Fabrication of Entangled Tough Titanium Wires Materials and Influence on Three-Dimensional Structure and Properties

Pure titanium (Ti) TA1 fibers/wires with 0.08 and 0.15 mm diameters were processed by a novel method that combined press forming, vacuum sintering (≥10−2 Pa), and heat treatment to fabricate entangled Ti wire materials (ETWMs). The ETWMs exhibited a total porosity ranging from 44.2 ± 0.1 to 81.2 ± 0.1% and an open porosity ranging from 43.5 ± 0.1 to 80.9 ± 0.1%. The processing parameters of fiber diameter, formation pressure, sintering temperature, and sintering time were applied to examine porous ETWM morphology, porosity, pore size, and mechanical properties. The importance of primary factors controlling porous structure and porosity in ETWMs were found to be fiber/wire diameter > formation pressure > sintering temperature > sintering time. Furthermore, Ti fiber diameter was shown to directly impact pore size. High formation pressure resulted in a fine, uniform porous structure with low porosity. Sintering at high temperature for long-time periods promoted sintering point formation, resulting in neck coarsening. This effect contributed to the characteristic mechanical properties observed in these ETWMs. If the sintering effect is considered in isolation, ETWMs fabricated with 0.08 mm diameter Ti fibers/wires and sintered at 1300 °C for 90 min achieved smaller, more uniform porous structures that further exhibited improved connections among fibers/wires and excellent mechanical properties.