W-Ni-Fe nanostructure materials synthesized by high energy ball milling①
(State Key Laboratoryfor Powder Metallurgy, Central South University of Technology, Changsha 410083, P.R.China)
Abstract: Investigations were made on the phase evolution and thermal stability of the 90W-7Ni-3Fe(mass fraction,%) milled powders by means of XRD and DTA. The results showed that ball milling produced an ultrafine composite powder consisting of supersolidus solution W(Ni, Fe) and amorphous phase, owing to the fast diffusion rate induced by high density of lattice defects and nanograin boundaries. The amorphous phase results from the extension of the solubility of W inγ-(Ni, Fe) phase which forms during the first 3 h of ball milling.
Key words: heavy metal alloy; mechanical alloying; nanostructure