The microstructure, hardness, and tensile properties of a mechanically alloyed Al–0.35Li–1Mg–0.25C (wt.%)+7.5vol.%TiO 2 material are reported, both as-extruded, and after heat treatments at 500–655 °C for times up to 750 h. Both X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed presence, as-extruded, of Al 3Ti, cubic TiO (C–TiO), and monoclinic TiO (M–TiO) and, in addition, Al 4C 3, MgO, and TiO 2 (brookite, anatase, and rutile) were identified by TEM. The Al 3Ti dispersoids (displaying typically one of two orientation relationships with the α-Al matrix) were essentially spherical, as-extruded, and generally of size 90–150 nm, becoming more elongated and faceted at 655 °C, at which temperature the particle volume increased by a factor of 2.3 between 24 and 168 h exposure. Hardness increased by ∼4, 3, 10 and 23% in 504 h at 500 °C, and 24 h at 550, 600 and 655 °C, respectively, attributable mainly to further reduction of C–TiO and M–TiO to form additional Al 3Ti. Al 2O 3 (mainly the α-variant) was an additional reaction product detected by XRD after 24 h at 655 °C. The starting grain size (0.49±0.18 μm) was unaffected by heat treatment for 24 h at 500 or 550 °C, and increased by only ∼20% during 168 h at 655 °C. Compared with 24 h at 655 °C, the hardness reduced by ∼4 and 78% after 168 and 750 h at this temperature, respectively. While heat treatment for 48 h at 500 °C had little effect on tensile properties, 48 h at 550 °C increased the room temperature yield strength and ultimate tensile strength by ∼7 and 13%, while the elongation to fracture was almost halved compared with the as-extruded condition. Fracture surfaces after room temperature testing, as-extruded, or following heat treatment for 48 h at 550 °C, were ductile, while cleavage fracture resulted from tests at 300 °C, following heat treatment for 48 h at 500 °C.