Machinability studies were conducted on three materials: Al6061 (base metal), Al6061 reinforced with 6% TiO₂, and Al6061 reinforced with 6% TiO₂ and 4% graphite (Gr), forming a hybrid metal matrix composite (MMC). Turning experiments were performed on a semi-automatic lathe using an SNMG120408 carbide insert. A Taguchi L27 Orthogonal Array (OA) design was adopted, considering four input parameters—spindle speed, feed rate, depth of cut, and reinforcement percentage—each at three levels. The key output responses evaluated were resultant cutting force, surface roughness, and cutting temperature. Due to the varied influence of machining parameters and reinforcement on each response, identifying the optimal conditions was complex. To address this, Taguchi-Grey Relational Analysis (TGRA) was employed for multi-response optimization. TGRA revealed the optimal parameters for the hybrid MMC as a spindle speed of 800 rpm, feed rate of 0.100 mm/rev, and depth of cut of 1.0 mm. The Signal-to-Noise (S/N) ratio, calculated using the Grey Relational Grade (GRG) with a "higher-the-better" criterion, validated the same optimal settings. Main effect plots supported these findings. ANOVA results showed that feed rate had the most significant effect, followed by spindle speed and depth of cut, with a high R² value indicating strong model reliability. The research showed that feed rate had the highest influence on all responses (54.47%), followed by spindle speed (26.52%). The hybrid composite (Al6061 + 6%TiO₂ + 4%Gr) achieved the lowest surface roughness (0.31 μm), lowest cutting temperature (74 °C), and reduced cutting force (401 N) under optimal conditions.