Synthesis and characterization of precipitation hardened amorphous matrix composite by mechanical alloying and pulse plasma sintering of Al_(65)Cu_(20)Ti_(15)

摘要

This study reports synthesis of Al_(65)Cu_(20)Ti_(15) amorphous alloy by mechanical alloying and consolidation of the powder mass by pulsed plasma sintering. During sintering, several intermetallic phases precipitate from the amorphous matrix and cause a significant increase in nano-hardness and elastic modulus. Microstructure in as-milled and sintered conditions was characterized by X-ray diffraction, scanning transmission electron microscopy and differential scanning calorimetric. Among various conditions of sintering, the composites pulse plasma, sintered at 500℃, show the high compression strength (1745 MPa) and high indentation fracture toughness (4.96 MPa m~(1/2)); although, the maximum density (3.73 Mg/in~3), nano-hardness (14 GPa) and Young's modulus (208 GPa) in the present alloy have been obtained in the composites pulse plasma sintered at 600C.