A smart magnetorheological elastomer (MRE)-based triboelectric nanogenerator (TENG) with tunable electric–mechanical performance has been developed by assembling MREs, Cu foil and metal wires. The MRE polymer, composed of carbonyl iron and a shear stiffening elastomer matrix, shows a high response to a magnetic field, and the MR effect is 114.68% with a maximum storage modulus of 0.77 MPa. The TENG presents a positive triboelectric performance (PTP) with an increase in the loading pressure. It generates a maximum power of 55.07 μW with a voltage of 20.99 V and lights up 39 LEDs, which proves the high mechanical energy-harvesting properties. More interestingly, the TENG shows a negative triboelectric performance (NTP) under the excitation of a magnetic field owing to the high MR effect and saturated magnetization value of 147.51 emu g⁻¹. Therefore, the overall triboelectric properties of the TENG can be precisely manipulated by alternating the external multi-fields. In addition, the intelligent TENG, with a fast response and high flexibility, functions as a portable self-powered sensor to monitor human motion, distinguish various contact materials, and perceive external magnetic fields. To this end, this work opens up a new avenue to develop a smart TENG device with tunable rheological and triboelectric properties and the self-powered wearable sensor could detect complex multi-field circumstances, which proves it has promising applications in smart energy generation systems and wearable multi-sensing electronics.

This study is an experimental investigation on the tensile responses of Ti–5Al–2.5Sn alloy over a wide range of strain rates. Uniaxial tension tests within the rate range of 10⁻³–10¹ s⁻¹ are performed using a hydraulic driven MTS810 machine and a moderate strain-rate testing system. The high-rate uniaxial tension and tension recovery tests are conducted using a split-Hopkinson tension bar to obtain the adiabatic and isothermal stress–strain responses of the alloy under dynamic loading conditions. The experimental results show that the value of the initial yield stress increases with the increasing strain rate, while the strain rate sensitivity is greater at high strain rates. The isothermal strain-hardening behavior changes little with the strain rate, and the adiabatic temperature rise is the main reason for the reduction of the strain-hardening rate during high strain-rate tension. The electron backscatter diffraction (EBSD) analysis of the post-deformed samples indicates that there are deformation twins under quasi-static and high-rate tensile loadings. Scanning electron microscope (SEM) micrographs of the fracture surfaces of the post-deformed samples show dimple-like features. The Zerilli–Armstrong model is modified to incorporate the thermal-softening effect of the adiabatic temperature rise at high strain rates and describe the tension responses of Ti–5Al–2.5Sn alloy over strain rates from quasi-static to 1050 s⁻¹.