Structure evolution of Y2O3 nanoparticle/Fe composite during mechanical milling and annealing

Tong Liu, Hailong Shen, Chenxi Wang, Wusheng Chou
2013 Progress in Natural Science: Materials International  
Fe-25 wt% Y 2 O 3 composite powders have been fabricated by mechanical milling (MM) Fe powders of 100 μm in diameter and Y 2 O 3 nanoparticles in an argon atmosphere for the milling periods of 4, 8, 12, 24, 36, and 48 h, respectively. The features of these powders were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe micro analyzer (EPMA) and transmission electron microscopy (TEM). The experimental results showed that the mean particle size and
more » ... particle size and crystalline size of MM powders decreased with the milling time increasing. All the elements distributed homogenously inside the powders after 48 h of MM. The lattice constant of the matrix α-Fe kept constant with the milling time, and no solid solution took place during MM process. After 8 h of MM, the α-Fe in each powder became nanocrystalline. After 48 h of MM, Y 2 O 3 changes from nanostructure into amorphous structure, and the crystalline size of α-Fe further decreased to 10 nm. The Y 2 O 3 in the powders mechanically milled for 48 h kept the amorphous structure after being annealed at 400 1C, and starts to crystallize when the powders are annealed at 600 1C. The amorphous Y 2 O 3 contains a small amount of Fe, and crystalline FeYO 3 appears at 800 1C.
doi:10.1016/j.pnsc.2013.06.009 fatcat:jys4y25bprbr7in4s2pkj56kt4