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This paper investigates the possibility of in-situ formation of TiB2ceramic particulates via the process of mechanical alloying of elemental Ti and B powders in a system diluted with Al. Elemental Al powder was mechanically milled together with Ti and B powders in a high energy planetary ball mill. 30 stainless steel balls with diameter of 15 mm were employed. The ball to powder weight ratio was 20:1. X-ray spectra revealed the evolution of structural changes of the alloyed powder particles. No evidence of formation of TiB2 was manifested when the milling duration was shorter than 30 h. A TiB2-like structure could be detected only after 40 hour of milling. Because of broadening and weakening of the X-ray diffraction (XRD) peaks corresponding to Al and TiB2structures as a result of refinement of crystalline size and the presence of large structural distortion, only very weak and vague TiB2XRD peaks could be detected. Clear evidence of formation of TiB2was, however, observed when the mechanically alloyed powder was annealed. Therefore, the results of the present investigation clearly indicate that formation of in-situ TiB2particulates within Al is possible although a longer milling duration is required. Mechanical testing shows that both the 0.2 % yield and the ultimate tensile stresses are increased with MA duration and sintering duration.