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Flexible capacitive sensors have attracted the attention of researchers owing to their simple structure, ease of realization, and wearability. Currently, flexible capacitive sensors mainly have three-dimensional and two-dimensional structures, which are subject to several limitations in their applications. A low-cost, high-efficiency, and continuously processable process was used to wrap nylon DTY (PA) filaments on the surface of silver-coated nylon (SCN) core yarns and impregnate them with waterborne polyurethane (WPU) to obtain SCN/PA/WPU composite yarns, which were then utilized in the design of SCN/PA/WPU for the preparation of one-dimensionally structured flexible capacitive sensors. The morphology and mechanical properties of the SCN core yarn, SCN/PA wrapped yarn, and SCN/PA/WPU composite yarn were characterized. The strain-sensing performance of the sensor was analyzed, and the sensor was used to monitor human physiological activities. The sensor exhibited excellent strain capacitance sensing performance with a strain range of up to 140%. With a gauge factor of 0.66 at 10% tensile strain, it can detect strains as low as 1% and has good repeatability, withstanding more than 3200 tensile-unload cycles at 80% strain. The one-dimensional structure sensor can be used to monitor the large-scale movements of joints and muscles in various parts of the human body and the physiological signals of tiny human movements, such as breathing, coughing, and facial expressions, which have potential applications in the fields of sports monitoring and smart wearable.

Three types of TiB2-HEA ceramic composite were prepared using a non-equimolar ratio CoCrFeNiW0.2high entropy alloy (HEA) as a binder, mechanical alloying (MA), and 1600 °C pressureless sintering (PS) processes. The phase analysis results indicate the presence of TiB2, FCC, and TCP phases in the TiB2-HEA composite. A detailed study was conducted on the microstructure of TiB2-HEA composite. The results indicate that there is a certain solid solubility between TiB2and HEA. The Ti and B elements in TiB2will enter HEA, and the elements in HEA will also enter TiB2. Along with the discovery of many lattice distortion regions in TiB2, a diffraction pattern of P-43m cubic structure was also observed in HEA. HEA has good wettability with TiB2, so it can not only inhibit the grain growth of TiB2, but also improve the performance of TiB2-HEA composite by utilizing the inherent excellent properties of HEA. There are both intergranular and transgranular fractures in the TiB2-HEA composite. The relative density, flexural strength, Vickers hardness, fracture toughness, and electrical resistivity of TiB2-30 wt%HEA are 99.7%, 680 MPa, 18.6 GPa, 6.4 MPa m1/2, and 5.7 × 10−7 Ω m, respectively.