Effect of milling parameters on mechanical alloying of aluminum powders

The solid-state interfacial state of aluminum powders was investigated upon inert gas, ball number and size, milling time, speed, and processing control agent (PCA) under high energy planetary mechanical alloying in sub-micron scale. The study observed significant variations in morphology of the milled powders at different milling parameters due to the fracturing and cold welding mechanisms. The uses of different ball numbers and sizes, and with higher rotating speed have resulted in further agglomeration. However, the adding of methanol as the PCA has provided the effective fracture mechanisms, by modifying the surface properties of the deforming particles to overcome the cold welding, hence reducing the particle sizes and changing the morphological shape to granular structures. The milling parameters have been proposed to also include 100 stainless steel balls with 10 mm in diameter, 200 rpm rotational speed, performed under the argon gas for 30 h to effectively produce finer particles and homogeneity in the particle distribution for future sintering process.