The mechanical alloying behaviours of Ti+Al powder mixtures (Ti_(50)Al_(50)) and Ti_(25)Al_(75) have been investigated using various ball milling methods: attrition, vibratory, planetary and conventional horizontal milling. The morphological evolution of the powders was strongly dependent upon the milling methods. For Ti_(50)Al_(50) composition, an amorphization took place in the final stage of the milling where cold welded coarse powders were refined to the particle size of less than 30㎛. For Ti_(25)Al_(75) composition, both amorphous and metastable Al₃Ti phases were formed during the mechanical alloying, and the amount of the amorphous phase increased with increasing the milling time. |
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