials needed magnetic size to change magnetic sphere outer radium or remaining field size.

2 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors provide an overview of advances and presents the prospects for integrating switchable molecular materials as active elements into actuator devices, with particular emphasis on micro-and nanoscale systems.

191 citations

Journal ArticleDOI
TL;DR: There is a broad range of successful utilization of Laves phases in functional applications including hydrogen storage material (Hydraloy), as magneto-mechanical sensors and actuators (Terfenol), or for wear and corrosion-resistant coatings in corrosive atmospheres and at high temperatures (Tribaloy).
Abstract: Laves phases with their comparably simple crystal structure are very common intermetallic phases and can be formed from element combinations all over the periodic table resulting in a huge number of known examples. Even though this type of phases is known for almost 100 years, and although a lot of information on stability, structure, and properties has accumulated especially during the last about 20 years, systematic evaluation and rationalization of this information in particular as a function of the involved elements is often lacking. It is one of the two main goals of this review to summarize the knowledge for some selected respective topics with a certain focus on non-stoichiometric, i.e., non-ideal Laves phases. The second, central goal of the review is to give a systematic overview about the role of Laves phases in all kinds of materials for functional and structural applications. There is a surprisingly broad range of successful utilization of Laves phases in functional applications comprising Laves phases as hydrogen storage material (Hydraloy), as magneto-mechanical sensors and actuators (Terfenol), or for wear- and corrosion-resistant coatings in corrosive atmospheres and at high temperatures (Tribaloy), to name but a few. Regarding structural applications, there is a renewed interest in using Laves phases for creep-strengthening of high-temperature steels and new respective alloy design concepts were developed and successfully tested. Apart from steels, Laves phases also occur in various other kinds of structural materials sometimes effectively improving properties, but often also acting in a detrimental way.

109 citations

Journal ArticleDOI
TL;DR: In this article, a linear model of magnetostrictive actuators that is valid in a range of frequencies below 2 kHz is presented. And the model is validated through experimental tests carried out on two different magnetic actuators.
Abstract: One of the most frequent applications of magnetostrictive actuator technology is the active structural vibration control (AVC). Magnetostrictive actuators (MAs) can deliver high-output forces and can be driven at high frequencies. These characteristics make them suitable for a variety of vibration control applications. The use of this technology, however, requires an accurate knowledge of the dynamics of such actuators. Several models are available in the literature. However, their use in control applications, characterized by high dynamics, is often limited by nonlinearities and complexity of the model. To overcome this difficulty, the paper introduces a linear model of magnetostrictive actuators that is valid in a range of frequencies below 2 kHz. The assumptions supporting the linearity of the system are discussed and the theoretical model is presented. Finally the model is validated through experimental tests carried out on two different magnetostrictive actuators.

104 citations

Journal ArticleDOI
TL;DR: An inverse compensation approach for Preisach model using the inverse multiplicative structure is developed and results for a magnetostrictive actuator demonstrate the effectiveness of the proposed approach.
Abstract: Compensation of hysteresis nonlinearities in smart material based actuators presents a challenging task for their applications. Many approaches have been proposed in the literature, including the inverse multiplicative scheme. The advantage for such a scheme is to avoid direct model inversions. However, the approach is mainly developed for the Bouc-Wen model. Focusing on the Preisach model which is utilized to describe magnetostrictive actuators, in this paper an inverse compensation approach for Preisach model using the inverse multiplicative structure is developed. Since the input signal is implicitly involved in the Preisach model, it imposes a great challenge to construct the inverse function of the model. To obtain an explicit expression of the input signal from its implicit form so that the inverse multiplicative technique can be applied, the Preisach model is decomposed into a non-memory part and memory part. Using this separation, it only requires to solve the inverse of the non-memory part to obtain an explicit expression of the input signal, thus avoiding constructing the inverse for entire complex dual integral formulation of the Preisach model. Experimental results for a magnetostrictive actuator demonstrate the effectiveness of the proposed approach.

103 citations

Journal ArticleDOI
TL;DR: In this paper, a linear magnetostrictive actuator (MSA) using Terfenol-D as a control device was designed and fabricated, and a series of experimental and numerical tests were performed.

93 citations