STUDYING THE EFFECT OF PRODUCTIVE FACTORS ON SYNTHESIS OF NANOSTRUCTURE TIAL (γ) ALLOY BY MECHANICAL ALLOYING

Abstract In this research, the Planetary mill was used for mechanical alloying (MA) of Ti and Al powder mixture with equal at% (Ti50Al50). The effect of various factors, such as process control agent (PCA), speed of rotation of vial and ball-to-powder weight ratio, on process were studied and the best condition to synthesis the alloy was determined. Study on X-ray diffraction (XRD) patterns showed that at primary hours of milling, the powder mixture transmitted to metastable solid solution phase and with increasing the alloying time, that phase transformed to an amorphous, ultra fine grain and homogenous phase. Changes in grain size, lattice strain and impurity content during alloying and various condition were studied and at last with annealing of the product, the TiAl (γ) phase with high purity and nanostructered form was produced.