The fracture-behaviors of two Ti-Al-Sn-Zr-Mo-Nb-W-Si alloys with different slow-diffusing β stabilizing elements (Mo, W) were investigated through in-situ tensile testing at 650 • C via scanning electron microscopy. These alloys have two phases: the α phase with hcp-structure (a = 0.295 nm, c = 0.468 nm) and the β phase with bcc-structure (a = 0.332 nm). Three-dimensional atom probe (3DAP) results show that Mo and W mainly dissolve in the β phase, and they tend to cluster near the α/β phase boundary. Adding more slow-diffusing β stabilizing elements can improve the ultimate tensile strength and elongation of the alloy at 650 • C. During tensile deformation at 650 • C, microvoids mainly initiate at α/β interfaces. With increases in the contents of Mo and W, the β phase content increases and the average phase size decreases, which together have excellent accommodative deformation capability and will inhibit the microvoids' nucleation along the interface. In addition, the segregation of Mo and W near the α/β interface can reduce the diffusion coefficient of the interface and inhibit the growth of microvoids along the interface, which are both helpful to improve the ultimate tensile strength and plasticity.

This study focused on the effects of Zn and Ni addition on the antibacterial properties and corrosion resistance of copper alloys. The antimicrobial properties of copper and copper alloys were evaluated using Escherichia coli ATCC 8739 bacterial strain by employing the overlay and plate counting methods. X-ray photoelectron spectroscopy (XPS) was used to analyze the surface composition of the alloy after contact with bacteria. A salt spray method was used to simulate an artificial sweat contact environment to test the discoloration and corrosion resistance of the alloy, and scanning electron microscopy (SEM) was used to analyze the film layer and surface material composition of the corroded samples. The addition of Ni reduced the antibacterial performance of pure copper; however, the antibacterial performance of the alloy remained fast and efficient after the addition of Zn. Moreover, the addition of Zn and Ni significantly improved the corrosion resistance and surface discoloration of copper alloys in artificial sweat environments. This study provided support for the future application of copper alloys as antimicrobial surface-contact materials with safer public and medical environments in the face of diseases spread by large populations. Graphical abstract Supplementary Information The online version contains supplementary material available at 10.1007/s12598-022-02098-8.