In situ synthesis of NbB2-Al2O3 nanocomposite powder by mechanochemical processing

This research is based on the production of NbB2-Al2O3 nanocomposite powder using mechanochemical processing. For this purpose, a mixture of niobium, aluminium and boron oxide powders was subjected to high-energy ball milling. The structural evaluation of powder particles after different milling times was conducted by the X-ray diffractometry (XRD), scanning electron microscopy, and transmission electron microscopy. The results showed that during ball milling the Nb/Al/B2O3 reacted with a combustion mode producing NbB2-Al2O3 nanocomposite. The XRD analyses exhibited that the NbB2-Al2O3 nanocomposite was formed after 10 h milling time and increasing milling time up to 30 h had no significant effect other than refining the crystallite size. In the final stage of milling, the crystallite sizes of NbB2 and Al2O3 were estimated to be less than 50nm.