Two metal matrix com (AA 7o75-2 wtxzro, and AA 7075- 5 wt.% zro2) were produced via powder metallurgy. To achieve a complete dispersion of zro2 particles into AA 7075 matrix, 15 h of mechanical milling are needed for the 5 wtxzro2 composite, in con- trast to 10 h for the 2 wt Zro2 composite. size of Zroz, and 2. Ball milling was used to reduce the average particle two variants of milling media were tested. It was found that milling using only balls gave better results since the average particle size was lower than milling with a mixture of balls and rods. nm was 3. After 80 h of Zro2milling, an average particle size of 110 produce achieved. It was confirmed that further milling time did not average additional reduction of the particle size, because at 140 hthe particle size was 108 nm.