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In this work, we have proposed a general 3D analytical model for giant magnetostrictive composites based on the Mori-Tanaka theory. Taking into consideration both the interface effect and thermal residual stress (TRS) in the curing process, we have studied the relationship between the effective magnetostriction of giant magnetostrictive composites and different magnetic fields, and investigated the influence of TRS, inclusion shape, and direction of the magnetic field on the effective magnetostriction. The results show that TRS has significant influence on the effective magnetostrictive normal strains but little effect on the effective magnetostrictive shear strains. Both the magnetic field direction and the inclusion shape significantly affect the effective magnetostriction. Moreover, the Wiedemann effect is expected to occur on the giant magnetostrictive composites according to our theoretical calculations. [ABSTRACT FROM AUTHOR]

• A tunable MREs metasurface is proposed to steer the incident flexural waves arbitrarily. • The phase shift in a full 2π span can be achieved by adjusting the modulus of MREs manipulated by the applied magnetic field. • Based on the GSL, MRE metasurfaces with different refraction angles, focal spots and self-bending beam paths are designed. • The focusing effect of the tunable MREs metasurface is verified experimentally. Metasurfaces have remarkable power for steering flexural waves, and most of the existing studies for phase modulation of the metasurface concentrate on changing the geometrical parameters of the structure. However, when the external conditions change, these parameters cannot be adjusted in real-time, which is not convenient for engineering applications. Therefore, in this paper, a tunable magnetorheological elastomers (MREs) metasurface composed of MREs and three-dimensional (3D) printing material polylactic acid (PLA) is proposed to steer the propagation of incident flexural waves arbitrarily. The phase shift in a full 2π span can be achieved by manipulating the applied magnetic field to tune the modulus of the MREs. Then, based on the Generalized Snell's Law, MREs metasurfaces with different refraction angles are designed by adjusting the applied magnetic field, including positive refraction and negative refraction. In addition, wave focusing and self-bending beam effects are also investigated. Different focal spots and self-bending beam paths can be realized by adjusting the applied magnetic field. Finally, a sample of the tunable MREs metasurface is fabricated by 3D printing technology composed of host plate and MREs units to demonstrate the focusing effect experimentally. The results show that the designed tunable MREs metasurface only requires a small magnetic field to achieve deflecting of the flexural waves (the maximum magnetic field is 66.93 mT), which is easy to implement in practical engineering. The simulated and experimental results of the elastic wave focusing effect are in good agreement. The proposed metasurface provides a guiding design for elastic wave modulation. [Display omitted] [ABSTRACT FROM AUTHOR]

• Present a simulation of Rutherford cable's mechanical behaviors in coil-end winding. • Investigate the instability behaviors of the Rutherford cable in coil-end winding. • Consider the effect of cabling angle, friction, winding radius, and orientation. • Give suggestions for better mechanical stability of the wound cable. The High Luminosity upgrade of the LHC and the Hadron Future Collider study framework propose a new requirement of developing 16 T dipoles. Nb 3 Sn Rutherford cable is used to fabricate the superconducting magnets to achieve the goal. During the coil winding process, Rutherford cable's mechanical instabilities often occur at the coil ends, reducing the coil's performance and increasing the difficulty of the winding. In this study, a 1-axis bending model and a 2-axes bending model of the Rutherford cable are built and analyzed to better understand the mechanical behavior during the coil end winding process. The instabilities, such as opening, protrusion, and pop-out, are investigated. Several parameters' influence is considered in the analysis, such as the cable strands' twisting angle, the coil winding radius and orientation, and the friction. [ABSTRACT FROM AUTHOR]