Surface Characteristics of Nanotube Formed Ti-25Nb-xZr Alloys

The purpose of this study was to investigate surface characteristics of nanotube formed Ti-25Nb-xZr alloys. Ti-25Nb-xZr ternary alloys with 0-15 wt% Zr were manufactured in a vacuum arc-melting furnace. Ingots of the alloys were homogenized in an Ar atmosphere at 1000 degrees C for 12 h, followed by quenching in ice water. Nanotube layers were formed by an electrochemical method in 1 M H3PO4 and 0.8 wt% NaF at 30 V for 1 h. As the Zr content of the Ti-25Nb-xZr Alloys increased, the crystals transformed from a needle-like to equiaxed structure. Two nanotube sizes were obtained on the Ti-25Nb-xZr alloys. As the Zr content was increased, the diameters of the larger tubes decreased, whereas those of the smaller tubes increased. However, increased Zr content in the Ti-25Nb-xZr alloys had little effect on wettability.