电磁胀形磁场力的有限元分析

研究电磁胀形过程中工件受到的磁压力沿长度方向和厚度方向的分布是工件变形分析的基础。采用有限元方法对电磁胀形过程中作用工件上的磁场力进行了数值模拟。在磁场特性理论分析的基础上确立了模型的边界条件，得到了磁场力沿工件长度和厚度方向的分布规律。模拟结果与测量值基本吻和。     

化学沉积法制备的Ni(P)、Ni(B)纳米薄膜的结构与磁性

用化学沉积法制备了系列Ni(P),Ni(B)合金薄膜样品，用X射线衍射结构分析方法证明样品由尺寸为纳米量级的颗粒组成，样品在磁性上表现出超顺磁性，对热磁处理前后的磁学参数进行了比较研究。     

Superconductivity and magnetism in niobium doped YBa2Cu3O7 Related high Tc ceramics

Magnetic characterization has been performed on the members of the cuprateniobate RBa₂Cu₂NbO₈ (R = Pr, Nd, and La) series and R_1.5Ce_0.5Sr₂Cu₂NbO₁₀ (R = Pr, Eu, Nd, and Sm) series. The PrBCNO samples show a signature in the magnetization of a magnetic ordering at 12K. The PrCSCNO sample is nonsuperconducting and shows two distinct orderings at 17K and 53K. No such magnetic phase transition is observed down to 2K in the Nd and La based RBCNO materials or the Nd, Sm, and Eu based RCSCNO materials. Measurements of the lower critical field curve, dc irreversibility line, and critical curent densities are reported for each of the superconducting NdCSCNO, SmCSCNO, and EuCSCNO compounds.     

Effects of a Nd—Fe—B magnetic filler on the crystallization of poly(phenylene sulfide)

The crystallization of poly(phenylene sulfide) (PPS) in a polymer–magnetic Nd—Fe—B powder suspension was studied. Isothermal crystallization behavior was analyzed by way of differential scanning calorimetry, and the kinetics were described via the Avrami equation. The Avrami parameters and the crystallization times were strongly affected by both the particle size and the presence of a coupling agent coated on the filler particles. The small Nd—Fe—B particles exhibited long induction and half‐times, whereas the large particles tended to have short crystallization times. Particles ranging from 38 to 150 μ appeared to have similar crystallization times and to have no significant change in the value of Avrami index with melt crystallization temperature. As a result of these analyses, the dynamic mechanical properties were determined to correlate the fundamental polymer crystallization characteristics and the physical properties of the PPS binder. The enhancement of the wetting of the filler to the binder was promoted through the coupling agent, as confirmed by dynamic mechanical testing performed on the samples. The storage modulus typically decreased because of the presence of the uncoated small particles. Conversely, the loss modulus was enhanced because of the presence of the coated small particles in the PPS binder. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1091–1102, 2002     

精密角位移传感器及其可靠性研究

从理论上探讨了磁阻率效应，叙述了精密角位移传感器的工作原理及结构设计。传感器的分辨率已达０．０１°，通过可靠性寿命试验，传感器的失效率λ（ｔ）＜１×１０－７／ｈ。     

Numerical solution of the kinematic dynamo problem for Beltrami flows in a sphere

The article discusses computational aspects of the kinematic problem of magnetic field generation by a Beltrami flow in a sphere. Galerkin's method is applied with a functional basis consisting of Laplace operator eigenfunctions. Dominant eigenvalues of the magnetic induction operator and associated magnetic eigenmodes are obtained numerically for a certain Beltrami flow for magnetic Reynolds numbers up to 100. The eigenvalue problem is solved by a highly optimized iterative procedure, which is quite general and can be applied to numerical treatment of arbitrary linear stability problems.     

Power Dissipation in Spintronic Devices Out of Thermodynamic Equilibrium

Quantum limits of power dissipation in spintronic computing are estimated. A computing element composed of a single electron in a quantum dot is considered. Dynamics of its spin due to external magnetic field and interaction with adjacent dots are described via the Bloch equations. Spin relaxation due to magnetic noise from various sources is described as coupling to a reservoir. Resulting dissipation of energy is calculated and is shown to be much less than the thermal limit, ∼kT per bit, if the rate of spin relaxation is much slower than the switching rate. Clues on how to engineer an energy efficient spintronic device are provided.     

点探头涡流无损检测中磁介质作用机理研究

结合实际涡流无损检测应用中的含磁介质点探头的特点，分析了探头中磁介质引入的各种附加效应及其对缺陷阻抗的影响。通过引入等效电流的概念，讨论了磁介质对涡流场的作用，建立含磁介质点探头涡流无损检测模型，并给出含磁介质探头周围的电磁场方程，求得均匀半无限导体系统的磁矢量势分布和导体中涡流、电场强度分布。通过实例，计算了非铁磁性导体中无缺陷时探头信号与提离高度的关系、存在缺陷时探头阻抗变化的特点。理论计算与实验结果基本吻合。     

同步电机转子的检修探讨

同步电动机转子时常由于磁极松动,导致电机振动现象严重.本文以烧结厂1#抽烟机转子检修为例对同步电机的转子检修进行探讨,很好的解决了这个问题.同时为同步电机转子检修提供了一整套检修方法.