Hard disk drives (HDDs) used for data servers are exposed to various vibrations. These vibrations are mainly caused by the cooling fan that controls the temperature inside the server. The vibration affects the positioning accuracy of magnetic heads that read/write digital data. This is an obstacle to obtaining high data transfer rates. To compensate for […]
Depending on the stator lamination manufacturing processes (e.g., punching, laser cutting, clamping, welding, interlocking, and bonding), the motor’s magnetic performance parameters, such as cogging torque, hysteresis torque, and iron losses, can vary significantly. In sub-fractional horsepower (SFHP) permanent magnet motors, the manufacturing influence is typically even more severe because, due to their small dimensions, practically, […]
Nickel thin films (100 nm) deposited on 128∘Y -cut: LiNbO 3 exhibits a well-defined, uniaxial, magnetic anisotropy after annealing at 325 °C. Simulating the magnetization of these films using a temperature-dependent Stoner–Wohlfarth (SW) model indicates that the films have a very narrow angular distribution of anisotropy axis orientations. Here, we report a direct measurement of the angular distribution of […]
Effective medium theory replaces a given fine-scale heterostructure with a homogeneous one in such a way that the physically measurable quantities, e.g., reaction fields and losses, remain approximately the same. This article presents a peculiar case where the physical nature of the problem and the type of governing mathematical equations change upon homogenization. We consider […]
The spin Hall magnetoresistance (SMR) of Pt/FeCoB bilayers with in-plane magnetocrystalline anisotropy was analysed with respect to a second order effect in the sensing current which acts, through the spin Hall effect in Pt, as a torque on the magnetization of the ferromagnetic layer and changes slightly its configuration. This leads to a small current […]
The Dzyaloshinskii-Moriya interaction (DMI), that is the antisymmetric part of the exchange coupling tensor, favors the perpendicular arrangement of magnetic moment, thus, induces canting in otherwise collinear structures. The DMI is the prerequisite for the emergence of weak ferromagnetism in antiferromagnets, but can stabilize twisted magnetic textures, such as spin spirals, soliton lattices and magnetic […]
In this article, electromagnet layouts are presented, which generate a magnetic field with a magnitude gradient that does not vary significantly in a horizontal plane but decreases monotonically with the vertical height above the magnet. Such a one-direction magnetic field gradient is a specific requirement for magnetic density separation (MDS), a novel recycling technology that […]
This article discusses the optimum layout of coils of a superconducting magnet system for magnetic density separation (MDS). MDS is a novel separation technology that combines a vertical magnetic field gradient with a ferrofluid to separate mixtures of non-magnetic particles based on their mass density. The MDS process can separate more than two types of […]
The multiscale finite element method (MSFEM) is a valuable tool to solve the eddy current problem in laminated materials consisting of many iron sheets, which would be prohibitively expensive to resolve in a finite element mesh. It allows using a coarse mesh that does not resolve each sheet and constructs the local fields using predefined […]
This article shows the effectiveness of combining non-intrusive stochastic techniques with 3-D modeling tools to build adequate surrogate models for the evaluation of human exposure close to a vehicle equipped with a wireless charging pad. A surrogate model is appropriate to deal with uncertainties and variabilities of parameters defining the electromagnetic problem. Numerical results obtained […]