IJNM  Vol.2 No.2 , April 2013
Ball Milling and Annealing of Co-50 at% W Powders
ABSTRACT

Broadening and height reduction of X-ray diffraction peaks were observed after cold-pressing of unmilled Co-W powder mixture. It seems the effect of cold pressing has slightly reduced the lattice parameter of W from 3.165 to 3.143?. Consequent annealing of unmilled compacts yielded metastable phases. Upon 10 and 20 h ball milling of Co-W powder, no alloying was obtained. Although milling did not yield significant crystal changes in W and Co ground state structures, its effect is evident during subsequent annealing. An eta phase is obtained for the first time from unmilled-annealed Co-W powder mixture in the absence of interstitial elements like carbon, while the milled counterpart yielded the rhombohedral Co7W6-type phase with composition deviated from stoichiometric value.


Cite this paper
Bolokang, A. , Phasha, M. and Motaung, D. (2013) Ball Milling and Annealing of Co-50 at% W Powders. International Journal of Nonferrous Metallurgy, 2, 41-46. doi: 10.4236/ijnm.2013.22006.
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