Effect of mechanical alloying on the microstructural properties of powder particles for oxide dispersion strengthened ferritic steels

The effects of mechanical alloying parameters, including milling rate and milling time, on the microstructural properties of the as-milled powders were investigated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) results showed that the best milling efficiency could be obtained at a milling speed of 380 r·min^-1 while the grain size of the powder decreased remarkably without obvious particle agglomeration. Peak broadening in the XRD patterns occurred due to the decrease in grain size and mean particle size during mechanical alloying. The particle size decreased with increased milling time and after 30 h milling, the particles were nearly spherical shape with a uniform mean size of 13.4μm. SEM-EDS analysis of the particle cross section surface showed that all alloying elements distributed homogeneously.