Mechanical properties of nanocrystalline Mg-Al-Ti alloys

Abstract

Nanocrystalline Mg-Al-Ti metal-metal composite has been synthesized using mechanical alloying (MA). Mg-5wt%Al alloys with Ti varying from 0 to 10.3wt% were synthesized. Different crystalline sizes were obtained by varying the milling durations. The grain size of the as-milled powers was found to decrease with milling time down to the range of about 15-27 nm after 20 hours of milling. Although there was grain growth in the sintering and extrusion processes, the grain size still remained in the nanometer size of about 100 nm. The yield strength, tensile strength and hardness of the extruded specimens after 5 hours of mechanical alloying showed the highest value but they decreased with increase in milling time. The elongation of the extruded specimens was however observed to peak at different milling durations.