Using a depth sensing indentation (DSI) technique, the Martens hardness HM, indentation modulus E IT and deformation work W for Al matrix and Al 4 C 3 particles have been measured on mechanically alloyed system Al–Al 4 C 3 . It has been shown that the hardness of Al 4 C 3 particles (10–14 GPa) is 5–7 times higher than the hardness of matrix. Hard particles absorb 2 times more elastic deformation energy than the soft matrix. Indentation modulus E IT , comparable with Young's modulus is 2.5–5 times higher for particles than that for matrix.