An electromagnetic NDE technique for measuring the crack ooening displacement of surface fatigue cracks is described. A ferromagnetic resonance probe utilizing yttrium-iron-garnet was used to induce eddy currents in an aluminum plate. The crack opening disolacement of a semi-elliptical fatigue crack evaluated at the surface was measured optically at several values of bending stress on the speci...

Transmission electron microscopy was performed to investigate the microstructure and precipitates in the annealed Co38Ni33Al29 ferromagnetic shape memory alloy. Apart from the dendritic secondary phase in the austenite matrix, micron-sized (up to 100 lm) fcc-based precipitates with partial c0 L12 ordering and containing none, one or three {111}p parallel twin planes were found. The orientation ...

The theoretical study of magnetic semiconductors using the dynamical coherent potential approximation (dynamical CPA) is briefly reviewed. First, we give the results for ferromagnetic semiconductors (FMSs) such as EuO and EuS by applying the dynamical CPA to the s-f model. Next, applying the dynamical CPA to a simple model for A1−xMnxB-type diluted magnetic semiconductors (DMSs), we show the re...

Magneto-acoustic emission (MAE) from wide ribbons of an amorphous ferromagnetic glass (Metglas 2605SC) and from a steel have been studied. The anisotropy of the ribbon is highlighted by applying the magnetic field along the axis of the plate or in a direction perpendicular to it. Two independent experimental set-ups with piezoelectric and inductive detectors coupled to synchronous amplifiers ha...

In this paper, we present a novel, simple and low-cost micromixer that is based on the manipulation of self-assembled structures by an alternating magnetic field of magnetic microbeads over the section of a microfluidic channel. The principle is demonstrated using a microfluidic chip of polymethylmetacrylate (PMMA) that contains a 200 pm wide Y-shaped microchannel and is integrated with soft fe...

The surface impedance of Nb/CuMn (superconducting/spin-glass) bilayers has been measured at 10 GHz with the parallel plate resonator technique to obtain information about the exotic behavior of the order parameter in superconducting/magnetic proximity systems. The data strongly differs from the superconducting/normal-metal case, showing the magnetic nature of the CuMn layer, which acts as a wea...

The Rowell criteria, commonly used to identify tunneling in magnetic tunnel junctions (MTJ), are scrutinized. While neither the exponential-thickness dependence of the conductivity nor fits of non-linear transport data are found to be reliable tunneling criteria, the temperature-dependent conductivity does remain a solid criterion. Based on experimental studies of the bias and temperature-depen...

We have investigated the magnetic properties of a GaN/Ga1−xMnxN (x = 0.1) digital ferromagnetic heterostructure (DFH) showing ferromagnetic behavior using soft x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD). The Mn L2,3-edge XAS spectra were similar to those of Ga1−xMnxN random alloy thin films, indicating a substitutional doping of high concentration Mn into G...

We investigate the ground state of a uniaxial ferromagnetic plate with perpendicular easy axis and subject to an applied magnetic field normal to the plate. Our interest is the asymptotic behavior of the energy in macroscopically large samples near the saturation field. We establish the scaling of the critical value of the applied field strength below saturation at which the ground state change...

the effect of a distributed patch mass on the natural frequency of vibration of a laminated rectangular plate with simply supported boundaries is investigated. the third order displacement field of a composite laminated rectangular plate is defined using the two variable refined plate theory. equations of motion of the plate are obtained with the help of calculus of variation. parametric study ...