Two types of cupric oxide (Cu2O) nanoarchitectures (nanobelts and nanopetal networks) have been achieved via immersion nanoporous copper (NPC) templates in anhydrous ethanol. NPC templates with different defect densities have been prepared by dealloying amorphous Ti60Cu40 ribbons in a mixture solution of hydrofluoric acid and polyvinylpyrrolidone (PVP) with different ratios of HF/PVP. Both a water molecule reactant acting as OH− reservoir and the ethanol molecule serving as stabilizing or capping reagent for inhibiting the random growth of Cu2Oplayed a role of the formation of 2-dimensional Cu2O nanoarchitectures. Cu2O nanobelts are preferred to form in anhydrous ethanol on the NPC templates from Ti60Cu40 ribbons dealloying in the solution with low HF concentration and small addition of PVP; and Cu2O nanopetals are tended to grow in anhydrous ethanol from the NPC templates from Ti60Cu40 ribbons dealloying in the solution with high HF concentration and large addition of PVP. With increasing the immersion time in anhydrous ethanol, Cu2O nanopetals united together to create porous networks about 300 nm in thickness. The defect sites (i.e., twin boundary) on nanoporous Cu ligaments preferentially served as nucleation sites for Cu2O nanocrystals, and the higher defect density leads to the formation of uniform Cu2O layer. Synergistic effect of initial microstructure of NPC templates and stabilizing agent of ethanol molecule results in different Cu2O nanoarchitectures.

Influence of initial microstructure of Ti-6Al-4V ELI alloys on their compressive creep behavior at ambient temperature was investigated with applying compression stresses from 695 to 1092 MPa The experimental results show that the basketweave alloys have better compressive creep resistances than those duplex ones. The constitutive equations in steady-state compressive creeps of duplex or basketweave structure are calculated to be =2.77×10-15(σ-710)2.1 and =2.36×10-14(σ-740)1.7 by fitting the linear regression creep curves after uniaxial compression tests. The noticeable compressive creep strains occur when the applied compression stresses are higher than the threshold stresses, i.e. 710 MPa for duplex Ti-6Al-4V ELI alloys and 740 MPa for basketweave alloys. Microstructural analysis indicates that the creep deformation of Ti-6Al-4V ELI alloys at ambient temperature is mainly controlled by dislocation slip. The creep behavior of Ti-6Al-4V ELI alloy with duplex microstructure is controlled by dislocation slip, like slip dislocations with a-type Burgers vector sliding on the basal or prismatic planes and a few c+a type dislocation sliding on the pyramidal planes. While creep mechanism for basketweave ones is dislocation glide controlled by c+a type Burgers vector sliding on the pyramidal planes and a-type sliding on the basal or prismatic planes.

In order to evaluate electrochemical stabilities of α, β phases, the micro-electrode techniques was employed to test the micropolarization behavior of α-type pure Ti and β-type Ti15Mo alloys. The comparison between macropolarization and micropolarization curves demonstrates that the α-type pure Ti alloy tends to exhibit the uniform corrosion, on the other hand, the pitting corrosion is the main form for the β-type Ti15Mo alloys. The α grains with different orientations shows similar polarization behavior, but the polarization behavior of those β grains are strongly affected by their crystalline orientations, particularly the worse electrochemical stabilities of β grains with (200)-dominance. The corrosion potential and corrosion current density of α-type pure Ti is lower than β-type Ti15Mo alloys. The α grains have better electrochemical stabilities in comparison to β grains, which indicate that the α+β dual-phase Ti-6Al-4V ELI alloys is highly possible to suffer from the preferential dissolution of β grains in free immersion condition and/or polarized states. Finally, by combining the SEM, EDS and polarization curves of dual-phase Ti-6Al-4V ELI alloys, it is concluded that β phases are corroded prior to α phases.