Nanocrystalline W powders with an average crystallite size of about 50nm were produced by mechanical milling. BCT phase was mechanically induced as a result of BCC lattice deformation (compression) along , upon 10h, 20h and 30h milling corresponding to a magnetic saturation of 1.3, 6.9, and 9.8μTm 3/kg. This BCT phase suggests the tetragonal deformation path to be responsible for the observed anomalous magnetism in W. Following DSC-TG thermal analysis, a magnetic saturation of 68μTm 3/kg was obtained upon annealing the 30h milled W powder at 1200°C. In addition, two BCT phases with c/a=1.313 (a=0.29066, c=0.38170nm) and 0.907 (a=0.32602, c=0.29575nm) were detected.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)