Mechanochemically assisted preparation of NbB2 powder

A powder mixture of Nb-B (1:2) was milled using milling media of different sizes in a planetary ball mill, and NbB2 was mechanochemically prepared. When the mixture was milled with 5 mm diameter balls, NbB, started to form in 20 h and the single phase NbB, was obtained in 50 h. The time required for the NbB2 formation and the single phase decreased with the increase in the ball size. The lattice parameters of the NbB2 obtained were a = 0.3112 nm, c = 0.3276 nm. The average particle size of the NbB, powder obtained by milling with the 5 and 9 mm diameter balls for 50 h was approximately 370 nm. (c) 2005 Elsevier Ltd. All rights reserved.