Titanium-nickel shape memory alloy (SMA) has good biomedical application value as an implant. Alloy corrosion will promote the release of toxic nickel ions and cause allergies and poisoning of cells and tissues. With this background, surface modification of TiNi SMAs using TiC-powder-assisted micro-electrical discharge machining (EDM) was proposed. This aims to explore the effect of the electrical discharge machining (EDM) parameters and TiC powder concentration on the machining properties and surface characteristics of the TiNi SMA. It was found that the material removal rate (MRR), surface roughness, and thickness of the recast layer increased with an increase in the discharge energy. TiC powder’s addition had a positive effect on increasing the electro-discharge frequency and MRR, reducing the surface roughness, and the maximum MRR and the minimum surface roughness occurred at a mixed powder concentration of 5 g/L. Moreover, the recast layer had good adhesion and high hardness due to metallurgical bonding. XRD analysis found that the machined surface contains CuO₂, TiO₂, and TiC phases, contributing to an increase in the surface microhardness from 258.5 to 438.7 HV, which could be beneficial for wear resistance in biomedical orthodontic applications.

Metal–semiconductor–metal (MSM) ultraviolet (UV) photodetectors have been widely studied owing to their advantages such as ease of preparation, high responsivity, and low costs. However, due to the high overlap between the light absorption layer and electron channel, the sensitivity of UV photodetectors needs to be improved. In this study, the direct generation of zinc oxide nanowires (ZnO NWs) with short lengths by focused ion beam (FIB) exposure of spin-coated zinc acetate films was observed for the first time. The bottoms of the short ZnO NWs were in contact with each other while the tops were independent of each other, which separated the light absorption layer of the UV photodetector from the electron channel, thereby effectively reducing the dark current of the UV photodetector and improving its sensitivity. A high on/off ratio of 13447 was achieved for the UV photodetector based on the as-prepared short ZnO NWs, and a high responsivity and specific detectivity were obtained, with a value of 25.33 A/W and 3.24×1013 Jones, respectively. To optimize the response characteristics of the UV photodetector, the as-prepared short ZnO NWs were annealed at 350 °C and used as the seed layer to hydrothermally grow ZnO NWs with the bottoms not in contact with each other. This UV photodetector achieved an on/off ratio of 28378, a responsivity of 209.27 A/W, and a specific detectivity of 1.4×1014 Jones. We directly prepared short ZnO NWs using FIB to achieve highly sensitive UV detection for the first time, offering new ideas and approaches for the design and preparation of high-performance UV photodetectors.