Equivalent Young’s Modulus of the Spiral Accumulating Motor Core Including Many Slits and Embossing Interlockings

The motor core is usually manufactured from magnetic steel sheet with press machine. However, usually most parts of the plate are scalped, and only small percent of the sheet is used for the core. The spiral accumulating core system is suitable for manufacturing the core more ecologically because in this system more than 50% of the magnetic steel sheet can be used. However, since the spiral accumulating core has many slits and embossing interlockings, the equivalent Young\u27s modulus is not known. In this study, therefore, the equivalent Young\u27s modulus of the spiral accumulating core is considered in order to find out a good method to fix the core. Here, the finite element method is applied to analyze the permanent magnet motor core, whose layers and slits are periodically arranged. Then, the effects of slits, layers and embossing interlockings on equivalent Young\u27s modulus are discussed. It is found that around the slits the core layer should be considered to have zero elastic modulus because no tangential stress exists. Finally, a convenient method of calculation based on rule of mixture is newly proposed to estimate the equivalent Young\u27s modulus efficiently.11th International Conference on the mechanical behavior of Materials (ICM11), 5-9 June 2011, Como, Ital

Inhomogeneous distribution of flux pinning strength and its effecton irreversibility line and vortex glass-liquid transition line in Bi-2212 tapes

The irreversibility line and the vortex glass-liquid transition line under a magnetic field parallel to the c-axis are investigated for silver-sheathed and dip-coated Bi-2212 tape wires. It is found that the two characteristic lines for silver-sheathed tape is well explained by the flux creep-flow model assuming the distribution of pinning strength with a single peak. On the other hand, general agreements are obtained for these characteristic lines and the critical current density between experiments and theory only when two peaks are assumed in the distribution of flux pinning strength for the dip-coated tape. The causative structure in the dip-coated tape for the peak at small strength in the distribution is discusse

Critical Diagnosis of Electronic Dimensionality Reduction in Semiconductor Quantum Well Structures

Two-dimensional (2D) systems, such as high-temperature superconductors, surface states of topological insulators, and layered materials, have been intensively studied using vacuum-ultraviolet (VUV) angle-resolved photoemission spectroscopy (ARPES). In semiconductor films (heterostructures), quantum well (QW) states arise due to electron/hole accumulations at the surface (interface). The quantized states due to quantum confinement can be observed by VUV-ARPES, while the periodic intensity modulations along the surface normal (kz) direction of these quantized states are also observable by varying incident photon energy, resembling three-dimensional (3D) band dispersion. We have conducted soft X-ray (SX) ARPES measurements on thick and ultrathin III-V semiconductor InSb(001) films to investigate the electronic dimensionality reduction in semiconductor QWs. In addition to the dissipation of the kz dispersion, the SX-ARPES observations demonstrate the changes of the symmetry and periodicity of the Brillouin zone in the ultrathin film as 2D QW compared with these of the 3D bulk one, indicating the electronic dimensionality reduction of the 3D bulk band dispersion caused by the quantum confinement. The results provide a critical diagnosis using SX-ARPES for the dimensionality reduction in semiconductor QW structures

Simulations of interfacial creep generation for shrink-fitted bimetallic work roll

The bimetallic work rolls are widely used in the roughing stands of hot rolling stand mills. The rolls are classified into two types: one is a single-solid type, and the other is a shrink-fitted construction type consisting of a sleeve and a shaft. Regarding the assembled rolls consisting of a sleeve and a shaft, the interfacial creep phenomenon can be seen between the shaft and the shrink-fitted sleeve. This interfacial creep phenomenon causes the relative displacement on the interface between the sleeve and the shaft. Although to clarify this creep mechanism is important issues, experimental simulation is very difficult to be conducted. In this paper, the interfacial creep phenomenon is realized by using the elastic finite element method (FEM) analysis. It is found that the interface creep can be regarded as the accumulation of the relative circumferential displacement on the interface of the sleeve and the shaft.2018 International Conference on Material Strength and Applied Mechanics (MSAM 2018), 10–13 April 2018, Kitakyushu City, Japa

How to obtain the adhesive strength for double lap joint by using single lap joint

The testing method of adhesive strength of lap joint is prescribed in Japanese Industrial Standard (JIS K6850). However, it has been reported that the strength of double lap joint (DLJ) is about two times larger than the one of single lap joint (SLJ). Therefore, suitable testing method has been required from industries. In this study, the equivalent conditions of strength for SLJ and DLJ are investigated in terms of the intensity of singular stress field (ISSF) appearing at the interface end. First, in order to minimize the bend effect for SLJ, the effect of the specimen geometry on ISSF and deformation angle at the interface corner is considered under the same adhesive geometry and load P. It is found that the minimum ISSF of SLJ can be obtained when the adherend thickness t1 is large enough, and the deformation angle at interface corner is also smallest when adherend thickness t1 is large enough. Therefore, it is necessary to use the specimen with thicker adherend thickness. Then, the equivalent conditions of strength for SLJ and DLJ is investigated by changing adherend thickness. The results show that the strength of the DLJ in JIS (t1=1.5mm) can be obtained by using the SLJ with adherend thickness t1=7mm. When the adherend thickness t1≥25mm, the strength of SLJ is nearly equal to that of DLJ.6th International Conference on Fracture Fatigue and Wear, 26–27 July 2017, Porto, Portuga