Sintering Characteristics of Mechanically Alloyed Al–Ni–Ti Amorphous Powder Consolidated by Pressure-less, Pressure-assisted and Spark Plasma Sintering

Abstract

The present work investigates on the possibility of development of amorphous-based nanocomposites by mechanical alloying followed by consolidation. The elemental powder blend of Al88Ni6Ti6 was subjected to high energy ball milling for 120 h in cemented carbide grinding media at a mill speed of 300 r.p.m. by means of a Fritsch Pulverisette-5 planetary ball mill to obtain a fully amorphous powder. The thermal stability of the mechanically alloyed amorphous powder was studied using a differential scanning calorimeter (STA 409C, NETZSCH, Germany) and also by high temperature X-ray diffraction in vacuum (<1 Pa), and it was found to be stable up to ~500°C. Using the information of thermal stability, an attempt was made to consolidate the powder to produce bulk Al-rich nanocomposites having densities near to the theoretical density.