| Summary: | Reactive powder composites Cu-(0–15%)TiH<sub>2</sub> containing up to 5% native Cu<sub>2</sub>O were manufactured by high energy ball milling and then hot-pressed to produce bulk nanostructured copper–matrix alloys reinforced by Cu<sub>3</sub>Ti<sub>3</sub>O inclusions. Two high-energy ball-milling (HEBM) protocols were employed for the fabrication of Cu-Ti alloys: single-stage and two-stage ball milling, resulting in an order of magnitude refinement of TiH<sub>2</sub> particles in the reactive mixtures. Single-stage HEBM processing led to the partial retention of Ti in the microstructure of hot-pressed specimens as the α-Ti phase and formation of fine-grained (100–200 nm) copper matrix interspersed with 5–20 nm Cu<sub>3</sub>Ti<sub>3</sub>O precipitates, whereas the two-stage HEBM led to the complete conversion of TiH<sub>2</sub> into the Cu<sub>3</sub>Ti<sub>3</sub>O phase during the hot pressing but produced a coarser copper matrix (1–2 μm) with 0.1–0.2 μm wide polycrystalline Cu<sub>3</sub>Ti<sub>3</sub>O layers on the boundaries of Cu grains. The alloy produced using single-stage HEBM was characterized by the highest strength (up to 950 MPa) and electrical conductivity (2.6 × 10<sup>7</sup> Sm/m) as well as the lowest specific wear rate (1.1 × 10<sup>−5</sup> mm<sup>3</sup>/N/m). The tribological performance of the alloy was enhanced by the formation of Cu<sub>3</sub>Ti<sub>3</sub>O microfibers in the wear debris, which reduced the friction coefficient against the Al<sub>2</sub>O<sub>3</sub> counter-body. The potential applications of the developed alloys are briefly discussed.
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