The formation of ternary compounds within the Ti–Al–C system was studied by magnetron sputtering for thin-film deposition and first-principles calculations for phase stability. As-deposited films were characterized with X-ray diffraction (XRD) and high-resolution transmission electron microscopy (TEM). The hardness and Young's moduli of the material were studied by nanoindentation. Epitaxial and phase-pure films of M n +1 AX n phases Ti 3 AlC 2 and Ti 2 AlC as well as the perovskite phase Ti 3 AlC were deposited on Al 2 O 3 (00ℓ) wafers kept at temperatures between 800 and 900°C. The only ternary phases observed at low temperatures (300°C) were Ti 3 AlC and cubic (Ti,Al)C, the latter can be described as a metastable solid solution of Al in TiC similar to the more studied (Ti,Al)N system. The difficulties to form MAX phases at low substrate temperatures were attributed of requirement for a sufficient diffusivity to partition the elements corresponding to the relatively complex crystal structures with long c-axes. While MAX-phase synthesis at 800°C is significantly lower than contemporary bulk sintering processes, a reduction of the substrate temperature towards 300°C in the present thin-film deposition experiments resulted in stacking sequence variations and the intergrowth of (Ti,Al)C.