Analysis of WC with increased Ta doping
Artikel i vetenskaplig tidskrift, 2015

WC powder with increased Ta doping has been produced. Tungsten and tantalum metal powders were cocarburized to yield a mixture of cubic and hexagonal carbide. The carburization was made through a two-step carburization process with (W,Ta)(2)C powder as an intermediate product. X-ray diffraction analysis showed that the lattice parameters of the hexagonal phase in the fully carburized powder were larger than those of pure WC indicating the formation of a mixed crystal carbide, (W,Ta)C. The powder with the largest lattice parameters was investigated in detail. A method to produce atom probe tomography specimens of this powder was developed. The largest Ta solubility, expressed as Ta/(Ta + W), was 0.086 which is more than four times higher than what previously has been observed. In addition, it was found with electron backscatter diffraction that the (W,Ta)C grains had a large fraction of Sigma 2 grain boundaries as well as a small fraction of what was suggested as Sigma 4 grain boundaries. (C) 2015 Elsevier Ltd. All rights reserved.





Scanning electron microscopy


Jonathan Weidow

Chalmers, Teknisk fysik, Materialens mikrostruktur

E. Halwax

Technische Universitat Wien

W. D. Schubert

Technische Universitat Wien

International Journal of Refractory Metals & Hard Materials

2213-3917 (eISSN)

Vol. 51 56-60


Metallurgi och metalliska material